GIFT OF XaM** 3 &\JL4&l*l yy^pu^, <&Jyi&jyu FORESTRY PAMPHLETS PENNSYLVANIA VOL. IV Pennsylvania Trees, Bulletin Ho. 11. By J. S, Illick, Department of Forestry, Pennsyl- vania State Forest Academy. 1) P +-P3 Lib. 1 .0 OF ROBERT S- C.ON'KLJN.' Commonwealth of Pennsylvania DEPARTMENT OF FORESTRY DIVISION or BULLETIN NO. 11.— JUNE, 1914. V * FORESTRY rf*/Si * ^^»» ^ ^B ^•^tiEGg Of J| AGRICULTURE tutvfRtiTV orcAurpuwiA PENNSYLVANIA TREES BY J. S. ILLICK, A. B., F. E., Professor of Dendrology and Forest Management, Pennsylvania State Forest Academy. ISSUED BY DIRECTION OF THE COMMISSIONER OF FORESTRY. HARRISBURG, PA.: WM. STANLEY RAY, STATE PRINTER 1914 PENNSYLVANIA DEPARTMENT OF FORESTRY ROBERT S. CONKLIN, Commissioner of Forestry. IRVIN C. WILLIAMS, Deputy Commissioner of Forestry. STATE FORESTRY RESERVATION COMMISSION. ROBERT S. CONKLIN, President. SIMON B. ELLIOTT J. LINN HARRIS FRANK L. HARVEY WM. P. STEVENSON. 301953 (3) (4) LETTER OF TRANSMITTAL Hon. Robert S. Conklin, Commissioner of Forestry. Dear Sir: In compliance with your request I have the honor to transmit herewith the manuscript, plates, and photographs for a bul- letin on "Pennsylvania Trees." It is the hope of the writer that the bulletin may aid in developing a fuller appreciation of the im- portance and value of our trees and forests. Yours respectfully, J.' S. ILLICK. Mont Alto, Pa., June, 1914. (5) (6) PREFACE Trees are among the commonest and most conspicuous objects of nature. The numerous products derived from them are very use- ful, often indispensable. In all ages trees and grasses have been the most important products of the soil. A dense and valuable tree growth covered originally almost the entire area of Pennsylvania. About 278 species of trees and shrubs are native to this State, of which number 125 are trees. The number of native representatives in the present forests is the same as in the original forest. While the number of representatives remains the same, yet one finds a marked difference in the degree of their abundance, and in their age, size, form, density, quality, value, and productivity. The original forest of the State was large, dense, and extremely productive. The present forests are small, open, and very unproductive. Each gener- ation of mankind has seen a smaller, more open, and less productive generation of forests. It is not a prophecy, but the statement of a fact, when we say that the source of our timber supply is becom- ing an acute and vital question. Fast- vanishing forests and ever- rising lumber prices are couriers of this fact. The Federal and some State Governments have already inaugurated policies to offset the present destructive tendency in our forests by starting constructive work. To date no state has made a greater advance in forestry than Pennsylvania. She has, however, just started on this useful mission. The men who are directing her forest policies are endeavoring to lay a substantial foundation upon which a stable superstructure may be reared. In order to accomplish this it is necessary to have the co-operation of the citizens of the State, especially the woodland owners and managers. Forestry needs the support of public senti- ment. No substantial and permanent advance is insured until our citizens understand the fundamentals of forestry and can distin- guish the important timber trees from the inferior weed trees. It is hoped that the sphere of usefulness of this bulletin will not be limited to woodland owners and managers, but will extend to lay- men, students, and botanists. Part I is intended for the layman and the beginner of forestry. A careful perusal of this part will enable one to comprehend Part II more fully. The former comprises abstracts from the author's lec- (7) 8 i * «- - ^ i <-• ^ t • "*V , V ; J^U tures on. Elementary Forestry at the Pennsylvania State Forest Academy .\ : Part II is essentially a manual of Pennsylvania trees. It com- prises a discussion on the identification of trees and a description of families, genera, and species, with accompanying keys. The descrip- tive material and keys are the outgrowth of typewritten outline notes prepared by the author and used for the past six years in con- nection with a course in dendrology given at the Pennsylvania State Forest Academy. Each species is described under about 14 headings. No special originality is claimed for the characteristics given under these headings. It is natural to expect that the descriptive mater- ial should correspond with that found in other texts. The author is glad to acknowledge his indebtedness to the many books of refer- ence which were frequently consulted to verify observations and to make the description clear and complete. The range of the species and the weight per cubic foot of their wood (air dry) have been drawn chiefly from Sargent's "The Silva of North America." The distribution in Pennsylvania was worked out in co-operation with the foresters connected with the Department of Forestry and a few others interested in the distribution of trees. Porter's "Flora of Pennsylvania" aided considerably in determining the distribution. Our present knowledge of the distribution of the different species in the State is by no means complete. 'Special efforts are being put forth to ascertain it more accurately. Future publications will con- tain the results of the present and prospective surveys covering the distribution of our trees. Any additions, suggestions, or corrections will be gladly received. The scientific names found in this bulletin are those used by the Department of Forestry, which follows the usage of the seventh edi- tion of Gray's New Manual of Botany. Shifting of individual plates from their proper systematic position was necessary in a few cases in order to place two companion plates on opposite sides of the same sheet. The photographic illustrations, 103 in number, are all original by the author, except Figs. 57 and 63 supplied by W. Gardiner Conk- lin; Fig. 22 supplied by Guy Carleton Hawkins; Figs. 21 and 35 supplied by B. J. Gutknecht, and Figs. 1, 3, 4, 10, and 12 supplied by the Pennsylvania Department of Forestry. The drawings have been made by Miss Margaretta Washington, of Philadelphia, either from specimens supplied by the author or re- drawn and adapted from Sargent's "The Silva of North America" by special permission of the publisher, Houghton Mifflin Company. In making some of the drawings Schneider's "Dendrologische Winter- studien" and some of the reports of the Missouri Botanical Garden were consulted. 9 Grateful acknowledgment is tendered to Hon. Robert S. Conklin, Commissioner of Forestry, at whose suggestion the bulletin was started and under whose careful and constant direction it was de- veloped. Especial acknowledgment is due to Hon. I. C. Williams, Deputy Commissioner of Forestry, who read the entire manuscript, for his inspiration, many valuable suggestions and criticism. Thanks are due to George H. Wirt, Forest Inspector, and Prof. George A. "Retan for their assistance and valuable suggestions. I take pleasure in expressing my gratification to all others who have in any way assisted in this publication, especially the students of the Pennsylvania State Forest Academy for their co-operation, and the graduates for their assistance in collecting data concerning the distribution of trees in this State. J. S. ILLTCK. (10) CONTENTS PART I. INTRODUCTORY. Page. The North American Forest , 13 Forests of Pennsylvania , 13 The Forests and Forestry , 16 Forestry in Pennsylvania, 17 The Structure of the Forest, 19 The Establishment of the Forest, 21 The Development of the Forest, 23 The Protection of the Forest, 26 The Value of Forests, 28 The Value of Trees , 29 Deciduous and • Evergreen Trees , 30 The Age of Trees , 31 The Form and Structure of Trees , . 32 1 . Form , 32 2. Bark, 34 3 . Twigs , 36 4. Buds, 38 5 . Leaves , 40 6 . Leaf-scars and Bundle-scars , 43 7 . Flowers , 44 8. Fruit, 46 9 . Wood, 49 PART II. MANUAL OF PENNSYLVANIA TREES. Identification of Species , 55 Names of Trees, 55 Explanation of Terms and Headings, 56 How to Identify the Species and Use the Keys, 58 General Key to the Families , 63 Tabulation of Genera and Species , 65 Description of the Families, Genera, and Species, 67 Glossary , 220 Index, 225 (11) (12) fftowrrr FORESTRY Of AGKICUUTURC •FCAUFORNIA PART I. INTRODUCTORY. THE NORTH AMERICAN FOREST. There is good reason to believe that the major part of the habi- table earth was originally wooded. North America is no exception to this. The original forest extended from the Atlantic coast west to about the ninetieth meridan having only a few small openings like meadows and the tops of mountains. It also covered a large portion of the Rocky Mountain region and the Pacific slope. Estimates place the aggregate original area of the forests of North America at about 850,000,000 acres. This original area has been so reduced that not more than 550,000,000 acres remain at the present time and a large portion of this acreage is in a very unproductive condi- tion. The original forest of this country was vast in extent and com- posed of many and valuable species. The richness and variety of our tree growth may be in part attributed to the different climatic zones and variable physiographic features common to this country. So variable is our forest structure that at least five general forest regions may be recognized while often a local area may have its own peculiar forest type. Many of the trees in the original forest attained a great age and enormous size. They yielded a vast amount of valuable products, a source of great wealth, which has been supplying the raw material for one of our most important industries. Nature working through many centuries developed the original forest and gave it to us grat- uitously. Man working through only a few centuries has established a great industry — the lumber industry; but on the other hand he has wastefully exploited our forests and left many of them in an un- productive condition. However, there was no alternative because the economic conditions then prevailing required, in part at least this wasteful procedure. FORESTS OF PENNSYLVANIA. The word Pennsylvania means Penn's woods. It derived its name from its early proprietor and the dense and extensive forest growth (13) 14 which covered the State. The original forest covered almost its en- tire area, which is usually given as 28,594,560 acres. Practically the entire State, with the exception of a few natural meadows and the tops of a few mountains, was covered with trees. The original forest was composed of many and valuable species often occurring in dense stands. The richness of our forest flora is due to its favorable location with reference to climatic and physiographic factors. Penn- sylvania is the meeting ground of many northern and southern spec- ies. In the western part of the State one finds outposts of species common to the Mississippi valley, while in the southeastern part some of the species of the coast region are found. Some of the north- ern species have their southern limits here, or else follow the moun- tains toward the south, while some of the southern species have their northern limits here, usually migrating northward through the val- leys. The forests in the southeastern and the western parts of the State are composed almost entirely of hardwoods, while the central and the northern or mountainous parts are composed of a mixture of hardwoods and conifers. One may find the hardwoods by them- selves and the conifers by themselves, or they may occur in mixture. A few of our native species are very valuable, while others are less valuable and some mere forest weeds. The real value of a species changes with the change of the general economic, particularly market, conditions. Within the last decade market prices of wood have risen so much that they have brought about a more intensive utilization of our forest products. Many species formerly left standing in the forest are now utilized. A moment's reflection upon the present tendency in the utilization of the products of the various trees causes us to comprehend fully the truth of the statement that the despised species of to-day will be prized tomorrow. The richness of the arborescent flora together with the great age and large size which some of the trees attained justifies the statement that Pennsylvania was at one time "one of the best timbered states of the Atlantic Coast." Nature working through many centuries developed in this State a forest which was one of the most valuable of the many heritages with which its citizens have been blessed. If we could see maps showing the structure and distribution of the forests of Pennsylvania in the years 1600 and 1900, we would be astonished by the wonderful change that has taken place in a period that represents only a few generations of trees. Many were the agents which brought about this change, but it was left to man to play the leading role. Man working through a few centuries has removed the forest or abused it through fire and unregulated cutting. The establishment of pio- neer homes, the opening of agricultural and grazing lands, the in- crease of population, the development of industrial enterprises, the Fig. 1. STAND OF PENNSYLVANIA VIRGIN WHITE PINE. The kind of forest our forefathers found. A magnificent heritage. The real value was not appreciated. High Fig. 2. RESULT OF EXTENSIVE FOREST EXPLOITATION. stumps, and u thin scattered growth of inferior trees, is all that remains. J he stumps indicate the density and size of the original stand. Fig. 3. ACRES OF DESOLATION. More than 5,000.000 acres of such barren land are found in Pennsylvania. Much valuable timber was lost through reckless exploitation of the original forest. Fig. 4. ACRES OF SCRUB OAK. Scrub Oak has no timber value. Large areas in our forests contain many weed species which often prevent other valuable trees from establishing themselves. 15 destructive work of lumbermen, and the advent of forestry present a picture of change and progress, which enables us in part to com- prehend the important role that man played in transforming the original forest into the present forest. Pennsylvania originally contained large, dense, and extremely pro- ductive forests. The large have become small, the dense have be- come open, the productive have become unproductive. Each genera- tion of mankind has seen a smaller, more open, and less productive generation of forests. The march of forest destruction has been rapid and severe and yet inevitable on account of existing economic conditions. While originally almost the total area of the State was covered with tree-growth, to-day less than 50 per cent, is covered by woody growth and over 5,000,000 acres of this is barren or un- productive, while many more acres are poorly stocked with trees. Most of our woodland areas are at present in a very unproductive unsanitary, unattractive, and unregulated condition. Economic conditions have changed and the old order of things need not continue. We must substitute conservative lumbering for the wasteful exploitation of the past. We must do constructive work in our forests now to recompense for the destructive work carried on during the last few centuries. We should aim to show our social and civic worth by handing down to future generations a heritage equivalent to that which we received from our forefathers. In order to do proper constructive work it is necessary to establish a goal or an ideal and develop proper methods by which it can be reached or at least approximated. We need not be entirely original in this work since a few countries like Germany, Switzerland, and Fran e have already in more than a century of experience laid the founda- tion for conservative and constructive forestry. We can learn much from these countries. A visit to their carefully managed forests together with a general survey of the methods which they use in managing them will be helpful in formulating plans for our Ideal or Normal Forest. We may not be able to adopt their methods but we can at least adapt them. The question at once presents itself: How can we improve our woodlands so that they will approach the well-managed forests of Germany, or the ideal or normal goal which we are setting up for them? The following answers suggest them- selves : 1. By giving adequate protection. Fire is the chief ajgency against which our forests need protection. 2. By procuring wise taxation. 3. By prohibiting unregulated cutting. 4. By securing quick reproduction after the removal of the timber. 16 5. By establishing a complete stock of valuable trees on all forest soils. 6. By removing undesirable stock and replacing it with a better class of trees. 7. By establishing a proper proportion and a suitable distribu- tion of age classes. 8. By making every part of the forest accessible by means of roads, lanes, trails, paths, compartment lines, etc. 9. By making improvement cuttings. 10. By dividing the forest into working units (compartments) just as a farmer divides his farm into fields and the fields into patches. THE FORESTS AND FORESTRY. The original forest was so modified by the activity of man, or man working conjointly with natural agencies, that the source of our future wood supply became a question of great importance. A gen- eral survey of the field showed that we were consuming wood faster than we were producing it. This unbalanced economic condition due to the unregulated condition of our forest gave birth to the sub- ject of forestry. Man's attitude towards the forest showed that he was a disturbing agent. Without him the forest of Pennsylvania would have remained practically undisturbed, indefinitely. Hence it might follow that the forest thrives best where there are no people, and consequently no forestry. Further, one often hears the state- ment: Formerly we had no forestry and plenty of wood; now we have forestry but no wood. This statement does not prove that for- estry is to be blamed for a deficiency in our wood supply, but it does prove that forestry is the child of necessity. This child of nec- essity, which is at present just in its formative period, could never have been born if we had not been compelled to see that our timber resources were rapidly decreasing. The word forestry to many may be new. The most enlightened may have a rather vague conception of its exact scope. It is often identified with the planting of individual trees, landscape work, and tree surgery. Forestry should be regarded as the rational treatment of our woodlands for their products. The kind of treatment de- pends largely upon the desire of the owner. The ownership may be private or there may be a public owner, as a municipality, a state, or a nation. The desire of the owner may be to supply wood ma- terial, to retain or establish a protective cover, to furnish recreation grounds, or to maintain a game cover. The forests which are man- aged for the purpose of producing a supply of woody material are known as production forests or supply forests, while those which Fig. 5. DENSE STAND OF NORWAY SPRUCE, GERMANY. The kind of forests we hope to develop. Norway Spruce is a valuable and a beautiful tree. ig. 6. CAREFULLY MANAGED FOREST. Attractive, sanitary, nroductive, and organized. Good roads ramify through all its parts. Fig. 7. FOREST ACADEMY STUDENTS IDENTIFYING TREES IN WINTER. Fig. 8. FOREST ACADEMY STUDENTS STUDYING THE GROWTH OF TREES IN A PLANTATION. Fig. 9. FOREST ACADEMY STUDENTS ESTIMATING TIMBER. 17 are retained or often established as a protective cover are known as protection forests. Protection forests aim to prevent calamities like destructive floods, excessive erosion, sand shifts, and snow shifts. Forests managed primarily to enhance the beauty of the forests and to furnish recreation grounds for the public may be known as park forests. Park forests should always be accessible to the public. Such outing grounds will not only be a means of preventing many of our diseases but also help to restore to health those who are already afflicted. Forests managed by the owner primarily to en- joy sport are known as luxury forests. Forestry aims to have man improve upon nature's ways of doing things. Nature grew forests upon areas regardless of the fitness of these areas to other more profitable pursuits. Both the thin, rel- atively sterile soils of the mountains and the deep, fertile soils of the valleys were covered with forests. The latter are far more valuable for the production of food material than for the production of wood material. Forestry aims to develop forests on forest soil. It does not attempt to encroach on agricultural soil but aims first to classify the land into ploughland and woodland; and then to treat the woodland areas so that they will yield the largest quantity of high class wood material in the shortest time at the least expense of time and money and to give to mankind as many other natural blessings as possible. The economic point of view should always be kept paramount. The forester's forest should supply more fully the pres- ent and prospective human wants than they can be supplied by de- pending upon nature's uncertain and unregulated performances. FORESTRY IN PENNSYLVANIA. Forestry had an early beginning in Pennsylvania. As early as 1681 William Penn in his Charter of Eights stated that "In clearing the ground care should be taken to leave one acre of trees for every five acres cleared; especially to preserve the oak and mulberries for silk and shipping." From this time on at irregular intervals acts were passed by the legislature protecting the woodlands from theft and firing; but no real, constructive work in forestry was done until the latter part of the 19th century. In 1855 F. Andre Michaux left a legacy of $14,000 to the American Philosophical Society in Philadelphia which became available in 1870 for forestry instruction. In 1877 Dr. J. T. Kothrock, Professor of Botany at the University of Pennsylvania, was appointed Michaux lecturer on Forestry, in which capacity he served until 1891. At this time it was difficult to interest the public in forestry and, as a consequence, at first, the lectures delivered by Dr. Eothrock were 2 18 not well attended. The interest in forestry, however, grew gradually and cumulatively. In June, 1886, the Pennsylvania Forestry Association was founded. It has always been and is still one of the best and most constructive organizations of its kind in America. In 1888 Governor Beaver appointed a Commission on Forestry, which was the first commission of its kind in this State. It presented a report to the legislature in 1889. The reports which this and the subsequent commission pre- sented to the legislature, together with the data obtained from the tenth census (1880), helped to stimulate interest in forestry on the part of both legislators and the public. In 1895 the Division of Forestry was created in the Department of Agriculture and Dr. J. T. Rothrock was appointed Commissioner of Forestry. He served in this capacity until June 1, 1904, when he resigned. Hon. Kobert S. Conklin, the present incumbent, succeeded him as Commissioner of Forestry. Under the direction of these able men the forestry work has progressed to such an extent in less than two decades, that Pennsylvania to-day stands in the front rank with reference to the development of its woodland areas. Many constructive acts pertain- ing to forestry have been passed by the legislature, some of which have served as models for other states. In 1901 the Division of Forestry was raised to a Department of Forestry. In 1903, by a special act of the legislature, the State Forest Acad- emy, at Mont Alto, was established. Mont Alto is a small village in Franklin county, sixty miles southwest of Harrisburg on the Cumber- land Valley Railroad. The ground occupied by the school buildings is a part of a State forest which affords an excellent opportunity for practical instruction and an accessible field for experimentation equalled by few if any forestry schools. Recently one of the leading forestry educators connected with an American University, a Ger- man by birth, in a public address said, "The Pennsylvania State Forest Academy has the best location and working field of any forestry school in the world." This school aims to train young men in prac- tical forestry so that they will be able to manage the State forests. Sixty-four men have been graduated, and most of whom are still in the service of the State. In addition to these foresters ninety-two rangers are also employed. A printed announcement of the school is available for free distribution and will be sent upon request. The State authorized the purchase of woodland areas in 1897 for the purpose of establishing State forests. To date (July 1, 1914) 998,773 acres have been acquired, located in 26 counties, at a total cost of $2,273,647.46, or an average of $2.27 per acre. This area is now being developed. Over 5,000 miles of roads, lanes and trails have been built, opened, or repaired. One hundred ninety-five miles of telephone lines have been built and numerous fire observation 19 towers have been constructed. The Department of Forestry aims to disseminate knowledge concerning forestry to the public, to protect carefully all State forests, to assist in the protection of private areas, and make accessible for management and utilization all State forests as rapidly as appropriations by the legislature will permit. Many large areas in various parts of the State are devoid of any valuable tree growth. Most of these areas are capable of developing useful forests. In order to have them developed it is necessary that such areas be stocked with valuable trees. It must be done by planting. About 6,000 acres have already been planted to trees in this State, which required a total of 11,970,500 seedlings. In order to produce these seedlings and to insure a future supply 4 large fores-t nurseries and 22 small ones have been established. Many other benefits are de- rived from the forests. They serve as recreation grounds to the public who seek their midst to regain or maintain health. Carefully managed forests regulate stream flow and are also the sources from which cities and towns obtain an excellent supply of unpolluted water. They furnish local labor, and, through permits, suitable camp sites to campers, hunters, and fishermen. The sale of material from the State forests has already yielded over |84,000, eighty per cent, of which will be set aside for "The State School Fund of Penn- sylvania." THE STRUCTURE OP THE FOREST. Every region and, often, even every small locality has its peculiar kind of forest. The composition of the forests along streams, on slopes, and upon mountain tops usually shows great differences. The climatic factors and physiographic features of a region influence the composition of the forest very much. The more varied the factors of the habitat are, the more varied the composition of the forest usu- ally is. Upon the same mountain slope one can often find three and sometimes more zones of trees. Each zone is composed of different species or groups of species, which groups vary not only in composi- tion, but also in form, density, and thriftiness. The forester seldom considers trees raised in isolated positions, but rather concerns himself with trees raised in masses or stands. Such masses of trees, irrespective of their kind, size, density, form, number, or value are known as woodlands. Woodlands may be com- posed of a single species or of two or more species. If one species composes ninety per cent, or more of the total stand it is known as a pure stand and if the stand is composed of two or more species none of which forms ninety per cent, of the total stand it is known as a mixed stand. Woodlands are rarely quite pure. A slight ad- mixture of some species is usually present. The forests of Pennsyl- 20 vania are decidedly mixed in their composition. The conifers are found oftener in pure stands than the broad-leaved species. Since the forests of this State are composed largely of hardwood species it is rather unusual to find pure stands. Occasionally one may find small pure stands of such species as Pitch Pine, White Pine, or Red Cedar and rather extensive ones of Chestnut. About 125 species of trees are native to the State of Pennsylvania but not more than 25 species are of sufficient importance to deserve to be developed in our future forests. A large proportion of our native trees is found as undergrowth. They form dense and some- times almost impenetrable thickets. This dense and complex struc- ture of our underwood aids considerably in increasing the number of participants in our forests. Dense and tall undergrowth tends to protect the soil from erosion, to conserve the fertility of the soil, and to afford shelter to birds which prey upon the insect enemies of the forest; but it may also impede the utilization of forest pro- ducts and make the tending of the forest more difficult. The tendency of forestry is to eliminate the undesirable species. We should eliminate cautiously since the despised species of to-day may be prized to-morrow. If this process of elimination is devel- oped on an intensive scale, it means a reduction in the number of species and, in extreme cases, leaves only one species, i. e. a pure stand. This is especially true where a forester aims to establish a stand by artificial seeding or planting. He is apt to choose a species, which he thinks will give the highest returns. If he selects the proper species and it is not injured during its development he may possibly obtain satisfactory results. Before establishing stands one should consider the subjoined advantages of pure and mixed stands. The principal advantages of pure stands are: — 1. Pure stands are easier and cheaper to establish. 2. Pure stands are easier to tend and manage. The principal advantages of mixed stands are: — 1. Mixed stands utilize the available plant food in the soil and air more fully. Close utilization of the factors of the habitat and keen competition by every forest tree upon its neighbor are requisites for optimum quantity and quality production. 2. The forester can meet the demands of the market better with a few species than with one species. 3. A larger number of trees per unit of area is usually found in a mixed stand than in a pure stand. 4. Many species are less subject to damage by wind, frost, fire, fungi, and insects, in mixture than when grown pure. 5. Trees usually develop a better form if mixed properly than if grown pure. 6. Mixed stands are more attractive than pure stands. 21 A great many pure stands may be seen in the forests of Germany. Some of them were established over 100 years ago and are now ready to be cut. After more than a century of experience in planting, the German foresters are abandoning the policy of establishing pure stands and are advocating mixed forests. Mixed forests may con- sist of a mixture by single trees or of a mixture by groups. The mix- ture may be temporary or permanent, even-aged or uneven-aged. We should aim to improve the composition of our forests by re- ducing the percentage of inferior species and increasing that of the more valuable ones. The present cover types which consist of many despised, some neutral, and a few prized species, should be transformed into the future management types which will be charac- terized by a simpler but superior composition. THE ESTABLISHMENT OP THE FOREST. As rapidly as the mature forests on absolute forest soil are re- moved they sould be succeeded by young forests. These new forests which follow in the wake of those removed may be established by one or by a combination of the following methods: — (1) Natural, where nature, aided to a limited extent by man, sows seeds and produces sprouts. (2) Artificial, where man sows the seeds or plants the seedlings. The former is usually spoken of as natural regeneration and the latter as artificial regeneration. In both methods nature does most of the work; but man helps nature more in the artificial method than in the natural method. Nature working through many centuries produced the original forest. We cannot wait for nature to produce another original forest on our forest soils. It will take too long. We may assist nature and attempt even to improve upon its way of doing things; but we must be careful that we do not de- viate too far from its methods for fear of being punished. In the case of artificial regeneration it is necessary to collect seeds from desirable trees. These collected seeds may be sown imme- diately or stored. If stored, they must be protected from such ani- mals as mice, squirrels, and birds, and from drought. The seeds may be placed between layers of sand to prevent drying out. Those seeds which are sown immediately may be sown directly upon the area where they are expected to germinate and establish themselves or they may be sown in beds in a nursery where they in time develop into seedlings. Direct sowing may be in the form of broadcasting, where the seeds are scattered rather uniformly over the area or spot planting, and where only isolated or scattered spots, often regularly spaced, are sown with seeds. The nurseries in which the seeds are sown may be permanent and located in the open, or temporary and located in the forest under the 22 shelter of trees. The nursery is divided into a great number of beds which are usually about twenty-five feet long and four feet wide. The seeds may be sown in these beds in spring or fall, either by sowing them broadcast or in rills. Here the seeds germinate and after an incubation period of usually less than a month, but occa- sionally extending over a year, they appear above the ground. The germination can sometimes be stimulated by soaking the seeds in water before planting. These young tender plants like children suc- cumb very readily to adverse conditions. Consequently they must receive careful treatment and adequate protection while they remain in the nursery. They must receive protection from the intense sun, excessive moisture, drought, weeds, fungi, and animals. The plants which develop from the sown seed may remain for one, two, or three years in the nursery. Those plants which remain for more than one year may be kept in the same place where the seeds which produced them were sown. If too dense they must be lifted and planted in another place where they will have more room. This process of lift ing the seedlings and planting them again is known as transplanting, and the resulting plants are transplants. Transplanting usually produces better plants because they are stockier and better prepared for the shock they will receive when planted in the forest. Species like White Pine, Red Pine, and Norway Spruce are usually left in the nursery for two or three years and then transplanted while other species like Ash, Walnut, and Oak are left in the nursery only one year. The seedlings planted in the forest are usually raised in nurseries but occasionally they may be taken from the forest floor where na- ture often produces them abundantly. The cost of raising plants in the nurseries varies with the species, cost and quality of the seeds, and the length of time left in the nursery, but is usually from about $2.50 to f4.00 per thousand. The source, method of collection, pre- paration, and' storage of the seeds have a marked influence on the quality of the resulting plants. The plants, taken from the nursery or lifted in the forest, are usually planted in the forest about 4x4 or 5x5 feet apart. This requires from about 1,700 to 2,725 trees per acre. The total cost of planting an acre of cleared land to forest trees, including cost of plants, is about $12. In individual cases the cost may exceed this figure and again it may be lower. This ar- tificial method of regeneration is generally used where forests have been clear-cut or where openings are to be reforested. It is also used for underplanting where a better humus covering is desirable. In Europe, especially in Germany, this method was used extensively during the last century as may be seen in the many even-aged forests found there at the present time. During the last decade a reaction has been setting in, based on scientific investigations. Many of the \l Fig. 13. DEVELOPMENT OF WHITE PINE SEEDS. Seedlings taken from nursery May, 1914, after growth had started. From left to right : Four seeds ; six seedlings from fall-sown seeds showing 3 stages of development directly after breaking through the ground ; two 1-year old seed- lings ; two 2-year old seedlings. Fig 14. STUDENTS PLANTING TREES. From 1,200 to 2,750 trees are planted per acre. A crew of 20 men can plant 20,000 trees per day if conditions are favorable. Fig. 15. NATURAL REGENERATION OF THE FOREST. Norway Spruce before seeding cutting. Opening the leaf-canopy stimulates seed production . Fig. 16. NATURAL REGENERATION OF THE FOREST. Norway Spruce after seeding cutting. Regeneration following regulated seed pro- duction. Fig. 17. NATURAL REGENERATION OF THE FOREST. Large Oak seed tree with its offspring. Fig. 18. NATURAL REGENERATION OF THE FOREST. An opening being filled by a dense growth of White Pine, Tulip, and Hemlock seed- lings, from seed scattered by bordering large trees Fig. 19. PLANTATION OF WHITE PINE. Six years, old from seed, about 2,000 trees, 2-3 feet high, per acre. Fit?. 20. PLANTATION OF WHITE PINE. Klovon years old from seed, about 2,500 trees, 5-12 t'eot high, per acre. 23 forests which were established artificially are now reaching maturity. Disadvantages of this method are becoming more evident and the foresters are gradually substituting the natural method for the ar- tificial. The natural regeneration of forests may take place in two ways: (1) By coppice and (2) by seed. By coppice is meant the shoots which spring up from the stump when the tree is cut (Figs. 23, 24, 69, 79) and the suckers which spring up from the roots. Coppicing is a rather important method of reproduction in Pennsylvania since some of our most valuable species, like Chestnut, Ash, and Oak re- produce readily by this method. Natural seed regeneration leaves most of the work to nature. Man attempts to hasten it somewhat by regulated cutting in the stand and by wounding the soil so that the seeds will find a favorable mineral soil upon which to germinate. The trees which produce the seeds may be scattered singly, or occur in groups, in strips, or in opened stands. These trees are known as seed trees or mother trees. Some form of natural regeneration must be used in protection forests, is advisable for game and park forests, and applicable to the forests which are managed for the production of wood. In some cases it is advisable to begin with natural regeneration and then fill in artificially all places which are not stocked with trees. THE DEVELOPMENT OP THE FOREST. The raising of some farm crops and the raising of a wood crop have many points in common. A farmer after planting his field to corn in spring does not leave it to nature to develop and mature, but he cultivates it and sometimes even cuts out undesirable sprouts called suckers, knowing that careful tending will result in a larger yield. Likewise the forester is not satisfied in establishing a forest but he also aims to develop or tend it so that it will yield a large and val- uable crop. The method of developing a forest depends upon the nature of the forest and the desire of the owner. The forest may have been es- tablished by nature and even partly developed by it or it may have been established by man. The forests established and developed by nature without the aid of man are usually in a rather unsanitary, unattractive, unproductive, and unregulated condition. Under such conditions it is necessary for man to transform these into forests which are clean, attractive, productive, and which show evidence of proper regulation on every hand. The forests which man establishes usually start out with 2,000 to 20,000 or even 50,000 seedlings to the acre, depending upon the method of establishment. If artificial methods of regeneration are used about 2,500 seedlings per acre are 24 required but where natural regeneration is used one may find 20,000 or even 100,000 seedlings per acre. If we go into a mature forest stand and count the trees per acre we will find probably 150, or some- times 250, and occasionally 400 ; hence, we must conclude that a large proportion of the trees which start out cannot survive. Two ques- tions suggest themselves: What happens with the large number of trees which cannot mature? Why is it necessary to plant so many when only a small number can mature? If one inspects a plantation of trees a few years after it was established he will be able to note a difference among the trees. Some are thrifty, which is shown by their rapid growth, others are average, while still others show no signs of growth whatever or may have died. If one returns ten years later this condition is still more pronounced. By this time they will have grown to such dimensions that their branches are beginning to interlace. A struggle has started between them. There is no longer sufficient space for all of them. They must battle with each other for light and food. Some will conquer and be known as domin- ant trees, while others will just about hold their own and be known as intermediate trees, while still others will be conquered and be known as suppressed or dead trees. This struggle for existence is found in all places where trees grow in the form of a forest, and re- sults in the elimination of the weaker specimens. At the same time it gives such drastic discipline to the dominant ones that they will produce a much higher grade of wood. Trees grown in dense stands are usually free from lateral branches for a consider- able distance from the ground and as a consequence the logs cut from them will be relatively free from knots; while trees grown in open stands or in open situations bear crowns which often reach almost to the ground and produce numerous knots. Such trees as the latter, consequently, yield an inferior grade of wood. In developing forests the owner or forester in charge should aim to maintain a proper number of trees per acre and to treat them so that they will not only yield a large quantity but also a good quality of wood. He should not aim to differ from nature's ways of doing things but improve on them. In order to improve the for- est it is necessary that the forester carry on certain operations in the immature stand which aim to improve the composition of the stand and the form of the individual trees. He should also aim to increase the rate ,of growth of the individual trees and as a result increase the yield in volume and value of the final product. The principal operations .which one must carry out in order to realize the above objects are: Cleanings, Liberation Cuttings, Thinnings, Damage Cuttings, Pruning, Weeding, and Underplanting. Cleanings are cutting operations in young rather even-aged stands which remove undesirable trees witli little prospective value, and Fig 23. THINNED CHESTNUT STAND. About 35 years old. Approximately 280 trees over 4 inches in diameter, breast high, still standing. Eight cords of wood per acre were removed. Fig 24. THINNED CHESTNUT STAND. About 22 years old. Average diameter of trees 5.5 inches. Approximately 650 trees per acre present. Over 90 per cent. Chestnut. Fig. 25. WHITE PINE STAND BEFORE AND DURING PRUNING, Fig. 26. SAME STAND AS FIG. 25, 10 YEARS AFTER PRUNING Fig. 27. OIL PIPE LINE AS A FIRE AND SUBDIVISION LINE. A base from which to fight fires. An excellent subdivision line. Fig. 28. COMPARTMENT LINE IN A YOUNG CHESTNUT FOREST. Such lines afford a base for controlling fires, and make the forest accessible. 25 favor other species with a good prospective value. These latter may have been overtopped by the undesirable ones. Liberation Cuttings are operations in immature stands in which the main crop of trees is overtopped by scattered older trees with very wide-spreading crowns. These older trees with present but little prospective value retard the development of a great number of younger trees with good prospective value. The removal of the larger trees is known as a Liberation Cutting. Thinnings are cutting operations in immature stands for the pur- pose of accelerating the growth of individual trees and, as a con- sequence, increasing the total yield and improving the quality of the product. Thinnings result not only in a larger quantity and quality increment but aim to improve the appearance and health of the forest. They decrease the danger from fire since a large amount of inflam- mable debris is removed. If thinnings are conducted properly the remaining trees are usually more windfirm. Thinnings also enable one to get returns upon a forest investment without waiting until the crop is finally harvested. Today, under our crude method of regu- lating the returns from our forests, the thinnings or intermediate yield play a minor role, while the final yield comprises practically the total yield ; but as our methods are developed and perfected, the intermediate yields will comprise as in the intensively managed for- ests of Germany, 25%, and later, 50% of the total yield. All forest owners should aim to improve their forest stands by thinning them properly so that they will become more attractive, more sanitary, and more productive. This may be accomplished by thinning early, regularly, and with increasing intensity, but always cautiously, so that the fertility of the soil will be conserved and all available food properly utilized. Damage Cuttings comprise operations which remove all damaged material from the forest. The damage may be caused by wind, light- ning, snow, insects, fungi, fire, or any of the many other agents which operate in the forest. Damage cuttings should be made as soon as possible after the damage is done not only in order to utilize the ma- terial before it depreciates too much in value, but also to prevent the spread of such destructive agents as insects and fungi. Pruning is an expensive operation and consists mainly in cutting off the lower branches of trees where they were not pruned natur- ally, in order to produce stems with as few knots as possible and at the same time increase the beauty of the stand. Underplanting is an intensive cultural operation which is practiced only under systems of intensive management of the forest. It may aim to conserve or even improve the soil or to establish advance reproduction. The aesthetic value of underplanting is also a valu- able asset in developing our forest. 26 Environmental influences and inherent tendencies are factors which are constantly discussed in connection with the development of our youth into useful men and women. These .same factors should be considered in developing the young seedlings of the present forest into the veterans of the future. THE PROTECTION OP THE FOREST. The protection of the forest surpasses in importance all other for- est activities during the early or formative period of forestry in any country. Forest protection is not only the oldest but also the most necessary branch of forestry. Many and varied are the destructive agents at work in the forest or upon the products derived from it. The destructive work of fire is very evident while that of fungi is often hidden. One cannot help but Comprehend the destructive work of a forest fire which may sweep over an entire mountain, kill every trace of tree growth, and, in addition, destroy buildings and oc- casionally human lives ; but few even apprehend the extent of damage by such agents as fungi which often cause the decay of the entire interior of a tree without giving any external evidence of their pres- ence. In order to give adequate protection to our forests, it is nec- essary to know the dangers which threaten them. We must also know how to offset attack by employing preventive and remedial measures. The principal dangers which threaten the forest and against which man must protect it may be grouped as follows: — 1. Damage from human agencies. 2. Damage from organic agencies. 3. Damage from inorganic agencies. Man's disturbing influence in the forest can be comprehended in part when one compares our present forests with those of the past. Primitive man had few wants, but as his civilization progressed his wants multiplied and his destructive tendencies became more ap- parent. The early settler found it necessary to destroy valuable forests for the purpose of establishing a home and for opening agri- cultural and grazing lands. He had no alternative then, but now conditions have changed. He is just at the beginning of forest ap- preciation. He must introduce system and substitute conservative forestry for destructive lumbering, which latter has always been characterized by profligate exploitation and wanton waste. Man is directly or indirectly responsible for most forest fires, since they usually originate through his carelessness or malicious- ness. Lightning is responsible for a very small percentage. Of all the enemies of the forest none is so destructive as fire. A single fire may burn over a few acres only or it may burn over thousands of acres in a single day. It not only destroys present but prospective value, since it consumes or kills mature trees and the young seed- Fig. 29. HEMLOCK TRUNK WITH FRUITING BODIES OF A FUN- GUS. Fig. 30. BLACK BIRCH TRUNK AT- TACKED BY TWO DIFFERENT SPECIES OF FUNGI. Fig. 31. CHESTNUT POST ATTACKED BY BROWN ROT (POLYPORUS SULPHUREUS) . Some fungi attack only living wood, others attack only dead wood. Fig. 32. WHITE OAK AND PINE LOGS ATTACKED BY FUNGI. The White Oak logs in foreground attacked by 3 different species of fungi. Cut about 8 months before photographing. The value has depreciated with exposure and fungous attack. Fig. 33. PRESIDENT JAMES BUCHANAN'S BIRTHPLACE. .Buchanan State Forest, Stony Batter, near Mercersburg, Franklin County, midal rough stone monument. Norway Spruce in the foreground. Pyra- 27 lings and saplings which would have produced the forest of the fu- ture. In the years 1907, 1908 and 1909, 2,455 fires occurred in the State of Pennsylvania, and burned over 484,987 acres. The esti- mated amount of damage was almost |1,000,000. It is also esti- mated that the average annual direct loss from forest, fires within Pennsylvania is |500,000. Three kinds of forest fires are usually recognized: Surface -fires, which burn the surface layer of leaves, grass, twigs, and some trees; Ground fires, which burn through soils with abundant vegetable ma- terial; and Crown fires, which burn through the crowns of trees. Many fires can be prevented by educating the people concerning the real value and significance of the forests. Vigilant patrol dur- ing the danger season, the construction of fire-towers, telephone lines, roads, fire-lanes, compartment lines, and the proper disposal of com- bustible material, help to minimize the fire danger. The damage which man does in the forest is very noticeable to his fellowman, while that done by other agents often goes unnoticed. Due to the development of our biological sciences in the recent past we are beginning to appreciate the extent of the damage done by such agents as insects and fungi. The organic agencies which damage the forest are plants or ani- mals. The principal types of plants which do damage to the forest or to the products of the forest are parasitic flowering plants, as the mistletoe, and fungi which cause the decay of wood. The extent of damage which fungi do to trees as well as construction timber is usually underrated. They may be found upon living or dead trees, stumps, logs, railroad ties, and construction timber in bridges, houses and barns (Figs. 29-32). The Chestnut Bark Disease is an example of a parasitic fungous disease which attacks the Chestnut tree, doing enormous damage. Many different kinds of animals do damage to the forest. Domes- tic animals, as cattle, sheep, goats, and hogs, and wild vertebrates, as deer, rabbits, squirrels, mice, and beavers, are among the most im- portant damaging agents. Next to fire, insects are the most destructive enemies of the forest. They may infest young seedlings in the nursery, the fruit or seeds, the twigs, the cambial bark, and the wood. They also do consider- able damage by attacking the leaves. Complete defoliation is not uncommon. The damage from inorganic agents may be in the form of wind- fall, wind-break, snow-break, excessive cold, excessive heat, shifting- sands, erosion, floods, and noxious gases. Proper protective measures can sometimes be carried out success- fully by the individual, but in other cases the co-operation of the nation, state, or municipality may be required. Organizations or 28 establishments for carrying out protective measures are also re- quired where large areas are to be protected. On July 1, 1914, there were employed in Pennsylvania 56 Foresters and 91 Forest Rangers to look after .the 998,773 acres of forest land which the State owns. Most of the foresters employed by the State received their training at the State Forest Academy. By developing the forest fire organiza- tion in Pennsylvania, forest fires will be rare events, as in the man- aged forests of Europe, and if they do break out will cause relatively little damage. THE VALUE OF FORESTS. Prior to the time that the conquest of Constantinople closed the route to the Orient, the Atlantic was regarded the world's back door. Columbus, a mere sea captain, to his own surprise, discovered a land which, as the old voyagers related, no one approached without appreciating the beauty of the forest. Those old voyagers appreciated the beauty of the forests but not their prospective value. The forests at first had a negative value. They were something which must be conquered. Their removal was necessary for the establishment of homes and the opening of agricultural lands. Thousands of acres of the best forests were simply burned to get rid of them. They were obstacles in the way of development. Gradually as our forest acreage decreased, as our population in- creased, and as the demand for wood goods multiplied, the forests be- came not only objects of interest and beauty, but also of value. After four centuries of rapid development we are just beginning to comprehend the real importance of our forests. They supply us with wood which is the most indispensable and universally used product of nature. Wood as a necessity or a luxury is used in our various activities from the cradle to the coffin. Many of our houses are built, finished, and heated with wood. Most of the paper upon which we write and upon which our books are printed is made of wood. The forests supply us not only with wood but with many minor products like maple sugar, tanning materials, naval stores, charcoal, wood alcohol, etc. Artificial silk and even whole suits of clothing have been made from wood. In addition, the forests furnish leaves for stable litter, pasturage, for cattle, pannage for swine, and great quantities of nuts which are used as food by man. Pasturage was formerly carried on more extensively than at present. It may be a legitimate industry if it pays and if it is so directed that the young seedlings in the forest, which will produce our future forests, are not eaten or injured. As a rule, grazing should not be permitted in 29 young forests where the shoots are still tender and readily eaten by animals, nor where the grazing animals may tramp out the seed- lings. The original forest may be regarded a great reservoir of wealth filled by nature working through many centuries, and exploited by man either for its products or to establish in its place a more neces- sary industry. The present forest on the other hand may be rep- resented by a much smaller reservoir only partly filled, and with material which is inferior not only to that found in the original forest but also far inferior to that which we hope to develop in the future forest. The present forest if properly managed, which im- plies improvement, is capable of producing continuously a large quantity of major and minor forest products representing an enor- mous value. In addition to the usual monetary value of forests we should also consider their value as soil formers, soil fixers, soil im- provers, preventers of floods, sanitary agents, suppliers of natural blessings, and beautifiers of the earth. THE VALUE OP TREES. Trees are among the commonest and most conspicuous objects of nature. They vary considerably depending upon their kind, their environment, and the artificial treatment which they may have re- ceived during their development. The trees which surrounded the simple home of the early pioneer differed very much from those which adorn the grounds of some of our wealthy citizens today, showing that nature, unaided by man produces trees in the forests which differ considerably from those which man has planted and cared for. Environment is a very potent factor which not only in- fluences the general appearance of a tree but also the structural parts which compose it. Trees as members of the forest stand have been considered in the preceding chapter. The subjoined material treats of trees used for purposes other than forestry. Trees are not only valuable for their products, as wood, resin, fruit, and litter, but in addition have an aesthetic and a protective value. Although tree-planting for shade and ornament has been practiced assiduously in past generations, yet the value of such plant- ing and the care which such trees require and should receive has not been fully appreciated until lately. Today individual trees or small groups of them are planted rather extensively about homes, along streets, in parks and public squares, for their shade and shelter. They are also used about the home to screen objectionable objects, to direct and restrict the views along general lines, to frame the home picture and to give the surroundings the expression of comfort and homeliness. The establishment and care of shade and ornamental trees is en- tirely different from the care of forest trees. Knowledge concern- ing the life-history of trees in general is, however, a prerequisite for the proper treatment of both classes of trees, but the art by which this knowledge is applied is entirely different. The forester grows trees to harvest and at harvest time he aims to obtain from them as much and as high grade wood as possible. The tree warden grows trees to preserve. He aims to develop a tree with as desirable an appearance as possible and to retain it as long as the vitality of the tree will permit. Thousands of dollars are spent annually by shade and park com- missions in developing the aesthetic side of our cities, towns, and many of our rural districts. The commissions or individuals who have this in charge, aim, by beautifying the environments, not only to improve the health and efficiency of the citizens, but also to raise their moral standard and hence increase their social worth. DECIDUOUS AND EVERGREEN TREES. All trees native to the State of Pennsylvania, when in a healthy condition, bear green foliage in summer. In autumn many of the green leaves change to brilliant colors, yellow, scarlet, deep red, or purple, and gradually fall to the ground. The species of trees whose leaves lose their green color and fall in autumn are known as deciduous trees. Most of the trees native to the State of Pennsyl- vania are deciduous. The deciduous trees are also known as hard- woods or broad-leaf trees. The Oaks, Maples, Birches, and Chest- nut are common examples of this group. Many of the representa- tives in this group yield valuable products and furnish interesting objects of study on account of their variation in form. In winter the deciduous trees are far more conspicuous than in summer since the dense leaf canopy is absent. This affords .an opportunity to study the trees with special reference to their form, branching, and bark. These characters are among the most helpful in distinguish- ing our common trees, especially since they are at hand at all sea- sons of the year. The leaves of a few deciduous species like the Beech and some of the Oaks die in autumn but often persist through the winter. Some species, however, do not shed all of their leaves in fall. Such trees are known as evergreen trees. The evergreen habit is char- acteristic for most trees commonly- known as conifers. Most of the conifers have needle-shaped leaves which persist for two or more years. The Larch, native to this State, and the introduced Bald Cy- press are, however, two species which shed all their leaves in fall and during the winter appear like dead conifers. The persistence of the 31 foliage of most of the conifers enriches the winter scenery and af- fords shelter for birds and other animals. Many conifers are highly prized for ornamental purposes and some yield valuable commer- cial products. The Pines, Spruces, Firs, Cedars, and Hemlocks are the commonest examples of this group. In addition to the conifers a few broad-leaf species, such as Khododendron, Mountain Laurel, and American Holly, are evergreen. A transition from the evergreen to the deciduous habit may be found in the Deciduous Holly and the Laurel Magnolia which are deciduous in the northern and evergreen in the southern states. The deciduous trees are commonest in the eastern part of North America while the evergreen are commonest in the western part. The former are usually found in mixed stands, while the latter often occur in extensive pure stands. The hardwood species usually occur on rather fertile soils while the conifers may thrive on more sterile ones. Both the deciduous and the evergreen habits have their ad- vantages. The shedding of the leaves in fall is a protective adapta- tion since it reduces transpiration, danger from snow-break, and damage from noxious gases. The evergreen trees have the advantage of lower summer transpiration and are ready at any season of the year for constructive activity. They are also less subject to damage by frost during the growing season. The advent of forestry may change the structure and distribution of our forests. The present tendency seems to be gradually and cumulatively in favor of the conifers. THE AGE OF TREES. Some trees reach great size and enormous age while others re- main small and die young. The size and age which a tree attains depend upon the inherent tendency of the species and the factors of the environment. Some species which naturally grow tall and be- come old may remain small under unnatural and unfavorable growth conditions. Other species never become large and old even under the most favorable growth conditions since it is inborn in them to remain small. A definite age limit cannot be fixed for each species but for general convenience we may classify our common trees as short-lived or long-lived. Of the trees native to the State of Pennsylvania the Oaks> Chestnut, Button wood, Tulip Tree, White Pine, and Hemlock may be regarded as long-lived tre*es, and the Pop- lars, Willows, most Birches, and some Cherries as short-lived. Some of the White Oaks found in the original forest of Pennsylvania showed an age of approximately 500 years. Some of the trees of this State reach a great age and enormous size, still none approach such 32 trees as the Big Cypress Tree of Tule found in the state of Oaxaca, Mexico, or the Sequoia of California. It is not always easy to tell the age of a tree or that of an even- aged stand of trees. Planting records are often very valuable in determining their exact age. The best means of finding out the exact age of a tree is to ask the owner who kept a record when the tree was planted. This method may be used for some ornamental trees and for forest stands which were artificially established. De- tailed records should be kept of all forest stands whether established artificially or naturally. The determination of the age of trees in the original forest or in an unregulated forest is a more difficult task. The age of a young tree like that 'of a child is more readily determined than that of an old tree. The best test for telling the age of a tree, if planting records are wanting, is to count the an- nual rings on a cross-section of the stem near to the ground and adding to this number, as many years as it took the tree to grow to that height. (Plate I, two lower series of drawings, and Plate XI, 1, 3). Each ring usually represents the growth of one year. A sec- ond test will apply to such species as White Pine, which develop their lateral branches in distinct and rather regular whorls. (Plate I, upper right figure, and Fig. 19). Each whorl normally represents a year's growth. If the branches have fallen off one can often find the scars of the branches on the stem. (See Frontispiece and Figs. 25, and 26). The age of young trees or small branches can also be determined by counting the rings of terminal bud-scale scars (Plate I, upper left figure). The portion of the branchlet from the end down to the first ring of bud-scale scars represents the last season's growth while that between the first and second rings represents the next to the last season's growth and so on. To tell the age of trees may sometimes be difficult but it is usually fascinating. After you have been successful in determining the age of a few trees, you may find yourself questioning the age of others as you walk or drive by them. A careful study of their growth will often indicate the successes and failures which they met during their development, since a relatively narrow ring often indicates a struggle, while a wide ring often indicates favorable growth conditions. THE FORM AND STRUCTURE OP TREES. 1. FORM : By form is meant the general appearance of a tree. One can study the form of deciduous or broad-leaved trees best in winter when they are devoid of their foliage. After one is familiar with the general form of different trees it is possible to distinguish the different species even at a great distance. The form, together with J years 4 years s yearj PLATE I. THE AGE OF TREES. m Fig. 34. OPEN GROWN PINES. White on left, Yellow on right. Both trunks excurrent and developed in same envir- onment. Difference of form is due to inherent qualities. One tapers, with per- sistent lateral branches; the other with little taper and few branches. Fig 35. OPEN GROWN AMERICAN ELM. Its trunk branches near the base and then repeatedly subdivides, known as a deliquescent trunk. Such a trunk is Fig. 36. FORM OF LOMBARD Y POPLAR. Fig. 37. FORM OF WEEPING WILLOW. Fig. 38. FORM OF A YOUNG PIN OAK. Fig. 39. FORM OF AN OLD PIN OAK. Fig. 40. FORM OF A SASSAFRAS. Fig 41. FORM OF A YOUNG OPEN GROWN TULIP TREE. Fig. 42. FORM OF A RED PINE. Fig 43 FORM OF A TABLE MOUN- TAIN PINE. It developed in a closed stand. Diameter 22 inches. 33 the color and figure of the bark, is a character by which many of our trees may be accurately distinguished. The form of trees varies with the species, the environment, and the sylvicultural treatment. Some trees attain an enormous size and great age while others never become large or old. The Sequoias of California, also known as Redwoods and Big Trees, and the Cypress trees of Mexico have representatives which are regarded the largest and oldest in exist- ence. A section of a Big Tree now in the American Museum of Natural History in New York City shows that the tree when cut was 1,341 years old. It was 90 feet in circumference at the base, over 350 feet in height, and estimated by lumbermen to contain 400,000 board feet of lumber. Probably the largest Cypress tree in the world stands in a churchyard about five miles from the City of Oaxaca in Mexico. This tree has a circumference, according to recent meas- urements, of 154 feet 2 inches, 6 feet above the ground. It is about 125 feet high and, according to various estimators, can scarcely be less than 4,000 years old, and may possibly be over 5,000 years. Specimens of this size and age have never been found in the State of Pennsylvania. Some of our native trees, the Chestnut, White Oak, Red Oak, Tulip Tree, Hemlock, and White Pine have, however, at- tained great size. A few large specimens which were cut in recent years, showed by count of their annual rings that they had started life before Columbus discovered America. In Forest Leaves, Vol. IX, No. 10, Dr. J. T. Rothrock describes a White Oak standing near Kutztown, Berks county. It was 31 feet in circumference at the level of the ground and had a spread of branches of 104 feet and an estimated height of almost 74 feet. This tree was probably the largest of this species in Pennsylvania. Larger specimens of Chest- nut have been found in this State. The largest Chestnut tree on record had a diameter of 17 feet. It was found near Waynesville, North Carolina. Other species like the Scrub Oak (Fig. 4), Gray Birch (Figs. 64 and 69), and Scrub Pine never become large. Some species may remain small in one region and yet become large in another. The Chinquapin w^hich reaches its northern limit in Penn- sylvania seldom exceeds a height of 10 feet in this State while it reaches a height of 50 feet in southern Arkansas. The character of the stem, to a large extent, determines the form of the tree. The main axis of a tree usually grows erect. The lateral branches vary according to the species and the position of neighbor- ing branches. In some species like the Weeping Willow (Fig. 37) they are drooping, in others like the Black Gum and Pin Oak (Fig. 38) they are horizontal, while those of the Lombardy Poplar are ascending (Fig. 36). If the terminal shoot is removed or killed a lateral branch in time may take its place. Sometimes two lateral 34 branches strive for thejteadership but they are such close competitors that neither can win out. The result is a "stag-headed" tree. Again a dormant bud may be stimulated into activity with the result that no lateral branch obtains the leadership. After studying these growth forms, one is inclined to think that the terminal shoot pre- vents the erect growth of the lateral branches. Environment has a marked influence. The form of a tree growing on an exposed mountain top differs very much from one growing on sheltered bottomland. An open grown tree has a form entirely dif- ferent from one grown in dense forest stand. The form of open grown specimens varies with the species. Two different species of Pine shown in Fig. 34 grew side by side in the same environment and still developed entirely different crowns. Open grown trees usually branch near the ground and have a broad, deep, symmetrical crown, while trees grown in dense forest stand usually branch far- ther from the ground and have a long clean trunk with a shallow and often irregular and unsymmetrical crown. Trees grown in a dense stand may not be so attractive as those grown in the open but they yield a much higher grade of wood, since the lateral branches which produce many of the knots in lumber are removed early in the life history of the tree. The density of the forest stand should be so regulated that on every acre of soil not only the greatest quantity but also the best quality of wood is produced. Two kinds of branching are usually recognized, the excurrent or upright and the deliquescent or spreading. When the main trunk is continuous and extends upward to the tip without dividing it is known as excurrent, and when the main trunk is not continuous but divides and subdivides into more or less equal parts it is known as deliquescent. Most of our evergreen species have the excurrent type of branching, while most of our deciduous trees have the deliques- cent type. A few of the latter, as the Pin Oak, Tulip Tree, ahd But- tonwood, often show an excurrent or upright tendency in the form of their trunk, especially when young. 2. BARK : If we examine the growing point of a seedling we will find that there is very little difference among the parts composing it. Soon, as a result of growth, various kinds of tissue will be formed. At the end of its first growing season we can differentiate roots, stem, and leaves. The stem is still further distinguished into pith, wood, and bark (Plate XI, 1.) Nature seems to know that the vital elements in the stem need protection. This protection is given by the bark. Bark is that portion of the stem which lies outside of the cam- bium layer. It consists of an outer and an inner part. The former is commonly known as the outer or dry bark and functions primarily Fig. 44. WHITE PINE. Trunk 25 inches in diameter. Fig. 45. RED PINE. Trunk 20 inches in diameter. Fig. 46. PITCH PINE. Trunk 22 inches in diameter. Fig. 47. YELLOW PINE. Trunk 29 inches in diameter. Fig. 48. JERSEY OR SCRUB PINE. Trunks 7 and 14 inches in diameter. Fig. 49. AMERICAN LARCH Trunk 18 inches in diameter. Fig. 50. BALSAM FIR. Trunk 16 inches in diameter. Fig. 51. BLACK SPRUCE. Trunk 14 inches in diameter. Fig. 52. RED CEDAR. Trunk 24 inches in diameter. Fig. 53. HEMLOCK. Trunk 22 inches in diameter. Fig. 54. AMERICAN HOP HORN- BEAM. Trunk 18 inches in diameter. Fig. 55. RED MULBERRY. Trunk 17 inches in diameter. Fig. 56. REDBUD. Trunk 8 inches in diameter. Fig. 57. BUTTONWOOD. Trunk 18 inches in diameter. Fig. 58. SWEET BUCKEYE. Trunk 32 inches in diameter. Fig. 59. HONEY LOCUST. Trunk 30 inches in diameter. Fig. 60. RED MAPLE. Trunk 8 inches in diameter Fig. 61. RED MAPLE. Trunk 30 inches in diametc Fig. 62. SUGAR MAPLE. Trunk 32 inches in diameter. Fig. 63. STRIPED MAPLE. Trunk 4 inches in diameter. Fig. 64. GRAY BIRCH. Trunk 4-9 inches in diameter. Fig. 65. RIVER BIRCH. Trunks 6 inches in diameter Fig. 66. SLIPPERY ELM. Trunk 26 inches in diameter. Fig. 67. SASSAFRAS. Trunk 26 inches in diameter Fig. 68. YELLOW BIRCH. Trunk 8 inches in diameter. Fig. 69. GRAY BIRCH. Trunk 4 inches in diameter. Fig. 70. BLACK BIRCH (Young.) Trunk 7 inches in diameter. Fig. 71. BLACK BIRCH (Old.) Trunk 27 inches in diameter. Fig. 72. RED OAK. Trunk 46 inches in diameter. Fig. 73. WHITE OAK Trunk 30 inches in diameter Fig. 74. BLACK OAK. Trunk 42 inches in diameter Fig. 75. ROCK OAK. Trunk 34 inches in diameter. Fig. 76. PIN OAK. Trunk 15 inches in diameter. Fig. 77. SWAMP WHITE OAK. Trunk 32 inches in diameter. Fig. 78. SCARLET OAK Trunk 14 inches in diameter Fig. 79. BASS WOOD. Trunks 8-14 inches in diameter. Fig. 80. BUTTERNUT. Trunk 20 inches in diameter. Fig. 81. BLACK WALNUT. Trunk 24 inches in diameter. Fig. 82. CHESTNUT. 'iiink 62 inches in diameter. Fig. 83. BLACK LOCUST. Trunk 18 inches in diameter Fig. 84. TULIP TREE. Trunk 21 inches in diameter. Fig. 85. CUCUMBER. Trunk 26 inches in diameter. H Fig. 80. WHITE ASH Trunk ',]() incites in dhntPter Fig 87. BLACK ASH. Trunk 22 inches in diameter. Fig. 88. SHAG-BARK HICKORY Trunk 26 inches in diameter. Fig. 89. PIGNUT HICKORY Trunk 22 inches in diameter. Pig. 90. MOCKER NUT HICKORY. Trunk 18 inches in diameter. Fig. 91. BITTER NUT HICKORY. Trunk 24 inches in diameter. Fig. 92. BEECH. Trunk 30 inches in diameter. Fig. 93. AMERICAN HORNBEAM Trunk 6 inches in diameter. Fig. 94. HONEY LOCUST. Trunk 10 inches in diameter. Fig. 95. LARGE-TOOTHED ASPENS. Trunks 16 and 18 inches in diameter. Fig. 96. WILD BLACK CHERRY. Trunk 6 inches in diameter. Fig. 97. WILD BLACK CHERRY Trunk 18 inches in diameter. Fig. 98. DOMESTIC CHERRY. Trunks 12 and 14 inches in diameter Fig. 99. TREE OF HEAVEN. Trunk 12 inches in diameter. Fig. 100. BLACK GUM. Trunk 22 inches in diameter. Fig. 101. PERSIMMON. Trunk 12 inches in diameter. Fig. 102. HACK HURRY. Trunk 8 inches in diameter. Fig. 103. FLOWERING DOGWOOD. Trunk 6 inches in diameter. 35 as a protective covering while the latter is known as the inner or living bark and helps to convey the food which was manufactured in the leaves to various parts of the stem. Thickness of the bark is often determined by the rapidity with which it peels off. Its thickness, together with its larger number of dead, air-containing cells, makes it a very effective protective covering; but the chief protective feature of bark is the formation of corky layers. The chief function of the protective covering in plants is the prevention of excessive transpiration. The regular cork formations in the bark help very much in controlling transpiration. Cork is one of the most valuable elements of the bark. Its structure is complex and vari- able. Cork is impermeable to air and water, a poor conductor of heat, and a preventer of penetration by parasites. Local out-growths of cork like the wings of the Sweet Gum and Hackberry are prob- ably of no value to the plants producing them. In some species the bark is not fully "ripened" at the end of the growing season, con- sequently the subjacent tissues do not have the necessary protection and frequently die back during the winter. The color of the bark varies in different species, in different situations, in different parts of the same species, and with the age of the trees. Young bark is usually green, but it soon loses this color due to the formation of cork and other substances. A few species like Sassafras retain their green color for a relatively long time due to deferred or late cork formation. Gray, brown, and black are the prevailing bark colors while red and white are also common. Color of the bark is very helpful in distinguishing many of our common trees. All the species of Birch native to Pennsylvania may be distinguished from each other by the color of their bark together with a few other bark char- acteristics. The bark on some of the older trunks becomes rough and then the characteristic color of the species may be present only on the branches and young stems. The outer bark may be uniform, mottled, or variegated in color. The interior and exterior parts of the bark may differ in color. Black Oak bark is yellow within and black without, while Hemlock is reddish within and brown to black without. The bark of the Buttonwood is peculiar since it is dark brown without and green, yellow, or white within. The inner bark often becomes very conspicuous due to the complete peeling off of the outer bark. Young branches and stems are usually smooth since the bark ex- pands sufficiently to accommodate the increased diameter growth of the interior. Later, in most species, the bark begins to crack, since the growth of the interior is too rapid for the expansion of the bark. In a few species like Beech, Blue Beech, and Balsam Fir the bark remains thin and smooth throughout life. Other species like Basswood and Pin Oak remain smooth for a long time but be- 36 come furrowed later, while many other species become rough early in life. The manner in which the bark cracks open or peels off af- fords a ready means of identification for many of our trees. The exfoliation of the bark is rather constant for each species. In some species like the Yellow Birch and Paper Birch it peels off in thin film-like papery layers. In the Shag-bark Hickory it is shaggy; in many species like the Pines and Spruces it is scaly; while in others like the White Cedar it is shreddy. Many species have furrowed bark. The furrows run usually in a longitudinal direction but may run transversely. The furrows or fissures separate ridges. These vary with the species. The fissures may be short or long, close or distant, narrow or wide, longitudinal, transverse, or diagonal. The ridges may be pointed or broad, high or low, smooth or scaly. The bark may be broken up into small square or rectangular blocks as in the Black Gum. This form of bark is often spoken of as "alli- gator bark." See Figures 44-103 for bark of most of our important native trees. The bark may be of considerable technical value. Hemlock and some species of Oak and Spruce have bark which is rich in tannin. The bark of these species is used extensively in the leather industry. The bark of a European species of Oak is highly prized on account of the large quantity of cork which it produces. The inner bark of some species yields dyeing material while that of others is used in the manufacture of fibre cloth. Formerly the bark of the Paper Birch was used in the construction of canoes. 3. TWIGS : Twigs are the terminal parts of branches. The term twig usually refers to that portion of the terminal part of the branch which grew in the last season. Those portions of the branch which began their growth a few seasons ago are usually spoken of as older twigs or branchlets. The twigs have their origin in the vegetative buds which may be located on the terminal end of the twig of the previous season's growth or along its side. If they emerge from terminal buds they become leaders, and if from lateral buds they will develop into lateral branches. The lateral branches may be alternate, op- posite, or whorled (Plate II). The method of branching is very help- ful in distinguishing our common trees. The lateral branches of most of them alternate with each other, while a fair number are opposite and a few whorled. The terminal twig elongates rapidly while the lateral ones usually remain shorter and occasionally are compressed to a stub or spur. When the vegetative buds burst open in spring young twigs, which are often covered with developing leaves, emerge from them. These twigs are, at first, usually delicate, greenish in color, and PLATE II. TYPES OF TWIGS AND PITH. 1. Tulip Tree (alternate branching). 2. Catalpa (whorled branching). 3. White Ash (opposite branching). 4. Gray Birch (slender and warty). 5. Staghorn Sumach (hairy). 6. Elderberry (lenticels prominent). 7. Black Cherry (lenticels transversely elon- gated). 8. Chestnut (lenticels small and numerous). Drawings are about one-half natural size. 9. Black Gum (lenticels few and inconspicuous). 10. Black Walnut (chambered pith). 11. Sumach (large pith). 12. Sassafras (medium-sized pith). 13. Oak (star-shaped pith). 14. Black Alder (triangular pith). 15. Common Locust (angular pith). 16. Elm (circular pith). 17. Birch (semicircular or irregular pith). PLATE III. TYPES OF BUDS. 1. Sugar Maple (opposite). 2. Chestnut (alternate). 3. Butternut (superposed). 4. Red Maple (accessory). 5. Striped Maple (stalked). 6. Striped Maple (valvate). 7. Red Oak (scaly). 8. Buttonwood (suh-petiolar). 9. Beech (solitary terminal). 10. Black Oak (clustered and hairy terminal). 11. Basswood (axillary and pseudo-terminal). 12. American Elm, showing (1) leaf buds and (f) flower buds. 13. Papaw (naked flower- and leaf-buds). 14. Common Locust (imbedded). 15. Trembling Aspen (sharp-pointed). Drawings are about one-half natural size. 37 often hairy. As they develop during the season they become firmer and often lose their green color and their hairs. The direction of the new growth is variable. In many species it takes at first a drooping direction and later, as its elements become firmer, it as- sumes a horizontal or ascending position. The new growth of the Pines is conspicuous in that it grows in an erect direction at first and later becomes horizontal or drooping. The taste, smell, and color of the twigs are helpful in distinguish- ing some of our common species. The twigs of some species as the Black Birch, Spice Bush, Sassafras, and Wild Cherry have a char- acteristic taste and smell. The color of the twigs may be green as in the Sassafras, red as in the Basswood and Red Maple, or brown as in the Sugar Maple. Many other different colors and combina- tions of color aid materially in distinguishing our trees. Some twigs are rough while others are rather smooth. They may be roughened by hairs, lenticels, raised leaf-scars, bud-scale scars, warty or resinous exudations, corky projections, or decurrent projections of the bark. If we examine a young twig just after it has emerged from the bud we will find that it is usually green in color. At the end of the first season's growth a thick bark has usually developed which is no longer green on the surface, but, by cutting a cross section of a twig, one will often find that the inner bark is still green. This green tissue develops chlorophyll and manu- factures food just as does the green tissue of the leaves. As the bark increases in thickness the chlorophyll decreases, eventually dis- appearing entirely from the stem. In order that this green tissue in the bark may function it is necessary that gases be exchanged through the bark. Special structural modifications on the bark known as lenticels (Figs. 96 and 98) make possible this exchange of gases just as the stomata on the leaf-surfaces allow and even regu- late the exchange of the gases of the leaf. The lenticels are very numerous and conspicuous on some species, while on others they are rare and inconspicuous. They are raised on some species like the Elder, while on others they are even with the bark. Their color varies. They may be white, gray, pinkish, yel- low, brown, or black. In outline they are usually circular or slightly elongated. In the Cherries and Birches they are confluent, a char- acteristic which results in the horizontally elongated lines of lenti- cels (Figs. 96 and 98) so common on their trunks. The duration of the lenticels varies with the species and its en- vironment. As a rule the more rapidly bark is formed the shorter is the duration of the lenticels. On some species it is difficult to find lenticels on any but the last season's growth while on others they may persist for some years. The exfoliation of the bark causes their disappearance. On a few species like the Birches, Cherries, and Honey Locust they persist for many years. The distribution of lenticels has not yet been systematized. They are distributed rather uniformly over the newer growth but are ir- regularly spaced. In some species they seem to be somewhat clus- tered just below the nodes and in others like Honey Locust they are more numerous on the lower side of horizontal branches. The pith usually occupies the central portion of twigs, branchlets, and roots. It is composed of thin-walled cells which are loosely ag- gregated. It seldom increases in size after the first year. The pith of a tree 100 years old is usually not wider than that in a year old twig of the same species. It becomes functionless early in the life of a tree. The pith of conifers is rather uniform in outline, structure, and color, but in the broad-leaved species it is very variable. In most species it is small in proportion to the size of the twigs, but in a few species like Sumach, Elder, Sassafras, Ailanthus, and Kentucky Coffee-tree it is relatively large. The outline in cross section may be 5-angled or star-shaped as in the Oaks, Chestnut, and Aspens, 3-angled as in Alder and some Birches, angular as in Common Locust, circular as in Elm, and ovoid as in Basswood. As a rule the pith is continuous, but in a few species like Black Walnut, Butternut, and Hackberry it is chambered. A few species like Catalpa have continuous pith except at the nodes where it is sometimes chambered. A less distinct separation of the pith is found in Black Gum, Papaw, Tulip Tree, and the Magnolias where plates of stone cells occur. The color of the pith may be white as in the Sugar Maple, pinkish as in Red Maple, brown as in Striped Maple, Mountain Maple, Sumachs, and Walnuts, red as in Kentucky Coffee-tree, or greenish as in Shad Bush. 4. BUDS : In temperate and colder climates the growing season extends over a part of the year only. During the warmer part of the year vegeta- tion is active, but as soon as the weather becomes cooler, many an- nual plants die while others make special preparation for the win- ter. One of the preparations is the formation of buds. They are formed in most trees and shrubs of cold and arid climates. If we examine a twig from one of our common trees in the month of July we can usually find buds starting to develop in the axils of the leaves. They continue to develop until they have reached a certain size, and then remain in an inactive condition for a few months in winter, only to become active again when favorable growth condi- tions return in spring. A year usually includes a period of rest alternating with a period of activity. Buds may be divided into 39 two classes, active and resting. Active buds are growing or develop- ing buds, such as one finds in late summer prior to the period of rest and early in spring when the resting buds have been awakened from their winter's slumbers. The resting buds are commonly known as winter buds (Plate III). Buds are protected growing points. The degree of protection given to the growing points varies with the species. A few of our trees and shrubs have buds which are nearly or quite destitute of a scaly covering. These are know as naked buds. The protection usually consists of scales which may be supplemented by hairy out- growths, resin, gums, or air spaces. These are known as scaly buds. The buds may be covered by numerous overlapping scales, known as imbricated bud-scales, or they may be covered by simply one or two visible scales which do not overlap. The buds of the Willows and Buttonwood are covered by a single visible bud-scale, while the buds of such species as the Striped Maple and the Black Alder have only two visible bud-scales whose margins simply meet and do not overlap. The latter are known as valvate buds. The buds may also receive protection from the enlarged bases of the stalk of leaves which often persist far into winter. The buds covered by the en- larged base of the leaf-stalk are known as subpetiolar buds. The buds of some of our common trees are very inconspicuous. It is often difficult to locate them when sunken so deeply into the bark that only the tip is visible. The size of the buds is not indicative of the size of the flowers or leaves which they will produce the fol- lowing season. Many of the trees which bear small and inconspicuous buds produce large and conspicuous flowers and leaves. The prin- cipal functions of the protective covering of buds are the prevention of the loss of water from the tender parts within and the protec- tion of their delicate interior from mechanical injury. Some add that the protection also minimizes the damaging effect of sudden temperature changes. The position of buds is of considerable value in distinguishing many of our trees and shrubs. They may occur at the end of the twigs or along their sides. The former are known as terminal buds and the latter as lateral buds. The terminal buds may be solitary as on the Beech or clustered as on the Oaks. On most of our trees and shrubs the lateral buds appear just above the origins of leaf- stalks and are known as axillary buds. They may occur in pairs, one on one side of the twig and the other exactly opposite, or singly forming a spiral around the twig. The former are known as opposite buds and the latter as alternate buds. The axillary buds may occur solitary or in groups, either one above the other, or side by side. If they occur one above the other they are known as super- posed buds and if they occur side by side they are known as accessory 40 buds. Sometimes axillary buds remain inactive for a long period of time without losing their vitality. Such are known as dormant buds. During their dormant period they remain on the surface of the trunk by the elongation of their connection with their point of origin. A superabundance of food, excessive light, or the death of a great number of terminally located buds, may stimulate them into activity again. A great number of these buds are often found along the stem of such species as Chestnut and Rock Oak. They develop into short branches which are known as "water sprouts." Some buds are produced at rather unusual points, and in irregular positions along the stem, and are called adventitious buds. They also form "water sprouts." One finds a wide variation in the size and form of the buds which our common trees produce. Some are long and slender; others are short and stout. Some of them are round in cross-section; others are angular. Some are sharp-pointed; others are blunt-pointed. The buds also vary in the manner of their insertion on the twigs. Some are inserted directly on the twig; others are separated from the twig by a stalk, and still others may be almost entirely covered by the twig. The former are called sessile buds, the next stalked buds, and the latter imbedded buds. The kind of buds which a tree produces is of considerable import- ance, especially where fruit trees are considered. Three principal kinds of buds may be distinguished: — leaf buds, also known as vege- tative buds, the contents of which will develop into stem and leaves; mixed buds, the contents of which consist of leaves and flowers in their formative stage; and flower buds, also known as propagative buds, which contain the elements of flowers only. How can one find out what kind of buds are at hand? The buds may be cut open by means of a sharp knife and their contents studied with the aid of a magnifying glass. One may also take a twig and place it in a jar of water in a warm room and in about a week the buds will have expanded far enough to reveal the nature of their contents. The twig with its buds may also be left on the trees and its development observed in spring when nature opens them. With all this varia- tion in the position, insertion, form, structure, and kind of buds we still find here, as in all nature, law and order. 5. LEAVES : The shoot of a seed plant consists of stem and leaves. The leave^ of our common trees are excellent distinguishing characters by which the species may be recognized. They are variable in form. This variation, as well as the work they do, is little appreciated by the crowds which annually seek their shade and shelter. This chapter PLATE IV. TYPES OF LEAVES. 1. Black Cherry (simple). 2. Common Locust (compound). 3. Chestnut (alternate arrangement). 4. Sugar Maple (opposite arrangement). 5. White Pine (5-clustered). 6. Pitch Pine (3-clustered). 7. Jersey or Scrub Pine (2-clustered). 8. Larch (many clustered). 9. Larch (many clustered at base; solitary on leading shoots). Drawings are about one-half natural size. 10. Red Spruce (4-sided). 11. Balsam Fir (flat and sessile). 12. Hemlock (flat and stalked). 13. Red Cedar (scale-like needles). 14. Arbor Vitae (scale-like needles). 15. Arbor Vitae (section enlarged showing glands on leaves). 16. Red Cedar (awl-shaped needles). LEAF FCPM3 Br/^f/e -pointed PLATE V. TYPES OF LEAVES. 41 aims to give a general description of leaves and a brief outline of their work. A typical foliage leaf consists of three parts: (1), the Wade or flattened portion (lamina) ; (2), the leaf-stalk (petiole) ; and (3), the leaf -appendages (stipules). t Two kinds of leaves are usually recognized: — simple and com- pound (Plate IV). Simple leaves have blades which are more or less united into one piece, while in compound leaves each leaf is composed of a number of smaller leaflets. Compound leaves may have all the leaflets originate from one point as in the Buckeyes (Plates CXII, CXIII), or scattered along the main petiole as in the Common Locust (Plate XCVII). Each prima^ division of a compound leaf may again be compounded as in the Kentucky Coffee-tree (Plate XCIV). Such a leaf is known as a doubly compound leaf. The arrangement of the leaves on the twigs and branches of our common trees may be alternate, opposite, or whorled (Plate IV). When the arrangement is alternate, the individual leaves are located singly at a node; when opposite, two leaves occur opposite each other at a node; and when whorled, more than two leaves occur at a node and are distributed regularly around the twig. In a few species as the Birches, the leaves of the lateral spurs appear to be opposite, but upon closer examination they are found to be alternate. The leaves of the trees native to. this State may be classified as follows: (1), Trees with needle-shaped leaves, known as conifers or evergreens, and (2), trees with broad leaves known as hardwoods or deciduous trees. The needle-shaped trees show a wide variation in the form and distribution of their needles. They may occur singly, in fascicles of 2, 3, or 5, or in clusters on lateral spurs; they may also be stalked or sessile, scale-like or awl-shaped, and flat, semi-circular, triangular, or four-sided in cross-section. The broad- leaved trees have an even wider variation in form. This may be in part due to the greater number of representatives belonging to this order. A few of the commonest leaf forms are shown on Plate V. Other intermediate forms are commonly found among our trees. The size of the leaves varies as much as their form. They may be small, scale-like, or awl-shaped as in the Arbor Vitae and Common Jumper respectively, or large and tropical-like as in the Magnolias and Papaw. The point, or apex, of leaves varies with the species and the gen- eral leaf-form. The commonest kinds of points recognized are shown on Plate V. The bases of leaves are also often characteristic and of consider- able value in distinguishing species, since different species may have th'e same general form but different bases. The commonest kinds of bases recognized are shown on Plate V. Intermediate forms may 42 readily be found, since leaves taken from the same tree or branch often show a wide variation. The margins of leaves are often more variable than their apexes and bases. The kinds most commonly recognized are shown on Plate V. The figures represent the margins' of simple leaves, but the margins of the leaflets of compound leaves follow the same ter- minology. Most of the leaves of our common forest trees contain a rather complicated system of fib ro- vascular bundles. These fibro-vascular bundles, known as veins, form the framework of the leaves. Sur- rounding and between these veins is found a green pulpy mass, the spongy parenchyma. The whole body of the leaf is covered by a protective covering known as the epidermis, the thickness of which varies with the species of tree and the climate. One can find variations in the petiole and stipules of leaves as well as in the blade. The petiole may be absent, short, or long. When the petiole is absent the leaf-blade is sessile. It may also be enlarged at the base, circular, heart-shaped, flat, or triangular in outline. The enlarged base may be hollow or clasping. The stipules are usually not very conspicuous. In many species they persist for a short time only and then fall off. The main function of the stipules is protection, but a special modification of the stipules is seen in the Common Locust (Plate XCVII), where the thorns are modified stip- ules and function as mechanical protectors. Leaves are the most industrious organs of a plant. They work day and night from early spring until autumn. The four chief func- tions of leaves are: (1) Photosynthesis; (2) Kespiration; (3) Transpiration, and (4) Assimilation. Photosynthesis is the process by which the leaf manufactures starch or sugar from carbon dioxide and water with the aid of the energy of light. That green plants require light for their growth and development is shown by the man- ner in which the axis and their leaves adjust themselves so as to re- ceive the greatest amount of light. By respiration in plants is meant the process by which oxygen is consumed and carbon dioxide and water are given off. It is primarily a process of oxidation and re- sembles in general the process of respiration as found in man and higher animals. In order to facilitate this exchange of gases the plants are supplied with openings on the leaf surfaces, especially on the lower surface, and on the bark. The openings on the leaf sur- faces are known as stomata and those on the bark as lenticels. Each slit-like opening on the leaf is surrounded by two guard cells which are somewhat complicated in structure and very sensitive to changes in temperature and water supply. They function primarily as breathing pores and as outlets for the water vapor given off during the process of transpiration. Their number varies, but it has been PLATE VI. TYPES OF LEAF-SCARS AND BUNDLE-SCARS, 1. Tulip Tree. 2. Catalpa. 3. American Hornbeam. 4. Sassafras. 5. Persimmon. 6. Maple. 7. Poplar. 8. Red Mulberry. 9. Buttouwood. 10. Chestnut. 11. Walnut. All drawings are slightly enlarged. 12. P.asswood. 13. Birch. 14. Box Elder. 15. Papaw. 16. Horse Clii'stmil. 17. Dwarf Sumach . 17a. Stagliorn Suma< h. IS. Hercules' Chili. 19. Sour- wood. :o. Kentucky Cofl'ee Tree. .'1. A*l\. PLATE VII. FLOWERS AND FLOWER ARRANGEMENT. 1. White Pine (staminate cluster), x J. 2. White Pine (2 pistillate), x J. 3. Willow (staminate ament), x J. 4. Willow (pistillate ament), x \. 5. Walnut (staminate ament), x J. 6. Walnut (a pistillate flower), enlarged. 7. Hickory (staminate ament), x \. 8. Hickory (a pistillate flower), natural size. 9. Birch (a staminate ament), x J. 10. Birch (a pistillate ament), x J. 11. Beech (a staminate head), x J. 12. Beech (two pistillate flowers), natural size. 13. Chestnut (a staminate ament), x J. 14. Chestnut (a pistillate ament), x J. 15. White Oak (4 staminate aments), x J. 16. White Oak (a pistillate flower), enlarged. 17. Elm (3 clusters of incomplete flowers), x i. 18. Mulberry (a staminate spike), x i. 19. Mulberry (a dense pistillate spike), x J. 20. Tulip Tree (a complete flower), x j. 21. Papaw (a complete flower), x 1. 43 estimated that the lower leaf surface of Black Walnut contains about 300,000 per square inch. The leaf is not only peculiarly modi- fied for the reception of light and the absorption of gases, but also for the loss of water. This process of losing water in the form of vapor through the stomata is known as transpiration. The large amount of water given off by trees is usually not appreciated. The Austrian Forest Experiment Station has published data which show that an open-grown birch tree with 200,000 leaves transpired on hot summer days from 700 to 900 pounds. Assimilation, the fourth of the functions named above, comprises a series of changes which are necessary to transform the raw or newly manufactured food material into actual plant tissue. 6. LEAF-SCARS AND BUNDLE-SCARS: Most of our trees and shrubs, except the cone-bearers, shed prac- tically all their leaves in autumn. Those which shed their leaves in this manner are known as deciduous trees, while those which re- tain them for two or more seasons are known as evergreen trees. When the leaf falls a scar is left at the point of its insertion. The leaf-scars vary in size, form, position, occurrence, and the number of vascular bundles which they contain (Plate VI). They may oc- cur singly, in pairs, or in whorls, just as the leaves which precede them. They appear at points on the twigs known as nodes. The portion of the twig between the nodes is called the internode. They may be large, medium, or small in size depending upon the species. If they occur in pairs on opposite sides of the twig they may be so large that they completely encircle the stem, or only a portion of it. Their form may be round, oval, elliptical, heart-shaped, shield- shaped, crescent-shaped, lobed, or triangular. They may be raised, depressed, or even with the surface of the twig. Their surface may be flat, concave, smooth, or wavy. The leaf -scars contain bundle-scars. The bundle-scars mark the position of the vascular bundles which formed a connection between the leaves and the twigs. They carry liquid material to and from the leaves. Two distinct portions may be distinguished in these vascular bundles ; the woody portion which serves to carry water into the leaf, and the sieve-tube portion which serves to carry plant food from the leaves where it was manufactured, down into the twigs, branches, and stem. These bundle-scars vary in size, form, and num- ber in a leaf-scar, and the manner in which they are distributed. Some of our common forest trees have only one bundle-scar in a leaf- scar, while many have three, and others four, five, to many. The number is constant in some species and variable in others. The in- dividual bundle-scars usually are circular in outline but may be linear, crescent-shaped, or irregular. Where more than one is found 44 in a leaf-scar they vary in their arrangement. They may form a closed ellipse, a lunate line, a double line, a V-shaped or a U-shaped line, or they may be irregularly scattered over the leaf-scar, or grouped in clusters. A number of bundle-scars may sometimes be grouped so close together so as to form a compound bundle-scar or a line of confluent bundle-scars. The leaf -scars together with their bundle-scars are excellent characters with which to distinguish many of our common forest trees during winter when most of the distinguishing characteristics which one can use in summer are ab- sent. By carefully studying these characteristics, together with others, it is as easy to distinguish the forest trees in winter as in summer when the foliage is present. 7. FLOWERS : Sometime in their life history plants usually give rise to others of their kind. The method which they use to accomplish this varies with the species or the group. Most of our trees develop flowers whose chief function is pollination, the initial step in the production of seeds. The existence of flowers is consequently for the good of the plant and not for the good of man, even though their beautiful forms and colors do please his fancy and make his life happier. The flowers of our common trees vary considerably in form, struc- ture, and color (Plates VII, VIII). Most of them are very modest in appearance while a few of them are conspicuous on account of their large size and brilliant color. In speaking of the flowers of our trees collectively, one often hears the phrase "The uncommon flowers of our common trees." The truth of this phrase becomes clear when we think of the small and inconspicuous pistillate flowers which such trees as the Oaks, Birches, American Hop Hornbeam, Walnuts, Hickories, and others produce. A few species like the Magnolias, Cherries, Dogwoods, Tulip Tree, and Basswood produce rather conspicuous flowers. The parts of a flower are of two general kinds — the essential organs which are concerned in the production of seeds and the floral en- velopes which act as protecting organs. The essential organs con- sist of two series, — the outer which is composed of stamens and bears the pollen, and the inner which is composed of pistils and bears the seeds. The floral envelopes also usually consist of two series, — the outer which is composed of sepals, collectively known as the calyx, and the inner which is composed of petals, collectively known as the corolla. The corolla is usually the showy part of a flower while the calyx is usually green in color. A flower which has calyx, corolla, stamens, and pistils is said to be complete. If any part is wanting it is incomplete. When both the floral envelopes are wanting it is naked. A flower in which the pistils are lacking is known as a staminate flower, while one in PLATE VIII. TYPES OF FLOWERS. Sweet Gum (staminate bead*), x J. , . Sweet Gum (a pistillate Lead), x J. Common Locust (a drooping raceme), x i. Striped Maple (a drooping staminate raceme), x |. Striped Maple (a drooping pistillate raceme), Ufl Maple (staminate fascicles), x J. Red Maple (pistillate fascicles), x J. BttWWOOd (a drooping crme), x |. Flowering Dogwood (a dense cluster). White Ash (a staminate panicle), x J. White Ash (a pistillate panicle), x 4. Rhododendron (a single flower), x J. 13. Wild Black Cherry (a raceme), x |. 14. Button wood (a head), x J. x J, PLATE IX. TYPES OF FRUIT. 1. White Pine (cone), x \. 2. White Pine (winged seed), natural size. 3. Willow (capsules), x J. 4. Willow (a winged seed), enlarged. 5. Trembling Aspen (capsules), x 5. 45. Trembling Aspen (a winged seed), enlarged. 7. Black Walnut (a nut with indehiscent husk), x i. 8. Hickory (a nut with dehiscent husk), x 1. 3. American Hornbeam (a nut with 3-lobed bract), x J. 10 American Hop Hornbeam (a nut inclosed in bladder-like bract), x J. 11. Black Birch (a membranous strobile), x j. 12. Black Alder (a woody strobile), x J. 13. Beech (a nut with prickly bur), x i. 14. Chestnut (u nut with spiny bur), x J. 15. Red Oak (an immature acorn), x J. 16. Red Oak (a mature acorn), x \. 17. Red Mulberry (an aggregate fruit), x 1. 45 which the stamens are lacking is known as a pistillate flower. Some- times the staminate and pistillate flowers are not only found on dif- ferent parts of the same tree but on entirely different trees. The chief role of flowers is pollination. Pollination is the transfer of pollen from the anther of the stamen to the stigma of the pistil. When pollen is transferred from the anthers to the stigma of the same flower it is known as close-pollination, and when pollen is trans- ferred from the anthers of a flower of one plant to the pistil of a flower of another it is known as cross-pollination. Wind and in- sects are the chief agents which carry the pollen in the case of cross- pollination. The flowers of the Tulip Tree, Papaw, and Cherries, are examples in which close-pollination can take place, while the flowers of the Willows and Poplars are good examples in which cross-polli- nation takes place. When the staminate and pistillate flowers are on the same plants e. g. Oaks, American Hop Hornbeam, Beech, Chestnut, Hickories, and Walnuts, the plants are known as monoecious and when they are on different plants as in the Willows, Poplars, and occasionally some Maples, they are known as dioecious. Flowers vary not only in the size, form, shape of their parts, and color, but also in their arrangement. In a few cases the flowers of trees like the Tulip Tree and Papaw are borne singly and known as solitary -flowers. The flowers may also be arranged in clusters like that of the Lily of the Valley or the Wild Black Cherry (Plate VIII, 13). Such an inflorescence is known as a raceme. A raceme may be compact as in the Wild Black Cherry; or loose as in the Common Locust (Plate VIII, 3) and the Striped Maple (Plate VIII, 4-5). When the flower cluster is dense and the flowers sessile, or nearly so, it is known as a spike. Spikes may be 2-5-flowered as in the pistillate flowers of the Hickory (Plate VII, 8), or densely flowered as in the staminate flowers of the Mulberry (Plate VII, 18). A very short and dense spike is known as a head (Plate VIII, 14). A spike is sometimes short, flexible, and rather scaly as in the Willows, Poplars, and rather long as in the staminate flowers of the Oaks, Hickories, Birches, and Alders (Plate VII, 7, 9 and 15). Such a spike is known as an ament or catkin. Other types of inflorescence are the umbels (Plate LXXXVII), panicles (Plate VIII, 10-11), and corymbs. The time at which the flowers appear and their duration varies with the species. The Alders, Hazlenut, and some Maples produce their flowers early in spring before the leaves are out. Others pro- duce them with the leaves, while still others produce them after the leaves. The Witch-hazel produces its flowers late in fall. It is the last of our trees to blossom. 46 8.- FRUIT: Sometime after pollination the egg cell or ovule is fertilized, and as a result of fertilization, the ovule, together with the surround- ing ovary, enlarges. The enlarged ovules, together with inclosing ovary, form what is termed the fruit. The fruit may in addition comprise modifications of other organs intimately connected with the ovary. Seeds are products of the flower and are usually regarded as reproductive organs, but in reality they are the result of reproduc- tion. Their chief work is the dissemination and the protection of the offspring of reproduction. They are usually covered by hard and impermeable coats which protect the young plant contained within from the many dangers with which it is beset. Nature tries to guard against these dangers by developing suitable protective cover- ings for each species. Nature, however, is not always satisfied by simply developing a thick and impermeable coat, but in addition it develops an internal tissue which is compact and contains little water. If a seed possess these essentials it is well protected against most of the destructive agencies to which it is exposed. The chief dangers to which seeds are subject are premature germination, loss of vitality, and destruction by animals. Each seed usually has a suitable covering which regulates the germination in spring. This regulation is necessary so as not to allow the tender plant to emerge before the external growth conditions are favorable for its develop- ment. An embryo within a thin-coated seed would often be stimu- lated by a few warm days in spring with the consequence that the resulting tender plants would be killed by later frost. Nature acts as a guardian and places a thick coat around such embryos, and as a result they are not stimulated until later when frost danger is past. Food is stored in various plant organs such as roots, stem, and branches, and is usually most abundant and conspicuous in the seeds. It occurs in various forms and may often differ in composi- tion. Food stored in the seed is very valuable because it supplies nourishment to the small and tender plants before they have de- veloped the roots with which they draw nourishment from the soil and supply water to the leaves where starch and sugar are manu- factured. Primitive man obtained considerable food from the seeds of trees, and present man derives certain foods for himself and his animals from some of our common trees. The food value of seeds varies with the species. Some species like the Willows contain very little food, while others like the Chestnut are rich in food. The time at which the fruit matures varies with the species. Wil- lows, Poplars, and Elms mature their fruits in spring; others, like PLATE X. TYPES OF FRUIT. 1 Osage Orange (a compound drupe), x J. Hackberry (a drupe), x J. American Elm (one-seeded samara), x |. Tulip Tree (a light brown cone composed of many carpels), x J. 5 Papaw (a fleshy or pulpy fruit), x j. (3. Sugar Maple (paired samara), x J. 7. Wild Black Cherry (a drupe), x J. 8. Basswood (a nut-like drupe), x \. 9. Sweet Gum (multicapsular head) , x 5. 10. Persimmon (a juicy berry), x J. 11. White Ash (samaras), x I. 12. Kuttonwood (a head), x *. PLATE XL THE STRUCTURE OF WOOD. 1. Cross section of six-year old stem of White Pine showing (b) bark, (c) cambium, (ar) annual ring, (p) pith, and (rp) numerous smail circular resin passages, natural size. 2. A resin passage with bounding epithelial cells, enlarged. 3. Non-porous wood of White Pine showing (spw) spring wood, (sw) summer wood, (ar) annual ring, and (rp) resin passage, x 3. 4. Ring-porous wood of Chestnut, x 2. 6. Ring-porous wood of Red Oak, showing large medullary rays, x 3. 6. Diffuse-porous wood of Beech, x 4. 7. Block of Chestnut wood showing (cs) cross section, (rs) radial section, (ts) tangential section, (spw) spring wood, and (sw) summer wood, natural size. 47 the Cherries, Mulberries, and some Maples, in summer ; but most of them, like the Oaks, Chestnut, Pines, and others, in autumn. The seeds of some species like the Willows die unless they germinate soon after they mature. Most species retain their capacity to germinate for several months or several years, while a few members of the Pulse family are reported to retain their vitality for more than 325 years. The mature fruit and seeds of our common trees show a wide variation in their form and structure. Fruits are usually classified on the basis of their texture, as fleshy fruits and dry fruits. Fleshy fruits are represented by the fruits of such species as Cherries, Papaw, Osage Orange, etc. (Plate X, 1, 2, 5, 7, 10). Dry fruits are those which do not have any flesh or pulp, and are represented by the fruits of such species as the Maples, Ashes, and Oaks (Plate IX, 1-16, and Plate X, 3, 4, 6, 8, 9, 11, 12). Fleshy fruits including the stone fruits, are indehiscent. Indehiscent fruits (Plate X, 1, 2, 5, 7, 10) are those which do not split apart regularly along certain lines for the liberation of the seeds, while dehiscent fruits do split open. Dry fruits may be indehiscent or dehiscent. The following general types of fruits are commonly recognized: the pome (Plate XOII), the drupe (Plate X, 7, 10), the nut (Plate IX, 7, 8, 9, 14, 15), the samara (Plate X, 3, 6, 11), the follicle (Plates LXXVI-LXXVIII), the capsule (Plate IX, 3, 5) and (Plate X, 9), the legume (Plates XCIV-XCVII), the cone (Plate IX, 1) and the collective or aggregate fruits, (Plate IX, 17). The species belonging to a single genus usually produce a common type of fruit, but genera belonging to the same family often have an entirely different kind of fruit. This difference of fruit of genera in the same family is shown very clearly in the Nettle family, to which belong the Elms, Hackberry, Osage Orange, and Mulberry, whose fruit are shown on Plate X, 3, 2, 1, and Plate IX, 17. A wide variation may also occur within the general types mentioned above. The nut is one of the commonest types of fruit found in the forest and will possibly show this wide variation best. Nuts may be small and light, as in the Buttonwood and Birches, or large and heavy as in the Oaks and Chestnut. Light nuts often have appendages attached to them in the form of a membranous wing or a tuft of hairs. The nuts may be produced singly or in strobiles as in the Birches and Alder. They may also be covered or naked. If covered, the covering may be indehiscent and semi-fleshy (Plate IX, 7), or dehiscent and dry (Plate IX, 8). It may also consist of a stalked prickly dehiscent bur (Plate IX, 13), a large spiny dehiscent bur (Plate IX, 14), a bladder-like bag (Plate IX, 10) or a leafy involucre, as in the Com- mon Hazlenuts (Plate LI). In some species the seeds are not cov- ered entirely but simply subtended by a leafy bract (Plate IX, 9). 48 In the Birches a.nd Alder the small winged nuts are produced on 3- lobed bracts which are so arranged that they form a cone-like fruit- ing body known as a strobile. It is rather hard to classify the fruits of some species in terms of the types enumerated above, e. g., the fruit of the Basswood has the appearance of a nut, but is in reality a drupe; while the fruit of both the Mountain Ash and the Shad Bush has the appearance of a berry but is actually a pome. A super- ficial examination is often not sufficient to determine the type of fruit. The fruit of our common Sumachs is a drupe, but is usually covered with acid hairs, so that it is difficult to recognize the type of fruit to which it belongs. After the fruits and seeds have been produced, it is necessary that they be scattered on a mineral soil upon which they may germinate. The distance over which they are scattered may be short or long, depending upon the nature of the seeds and the agents by which they are dispersed. The fruit, as a whole, is usually scattered in the case of indehiscent fruits, while the seeds only are scattered in the case of dehiscent fruits. The drawings on Plates IX and X show various structural modifications of fruits and seeds which aid in their dis- persal. The chief dispersal agents are propulsion, man, animals, water, wind, and gravity. The Witch-hazel (Plate LXXXII), is a good example of a species whose seeds are scattered by mechanical propulsion. Man has been distributing seeds for forest trees inten- tionally or unintentionally for many centuries, with the result that the forest structure and landscape in many localities have been en- tirely changed. Many European and Asiatic species have been planted in America, and many of our native species like the Common Locust and White Pine have a wide distribution abroad. Wind is the most powerful of the dispersal agents. Many seeds have special structural modifications which adapt them to be scattered by the wind. The modifications may be a sac-like envelope (Plate IX, 10), a mat of straight capillary hairs (Plate IX, 4, 6) or a membranous winged, or flattened seed (Plate IX, 2 and Plate X, 3, 6, 11), Ani- mals also scatter many seeds. A great number are scattered involun- tarily by animals, especially such seeds as will hang fast to their bodies. Other fruits are juicy and edible and are often eaten by birds and other animals. A large number of our common birds swal- low seeds to get the juicy edible portion surrounding them. These seeds are not injured in passing through the alimentary canal of birds, but in some cases it is thought that the seeds are even bene- fited. The robins, thrushes, and blue birds eat a large quantity of fleshy fruit and should be regarded as valuable agents for dispersing seeds. The blue jay is also an agent that helps to scatter heavy seeds like chestnuts and acorns. Other animals, especially rodents, are also valuable as seed dispersal agents. Water, while not so 49 important as wind, must still be regarded as an agent of seed dis- persal. It transports some seeds over great distances, especially those which will float or are inclosed in bladder-like inclosures like the American Hop Hornbeam (Plate IX, 1.0), or the Bladder Nut, a small shrub very commonly found along our streams. Gravity on slopes, is a minor agent of seed dispersal, but sometimes does effective work, especially with heavy seeded species like Oak and Beech. 9. WOOD : Wood, next to food, and clothing, is probably the most useful and indispensable material which man uses. It is found in many of the higher plants but becomes of commercial importance only in the sper- matophytes or seed-bearing plants. In the timber-producing trees it is found in the roots, branches, and stems. The wood derived from the roots is limited in quantity and inferior in quality. The branches produce wood which, in some respects, very closely resembles that of the stem, but is inferior on account of its smaller size, 'irregular shape, and more knotty structure. The wood obtained from the stem is of the greatest utility and value on account of its desirable dimensions and satisfactory structure. The stem should not only yield a large quantity of wood but also a superior quality. The quality of wood which a stem will yield depends largely upon its age, inherent ten- dencies of the species, and its environment during its development. High grade material is usually obtained from the stems of valuable species which have attained a large size, are free from lateral branches, and possess little stem taper. The form and character of the stem are dependent on the environment. A suitable environment may be created by applying the fundamental principles of forestry which will not only increase the productivity of our forests but also the quality of the yield. In order to identify the different kinds of woods it is necessary to study them from the, following three sections: cross, radial, and tangential (Plate XI, 7). An examination of a cross-section of a woody stem will show that the major part of the structure consists of wood which is covered with bark on the outside and has a narrow cylinder of soft tissue known as pith running through the center (Plate XI, 1). The woody portion of most of our trees, especially the older ones, may be differentiated into two parts on the basis of colors. The central colored part is known as the heartwood, while the outer al- most colorless part is known as the sapwood. A narrow zone of cells located between the sapwood and the bark is known as the cambium (Plate XI, 1). All the wood elements have their origin in this zone. For sometime after their origin these elements are living, but later 50 they become functionless and die. The sapwood comprises the peripheral zone of wood which lies next to the cambium and contains the only living elements of the wood. The heartwood comprises all the wood inside of this zone. The elements of the latter are dead and usually dark in color. The line of demarcation between the two regions is usually sharp. The width of the sapwood is variable. In some species like Sassafras it is very narrow, while in other species like Hickory it is wide. The depth of color of the heartwood is also variable. In some species like Persimmon it is very dark in color while in other species like Hemlock there is very little dif- ference in color between the heartwood and sapwood. The cross-section also shows that the wood is divided into numer- ous concentric zones or rings. These are known as annual rings since each one usually represents the growth of a season (Plate XI, 1, 3). Certain disturbances like frost, drought, and insect damage may cause the formation of a second ring in the same season. These rings are known as false or fictitious growth rings. Growth rings have a physiological origin. They represent alternating periods of rest and activity, and occur in practically all trees of the temperate region, characterized by an active vegetative period in summer and a resting period in winter. As one approaches the equator the growth rings disappear, since the seasonal changes are not so sharp. Each growth ring may be divided into two parts, the inner, called early or spring woody and the outer, called late or summer wood (Plate XI, 3). The cross-section further shows radial lines crossing the growth rings at right angles. These are known as medullary or pith rays, or simply as rays. A few of them originate in the pith and extend through the wood into the bark. Such are known as primary rays. As the stem increases in size .additional rays are necessary. These originate in the wood, extend into the bark and are known as sec- ondary rays. The rays are very valuable in distinguishing the wood of many of our common trees since the different woods possess rays which vary in height, width, and structure. The very wide rays of the Oaks enable one to distinguish their wood from that of all other species. These large rays are a valuable asset to Oak wood since they give rise to the beautiful figure which one finds on some oak furniture and interior finishings. The best figure is obtained by quarter-sawing i. e. cutting it radially. The end of a freshly cut log of pine is often covered with small drops of resin, which were given forth from small openings in the wood. These openings are known as resin ducts (Plate XI, 1, 2). They are long intercellular channels bounded by a layer of epithelial cells.. Their presence in the wood of the Pines, Larches, and Spruces enables one to distinguish them from all other trees. Injury may 51 sometimes stimulate the formation of abnormal resin ducts in woods in which they do not occur normally. In some woods elements occur, known as vessels, which facilitate the transportation of water in the stem. Their presence or absence and their structure and distribution are among the most valuable characteristics in classifying woods. On the basis of porosity one may divide the woods into three classes, viz: (1) Ring-porous or Unequal Pored, (2) Diffuse-porous or Equal Pored, and (3) Non- porous. Chestnut and Oak wood are excellent examples of the ring- porous class (Plate XI, 4, 5). A zone of large pores is found in the early wood and smaller pores in the late wood. Maple and Beech are common examples of the diffuse-porous class (Plate XI, 6). The pores of this class are approximately of the same size and distributed uniformly throughout the growth ring. Pine and Hemlock are com- mon examples of the non-porous class in which pores are entirely absent. (Plate XI, 3). The wood of this class is also classified as Homogeneous, while that with pores is classified as Heterogeneous. The various woods possess other characteristics which are valu- able in distinguishing them and in using them in the arts. The wood of the different species varies almost as widely as do their flow- ers, fruits, and leaves, especially with reference to grain, weight, hardness, color, gloss, smell, shrinkage, durability, penetrability, etc. These variable properties and the manifold uses to which the different woods are put are discussed under each species. (52) PART II. MANUAL OF PENNSYLVANIA TREES. The Identification, Tabulation, and Description of Species. (53 ) (54) MANUAL OF PENNSYLVANIA TREES. IDENTIFICATION OP SPECIES. NAMES OF TREES: Trees have two kinds of names, common and scientific. Some species of trees have only one common name while others may have as many as thirty. The same species of tree may have one common name in one locality and an entirely different one in another locality. The Pitch Pine described on page 71 is known in some parts of this State as Jack Pine and in other parts as Nigger Pine. The common name given at the top of each descriptive page is the proper common name and the one used throughout this publication for that particular species. Under the heading "Distinguishing Characteristics," other common names are given. Since Linnaeus published his "Species Plantarum" in 1753, plants have been known by scientific names. These names, as a rule, consist of two parts, the generic and the specific, as is shown by the following species of trees: — Pinus Strobus, Quercus alba, Fraxinus americana, Acer rubrum. The first or generic part refers to the genus and corresponds to a surname. The second or specific part re- fers not to a group of plants but to a particular kind and corre- sponds to the Christian name of a man. The White Pine, Red Pine, and Pitch Pine are different kinds of pines. They belong to the same genus or group and hence have the same generic name, Pinus. Each one, however, is designated by a different specific name. For example, the White Pine is known as Pinus Strobus, the Red Pine as Pinus resinosa, and the Pitch Pine as Pinus rigida. Closely re- lated species are placed in the same genus and closely related genera (plural of genus) in the same family. Such closely related trees as the Pines, Spruces, Firs, and Larches, are placed in the Pine family — Pinaceae. At the time when plants first were studied seriously the Latin language was the one used most commonly to preserve knowledge. The plants consequently were given Latin names. The giving of Latin names to plants and animals has continued down to the present time and no doubt will continue. In the Latin language one finds that plant-names have gender, and that the termination differs (55) 56 in each gender. The specific part of the name must agree in gender with the generic part. The generic name Quercus is feminine, hence the Ked Oak is known as Quercus rubra while the generic name Acer is neuter, hence the Red Maple is known as Acer rubrum. The scientific names used in this publication are those found in the Seventh Edition of Gray's Manual of Botany, and are in keeping with the rules of nomenclature laid down at a Congress in Vienna. On account of the present unsettled condition of our nomenclature it is often possible to find a certain species designated by two or more dif- ferent scientific names, e. g., the Scrub or Bear Oak is known as Quercus ilicifolia, Wang. ; Quercus nana, Sarg. ; or Quercus pumila, Sudw. The authorized scientific name is given at the top of each descriptive page, and where other scientific names are in common use, they are given as synonyms just below the authorized one or in the description. The mere knowledge of the names of trees is of little value or satisfaction. The name is simply a means by which to come nearer to the plant. Learning the names of trees serves about the same purpose as learning the names of persons. It is merely an introduc- tion which allows us, in fact often stimulates us, to become more intimately acquainted with their life-processes, associations, en- vironments, and commercial importance. EXPLANATION OF TERMS AND HEADINGS : Some readers no doubt will find terms in this publication whose meaning they do not know. Some of the terms have been discussed at length in Part I while others will be defined in a glossary follow- ing the description of the species. The description of the species of trees contained in this publication is subdivided into a number of headings. Most of these headings are discussed at length in Part I. The significance and scope of those headings not discussed in Part 1 will follow at this point. Under the several headings is given such descriptive material which will be of value not only to the student of Dendrology but also to the layman who may know little concern- ing the characters and habits of trees. The headings have been so selected and treated that one should be able to identify our com- mon trees at all seasons of the year. Under the heading "Distinguishing Characteristics" ajre given both general and specific characteristics by which the species can be recognized. The species are usually compared with other rather closely related ones with which they might be confused. The dis- tinguishing characteristics and comparisons are based upon the trees native to Pennsylvania, and consequently do not embrace other closely related species found outside of the State. 57 The headings "Range" and "Distribution in Pennsylvania" are often of special importance on account of their identificational value. Many species of trees have a limit to their geographical distribution in this State, and by knowing this accurately one is often able to identify a species 'by the process of elimination. The Sweet Buckeye and Fetid Buckeye are found only in a few counties in the western part of the State. The Ked Pine and Paper Birch are found only in the northern part, while the White Cedar is found only in a few counties in the extreme southeastern part of the State. If one finds a birch tree growing in the forest in the southern part of the State, he can feel certain that it is not Paper Birch, because this is beyond the southern limit of this species. A coniferous tree growing wild on the top of the South Mountains in Franklin county, Pennsylvania, must be a Pine, Hemlock, or Red Cedar, because no other coniferous trees grow there. Further we know that it cannot be the Red Pine, because this species does not extend so far south in the State, and on the basis of habitat we can also be reasonably sure that it is not the Yellow Pine, the Jersey or Scrub Pine, nor the Hemlock, bedause they very seldom ascend to the tops of the mountains, but usually re- main at lower elevations. Likewise, if a maple tree is found at the same place we know that it is the Red Maple or Mountain Maple because they are the only Maples found in that particular locality. If Magnolia trees are found in Centre county one can be certain that the species is not Laurel Magnolia, (Magnolia virginiana), because this species has its western limit of geographical distribution at Caledonia, near Chambersburg, Franklin county. The habitat also aids considerably in identifying various species. A birch tree found growing upon a mountain slope or mountain top is rarely the River Birch, because the latter usually frequents moist locations like banks of streams and lakes. Chemical composition of the soil also influences distribution. A soil rich in lime seldom has Chestnut growing upon it, at least in stands, while other species seem to thrive upon such soil. No doubt at least 99% of the Cumberland Valley in this State was originally timbered with a heavy forest, but very little of it was Chestnut, while on the adjoining mountain slopes of both the South and North Mountains, Chestnut is the prevailing species. Just as the Chestnut is essentially a tree of the slopes so the White Oak is essentially one of the bottom lands, and Table Mountain Pine of the mountain tops. The heading "Importance of the Species" was introduced simply to give general information concerning the forestal significance of the species and their adaptability for ornamental purposes. This heading is especially important when we realize that of the more than one hundred and twenty-five species of trees found in this State, 58 fewer than twenty-five are important for timber-producing purposes. Many inferior species which have little present or prospective value have been introduced into this publication, since it was thought just as important to know what not to plant as to know what to plant. Some species may not be valuable for the production of timber but they may have a value as shelter to other species or as soil pro- tectors and soil conservers. Many species which cannot be regarded as final members of a timber-producing forest may be of temporary value in helping to establish the more valuable permanent species. We should be cautious in eliminating the inferior species from our ^ forest structure, because they may possess a value which is not evi- dent at the present time. It should be remembered that the species despised by myself may be .prized by my neighbor, and that the -species despised today by my neighbor and myself may be prized by both of us tomorrow. Only general statements are made with reference to the importance of the species. A fuller discussion of this heading may be found in any standard text on General Forestry or Silviculture. How TO IDENTIFY THE SPECIES AND USE THE KEYS: Since this publication is intended primarily for laymen and for students who are just beginning the study of trees, the omission of technical terms was thought advisable. We have many species of trees, some common, others uncommon, which the average layman may not know. He can learn them readily if their distinguishing characteristics are presented to him in ordinary language accom- panied by simple and exact drawings. This publication is designed so that the average layman with even a limited knowledge concern- ing trees can use it and identify the various species with little, if any, difficulty. The procedure or method of identification varies with the indi- vidual. One may take material from a tree and compare it with the drawings until he finds one with which it corresponds or to which it fits, and then feel satisfied that he has learned to know the tree. To check himself and to acquire additional information he may read over the descriptive material accompanying each plate. This method of comparison with plates, while the one commonly used by laymen who have little or no working knowledge concerning trees, is labor- ious and entirely unscientific. A better and yet simple method is the use of an analytic key for the identification of the species. Such keys according to their construction may be simple or complex, service- able or unserviceable to the average layman. In constructing the subjoined analytic key, an attempt was made to make it simple and yet exact, based upon permanent rather than transient, and constant 59 rather than variable characteristics. This publication will no doubt come into the hands of different classes of people, some of whom will recognize at a glance the genus to which a certain tree belongs, while others will not have the slightest idea as to what it is. An attempt has been made to satisfy both types of persons. The former can go at once to that portion of the publication where the genus under consideration is treated and by the use of the "Key to the Spec- ies" determine the exact species which they have at hand, while the latter should begin at the "Key to the Families" found on page 63, and use the key until the family to which it belongs is found, then go to the family and use the "Key to the Genera" and the "Key 'to the Species" until the species is determined. With a little practice one will find it easy to use such simple keys. Before attempting to use a key, it is necessary that good material be available. Parts of trees vary considerably, depending upon the environments in which they were developed. An abnormal environ- ment will produce abnormal organs, and if these should be the parts with which you are attempting to identify the species through the use of the keys, it is natural that it would be a difficult task. Struc- tural variations are commonly found in leaves, flowers, fruit, bark, as well as other plant organs. Upon the same tree or even the same branch one may find three or more distinct varieties of leaves. On account of this variation, which often makes identification difficult, abundant material should always be at hand, and especially that which is normal in appearance. The keys are based upon normal ma- terial and may not fit variable forms. Only by years of constant and careful study of trees will one be able to distinguish accurately be- tween normal and abnormal material ; but by carefully observing and constantly studying the trees one will unconsciously absorb many de- tails concerning them which can be appreciated but not described. This unconscious absorption of appreciable but indescribable detail in trees has a greater significance than we attribute to it at first. The writer, in conducting field work (Fig. 7) for five years in connec- tion with a course in Dendrology given at the Pennsylvania State Forest Academy, finds that the students learn to notice many differ- ences between species, which differences they cannot describe. The keys are subdivided into three classes, viz: "Key to the Fam- ilies," "Key to the Genera" and "Key to the Species." The "Key to the Families" is found on page 63, preceding the description of any of the species. The "Key to the Genera" is found under the descrip- tion of each family which contains more than one genus; and the "Key to the Species" is found under such genera which contain more than one species. The reason for subdividing the keys into three classes instead of combining all three into a general key to genera 60 and species, was the fact that a combined key is often difficult to use on account of its great length, and tedious to operate for those who can recognize the family or genus at a glance but do not know the species. Besides, keys to the genera and keys to the species are more serviceable w'hen placed close to the written description and its ac- companying plate than if they precede the descriptive material of all the species. The three classes of keys are constructed on the same plan; conse- quently, they can be used in the same manner. To use them it is necessary to make a 'choice for the most part between two alternatives stated in two paragraphs preceded by the same number. The choice leads to another number or to a family, a genus or a species followed by the page upon which a further description is found. The Sugar Maple may be taken as an example to show how to use the key. Un- der "Key to the Families," page 63, we start with 1. We have the choice between trees with "Leaves narrow, needle-like, awl-like, or scale-like, usually persistent except in the genus Larix" and trees with "Leaves broad, flat, rarely five times as long as wide, usually deciduous." We select the latter, which is followed by 2. Under 2 we have the choice between "Leaves opposite or whorled, i. e. 2 or 3 occur at a node'' and "Leaves alternate, i. e. only one occurs at a node." We choose the former, which is followed by 3. Here we have the choice between "Leaves or at least most of them three at a node" and "Leaves always two at a node." We select the latter, which is followed by 4. Here we have the choice "Leaves simple" and "Leaves compound." We select the former, which is followed by 5. Here we have the choice between "Leaves palmately lobed" and "Leaves not lobed." We select the former, which is followed by Aceraceae, which is the family name for the Maples. This is followed by a number which indicates the page upon which a further descrip- tion of the family may be found. At this point it is advisable to check one's self. This can be done by carefully studying the descrip- tive matter of the family indicated in order to find out if the de- scription corresponds to the species under consideration. If the description does not correspond it is advisable to go back to the "Key to the Families" and attempt to find the mistake. If the de- scription does correspond it is reasonable to think that the "Key to the Families" was used correctly. If you feel certain that this is the correct family you should go to the "Key to the Genera," or to the "Key to the Species." No "Key to the Genera" is given under this family because it contains only one genus. Under the "Key to the Genera" and the "Key to the Species" the same method of procedure should be used that was used under the "Key to the Families." On account of the wide variation between the distinguishing characteris- 61 tics which are present in summer from those which are present in winter, it has sometimes been found necessary to make two keys to the species, one a summer key and the other a winter key. Two such keys are found under the Maple family. If the material at hand hap- pens to be a spray of leaves of the Sugar Maple, the summer key should be used, and if it happens to be a branchlet with buds, the winter key should be used. Since the family key which was used to this point was based pri- marily upon summer characteristics, the winter key will now be used in order to familiarize you with the slight variations which are found between the two keys. Under "Winter Key to the Species," page 191, we start with 1. Under 1 we have the choice between "Buds stalked with few exposed scales" and "Buds sessile or nearly so, with 6 or more exposed scales." We select the latter, which is followed by 4. Un- der 4 we have the choice between "Buds with 8-16 exposed scales, brown, acute, non-collateral; leaf-scars nearly encircle stem" and "Buds with 6-8 exposed scales, red or green, obtuse." We select the former which is followed by Sugar Maple (Acer saccharum) page 194. On this page a full description of the species js found accompanied by a sketch on the opposite page of the principal characteristics. If the descriptive material and the sketches show that this is the species under consideration, one may feel satisfied that the key has been used properly. If the description does not correspond it is advisable to go back to the beginning of the key, follow the same pro- cedure indicated above but eliminating the mistake which must have been made. The same method of identification or procedure should be used for every other species. In a short time one will be familiar enough with the use of the key to identify the species and will do so with considerable accuracy. If you cannot identify the specimen at hand with the aid of the keys, description, and plates, there are still other means which you may use: It may be possible that an institution or a private person in your part of the State possesses an herbarium in which may be found a similar specimen properly labeled. If you can get access to such an herbarium and find that your specimen and the one in the herbarium are alike, and that the herbarium specimen was labeled by a reliable person, it is reasonable to assume that you have identi- fied your specimen correctly. It may also be possible that some one connected with some local educational institution will be able to as- sist you in identifying the material. All material sent to the Den- drological Department of the Pennsylvania State Forest Academy, Mont Alto, Pa., will be identified free of charge. Persons sending material should always aim to send an abundance of it. If flow- ers, leaves, fruits, and bark are obtainable they should all be sent. 62 The wider the range of material the easier and the more accurate the. identification will be. Those who desire to collect and preserve material should proceed in the same manner as one would in making general botanical col- lections. The dried material may be secured on strong mounting paper. The writer has found the "Biker Specimen Mounts" very satisfactory for preserving and displaying the different parts of trees. Different sizes are obtainable, which allows one to select them in proportion to the size of the material to be preserved. 63 GENERAL KEY TO THE FAMILIES. Page. 1. Leaves narrow, needle-like, awl- like, or scale-like, usually persistent except in the genus Larix, Pinaceae 67 1. Leaves broad, flat, rarely five times as long as wide, usually deciduous, 2 2. Leaves opposite or whorled, i. e., two or three occur at a node, 3 2. Leaves alternate, i. e.f only one occurs at a node, 10 3. Leaves, or at least most of them, three at a node Bignoniaceae 211 3. Leaves always two at a node 4 4. Leaves simple 5 4. Leaves compound 8 5. Leaves palmately lobed, Aceraceae 190 5. Leaves not lobed, 6 6. Leaves serrate, Viburnum in Caprifoliaceae 218 6. Leaves entire, 7 7. Leaves 3-6 inches long with curving parallel veins; bases of leaf stalks enlarged, encircling twigs, Cornus in Gornaceae 204 7. Leaves 4-8 inches long without curving parallel veins; bases of leaf stalks do not en- circle twigs Chionanthus in Oleaceae 217 8. Leaves palmately compound Sapindaceae 200 8. Leaves pinnately compound, 9 9. Leaflets usually 5-11; finely toothed or entire margined, Fraxinus in Oleaceae 212 9. Leaflets usually 3, sometimes 5-lobed or coarsely serrate, ..Acer Negundo in Aceraceae 197 10. Leaves simple, 11 10. Leaves compound, 40 11. Leaves persistent 12 11. Leaves deciduous 14 12. Leaves not armed with spiny teeth, 13 12. Leaves armed with spiny teeth, Ilex opaca in Aquifoliaceae 188 13. Small trees; leaves stout, white silky beneath, not taper pointed; flowers soli- tary, ..' Magnolia virginiana in Magnoliaceae 156 13. Shrubs; leaves leathery, yellowish-green to scurfy beneath, often taper pointed; flowers in clusters, Rhododendron and Kalmia in Ericaceae 207 14. Leaves with entire margins, 15 14. Leaves with toothed, lobed, or incised margins, 23 15. Leaves broadly heart-shaped; flowers reddish-purple, shaped like pea blossoms; fruit a pea-like pod, Cercis in Leguminosae 180 15. Leaves not broadly heart-shaped; flowers not shaped like pea blossoms; fruit not a pea-like pod, 16 16. Stout axillary spines present; fruit 3-5 inches in diameter, Maclura in Urticaceae 153 16. Stout axillary spines absent; fruit smaller 17 17, Leaves decidedly aromatic, often somewhat lobed; twigs spicy-aromatic, mucilagin- ous if chewed Lauraceae 161 17. Leaves not aromatic or lobed; twigs not spicy-aromatic, nor mucilaginous, 18 18. Leaves 2-G inches long; flowers small except pistillate of Diospyros, not soli- tary, 19 18. Leaves more than 6 inches long; flowers large and solitary 22 19. Leaves bristle-tipped, linear-lanceolate to oblong; pith star-shaped; fruit an acorn.... Quercus imbricaria and Q. phellos in Fagaceae 146 19. Leaves oval-ovate or obovate, not bristle-tipped; pith not star-shaped; fruit a drupe or a berry, 20 64 Page. 20. Leaves thin, clustered at tip of twigs, with prominent curved parallel veins; small trees; twigs greenish streaked with white, Cornus alternifolia in Cornaceae 205 20. Leaves thick, not clustered at the tip of twigs; veins not parallel; medium sized trees; twigs not greenish 21 21. Leaves 4-6 Inches long; leaf petioles with one fibro- vascular bundle; fruit a globular berry 1-1J inches in diameter, , Ebenaceae 210 21. Leaves 2-5 Inches long; leaf petioles with 3 fibro- vascular bundles; fruit a purple ovoid drupe | of an inch long, ". Nyssa in Cornaceae 206 22. Stipules and stipule-scars encircle twigs; flowers greenish-white or yellowish; fruit cone-like; twigs often aromatic and bitter Magnoliaceae 155 22. Stipules absent; flowers reddish-purple, ill-smelling; fruit banana-like, edible; twigs not aromatic or bitter Anonaceae 160 23. Leaf margins usually lobed or incised 24 23. Leaf margins usually toothed 29 24. Leaves star-shaped Liquidambar in Hamamelidaceae 163 24. Leaves not star-shaped, 25 25. Leaves silvery beneath Populus alba in Salicaceae 94 25. Leaves not silvery beneath, 26 26. Leaves rough on upper surface, with milky juice, Morus in TJrticaceae 154 26. Leaves not rough on upper surface, without milky juice 27 27. Leaves decidedly aromatic, lobed or entire; twigs spicy-aromatic, mucilaginous, Lauraceae 161 27. Leaves not aromatic; twigs not spicy -aromatic nor mucilaginous, 28 28. Leaves palmately veined; base of leaf petioles hollow; leaf lobes irregularly toothed. Platanaceae 175 28. Leaves pinnately veined; base of leaf petioles not hollow; leaf lobes rounded or bristle-pointed, intervening spaces deep or shallow, Most species in Fagaceae 124 29. Leaves with an oblique base 30 29. Leaves uot with an oblique base, 32 30. Leaves ovate or ovate-oblong; rough on upper surface, TJlmus and Celtis in TTrticaceae 148 30. Leaves rounded, heart-shaped, or obovate; smooth on upper surface, 31 31. Leaves straight-veined with wavy margins; flowers in late autumn; fruit without bract. Hamamclis in Hamamelidaceae 162 31. Leaves not straight veined, deeply and sharply toothed; flowers appear in summer; fruit with bract, Tiliaceae 202 32. Leaves dentate or coarsely toothed, t 33 32. Leaves not dentate nor coarsely toothed 34 33. Leaves with laterally flattened petioles, Populus grandidentata in Salicaceae 97 33. Leaves not with laterally flattened petioles Few species in Fagaceae 124 34. Fruit dry 35 34. Fruit fleshy 37 35. Leaves decidedly sour; flowers and fruit produced in racemes resembling the lily of the valley Oxydendrum in Ericaceae 209 35. Leaves not sour; flowers and fruit not produced in racemes, 36 36. Fruit 1-seeded, nut or samara, subtended by bracts; seeds without tuft of hairs at apex; flowers monoecious; calyx present Bctulaccae 111 36. Fruit a small capsule inclosing numerous seeds; seeds with tuft of hairs at apex; flowers dioecious; calyx absent, Salicaceae 88 37. Thorns or spine-like spurs present, Prunus americana, Pyrus coronaria, and Crataegus sp. in Rosaceae 164 37. Thorns or spine-like spurs not present 38 38. Fruit with a single stone Prunus in Rosaceae 165 38. Fruit several-seeded, 39 39. Leaves heart-shaped or rounded at base, 3-4 inches long; floAvers in loose racemes, Amelanchier in Rosaceae 174 39. Leaves wedge-shaped or rounded at the base, 4-5 inches long; flowers solitary or in one to few flowered axillary clusters, Ilex monticola in Aquifoliaceae 189 40. Leaves with entire margins, 41 40. Leaves with toothed margins 44 41. Leaves even-pinnate, Gleditsia and Gymnocladus in Leguminosae 41. Leaves odd-pinnate, 42 Page. 177 42. Leaflets small, elliptic; twigs thorny, . 42. Leaflets large, ovate; twigs not thorny, Robinia in Leg-uminosae 43 181 43. Leaflets 7-21, not toothed at base, without glands, Rhus Vernix and R. copallina in Anacardiaceae 183 43. Leaflets 11-41, sometimes with 2-4 blunt teeth at base which have glands on lower side at the point of each tooth, Simarubaceae 187 44. Twigs and leaves prickly; leaves twice or thrice compound Araliaceae 199 44. Twigs and leaves not prickly; leaves once compound 45 45. Large trees; staminate flowers in aments; fruit a nut, Juglandaceae 45. Small trees; staminate flowers not in aments; fruit red and fleshy, 46 100 46. Leaflets 13-15; sap not milky; branches heavy-tipped, Pyrus americana in Rosaceae 173 46. Leaflets 11-31; sap milky; branches heavy-tipped, Rhus typhina and R. glabra in Anacardiaceae 183 TABULATION OP GENERA AND SPECIES. Families, Genera, etc. Species. World. td Pennsylvania. • s . A winged seed, natural size. 6. A seed, enlarged. 7. Terminal portion of a twig with buds and without needles, enlarged. 8. A seedling, natural size. 81 BLACK SPRUCE. Picea mariana, (Miller) BSP. FOEM — A small tree usually attaining a height of 20-30 ft. with a diameter of 1 ft., but may reach a height of 100 ft. with a diameter of 3 ft. Trunk straight, continuous, very taper- ing, bearing irregular, rather short, horizontal branches, often with ascending tips which give the tree a very narrow, irregular, conic form. BARK — Up to * of an inch in thickness and roughened by irregular, thin, close, grayish- brown scales. See Fig. 51. TWIGS — Rough, stout, brown to yellowish-brown, covered with pale to black hairs. BUDS — Ovoid, sharp-pointed, i-J of an inch long, covered with overlapping, sharp-pointed, reddish-brown scales. LEAVES — About £-2 of an inch long, 4-sided, bluish-green, rounded at apex, straight or slightly curved, without real leaf-bases, but resting on decurreut projections of bark known as sterigmata. LEAF-SCARS — See "Leaf-Scars" under Red Spruce. FLOWERS — Appear about May. Staminate and pistillate flowers occur on same plant but often on different parts of it. Staminate sub-globose, almost sessile, i of an inch long, reddish in color. Pistillate oblong, cylindrical, & of an inch long. , FRUIT — A cone about li inches long, short-ovoid, short-stalked, maturing at the end of the first season; core-scales rounded, dull grayish-brown with jagged margin. WOOD — Non-porous; with resin passages present; light, soft, not strong, pale yellowish- white in color. Weighs 32.86 Ibs. per cubic foot. Used in the manufacture of paper pulp and occasionally in lumber. DISTINGUISHING CHARACTERISTICS — See "Distinguishing Characteristics" under Red Spruce page 80. RANGE — It is a transcontinental species extending from Labrador to Alaska and south to Pennsylvania and Wisconsin. DISTRIBUTION IN PENNSYLVANIA — Frequents swamps, rather common along lakes and in swamps of Monroe and Pike counties and in Bear Meadows, Centre and Huntingdon counties. Also reported in Cambria, Clinton, Lackawanna, Lycoming and Mifflin counties. HABITAT — The Black Spruce, also known as Swamp Spruce, usually frequents cold, poorly drained swamps throughout its range. It sometimes ascends well drained hillsides, but is usually stunted in such situations. It makes its best growth on moist alluvial soils and is very tolerant of shade. IMPORTANCE OF THE SPECIES — The Black Spruce is of little commercial importance in Pennsylvania and should be considered for forestry purposes in extremely swampy locations only, where other more valuable species will not grow. It cannot be recommended for orna- mental planting since other species of Spruce far surpass it for this purpose. 82 NORWAY SPRUCE. Picea Abies, (Linnaeus) Karsten. FORM — A large tree usually attaining a height 01' 50-80 ft. with a diameter of 2 ft., but may reach a height of 125 ft. with a diameter of 3 ft. Trunk straight, continuous, slightly tapering, and sometimes free from lateral branches for a considerable distance from the base. Crown less acutely pyramidal than that of our native species. BARK — On old trunks roughened with large, rather thick reddish-brown scales; on younger trunks the scales are thinner and closer. Used in tanneries in Europe, but only slightly charged with tannin. TWIGS — Slender, rather pendulous, light reddish-brown and roughened by projecting leaf- BUDS — Ovate to conical, smooth, pointed, covered by overlapping, sharp-pointed, light brown scales. LEAVES — About J-l inch long, sharp-pointed, 4-sided, dark green, without real leaf-stalks, but resting on decurrent projections of bark known as sterigmata. LEAF-SCARS — See "Leaf -Scars" under Red Spruce. FLOWERS — Appear about May when pollination takes place. Fertilization takes place in June. FRUIT — A cone about. 4-7 inches long, cylindrical-oblong, pendant, almost sessile, maturing at the end of the first season; cone-scales thin, stiff, rather broad reddish-brown with finely toothed margin. WOOD — Non-porous; resin passages present; straight-grained, strong, not durable In con- tact with the soil, medium in hardness, works easily, heartwood yellowish-white with thin white sapwood. Weighs 30 Ibs. per cubic foot. Used in the manufacture of paper pulp, general construction, interior finish, basket making and for masts and oars on small vessels. DISTINGUISHING CHARACTERISTICS — The Norway Spruce, also known as the European Spruce, can readily be distinguished by its large cones, which are from 4-7 inches long, and by the long, pendulous branchlets terminating the lateral branches. The sharp-pointed, bluish- green, 4-sided needles will also aid in distinguishing it from some of the other closely related species. RANGE — Its native home is in middle and northern Europe. It forms a very important part of the forest structure of Germany, Switzerland, Austria and Russia. Planted extensively in the United States for ornamental purposes from Maine south to Washington and west to Kansas. DISTRIBUTION IN PENNSYLVANIA— It is found throughout the State as an ornamental tree, and planted rather extensively for forestry purposes by the State Department of Forestry. HABITAT — In Europe it grows in valleys and upon the mountain slopes. It prefers rather rich moist soils, in this respect somewhat resembling the White Pine. It cannot endure very dry, very sterile, or extremely rich vegetable soil. It is rather tolerant of shade and some- what susceptible to late frosts. IMPORTANCE OF THE SPECIES — The Norway Spruce is a foreigner in our forest flora, but before long it will be regarded a naturalized member of our forest structure. It will be an extremely valuable addition to the list of species of forestal significance. To the present time it has been planted mostly for ornamental purposes and for wind breaks, but in the future it will also b« planted extensively as a forest tree. It grows rapidly and is rather hardy and free from organic enemies and produces valuable wood. A noted European authority on forestry has said: "Spruce is the best paying forest species in the world." It should be planted as a seedling and preferably mixed with such species as White Pine, European Larch, Douglas Fir, Red Oak, White Ash, and Tulip Tree. It is also possible that it could be grown at a profit for Christmas tree purposes. PLATE XXII. NORWAY SPRUCE. 1. Branch with staminate flowers, x i. 2. Branch with pistillate flowers, x J. 3. A needle, natural size. 4. Cross section of a needle, enlarged. 5. Branch with needles removed showing winter buds, x 1. 6. Branch with needles and a cone, x |. 7. A cone scale with two winged seeds, natural size. 8. A winged seed, enlarged. 9. A seed, enlarged. 1Q. A seedling shedding a seed coat, natural size. 11. A seedling, natural size. PLATE XXIII. HEMLOCK. 1. Branch with needles and staminate flowers, x J. 2. Branch with needles and pistillate flowers, x 5. 3. Branch with needles and mature cones, x J. 4. A cone scale with two winged seeds, natural size. 5. A winged seed, natural size. 6. A seed, enlarged. 7. Leafless branch with buds, enlarged. 8. A seedling, natural size. S3 HEMLOCK. Tsuga canadensis, (Linnaeus) Carriere. GENUS DESCRIPTION — This genus comprises 8 species in the world, 4 of which are native to North America and 1 to Pennsylvania. Of the 4 species native to North America, 2 are found in the eastern and 2 in the western part. The 2 eastern species are the Carolina Hem- lock (Tsuga caroliniana Engelm.) found only in the mountains from Virginia to Georgia, and the species described below. The Hemlocks are trees of the northern hemisphere, found in North America and Asia, but absent in Europe. The eastern species in particular are slow growers and difficult to transplant. A well known student of forestry has said, "Hemlock trees are like the Indians, they will not stand civilization." FORM — A large tree usually attaining a height of 60-80 ft. with a diameter of 2-3 ft., but may reach a height of 100 ft. with a diameter of 4 ft. In the open its crown is dense, conic, and high with limbs extending almost to the ground. In dense stands it has a bole, clean from lateral branches for a considerable distance from the ground and with little taper. BARK — Grayish-brown to reddish-brown, rich in tannin, becoming 4/5 of an inch thick on old trunks and roughened by long fissures separating rather broad ridges which are covered with close scales. Innner bark is cinnamon-red. See Fig. 53. TWIGS — Slender, rough on account of decurrent projections of bark upon which the leaves rest, at first somewhat hairy and yellowish-brown, later smooth grayish-brown tinged with purple. BUDS — Alternate, ovate, 1/16 of an inch long, blunt-pointed, reddish-brown, not glossy. LEAVES — Linear, flat, about J of an inch long, rounded or notched at apex, dark green and shining above, pale green and dull below with a white line on each side of midrib. The leaves persist for about 3 years and are jointed to short, persistent, woody stalks. They are some- what spirally arranged around the twig but appear two-ranked. LEAF-SCARS — Small, round, raised on decurrent projections of bark. FLOWERS — Appear about April or May. Staminate and pistillate flowers separate, but usually borne on the same branch. Staminate small, globose, yellow, about i of an inch long. Pistillate oblong and pale green. FRUIT — A small, short-stalked cone maturing at the end of the first season, about 1 of an inch long, usually persisting during first winter. WOOD — Non-porous; without resin passages; light, hard, not strong, brittle, coarse-grained not durable, liable to splinter, difficult to work, light brown with lighter sapwood. Weighs 26.42 Ibs. per cubic foot. Used for construction, coarse lumber, and especially for frame work and weather-boarding of buildings, paper pulp, and laths. DISTINGUISHING CHARACTERISTICS— The Hemlock, also known as Hemlock Spruce and Spruce Pine, can be distinguished by its flat linear needles with two longitudinal white streaks on the lower surface; the needles are jointed to short persistent woody stalks known as sterig- mata and appoar two-ranked, but in addition to the two conspicuous lateral rows there is a rather inconspicuous row of small needles on top of the twig extending in the same direction as the twig. The lateral twigs occur rather irregularly along the main branches and diverge from the latter at an angle of usually less than 75°. The cones are about 1 of an inch long, and often persist through one winter. The inner bark is cinnamon-red. RANGE — Nova Scotia south to Pennsylvania and along the mountains to Alabama, and west to Minnesota. DISTRIBUTION IN PENNSYLVANIA— Rather commonly distributed in moist situations through- out the mountainous regions of the State. Most common in the central and northern parts. Scattered in local groups in the southeastern and southwestern parts. HABITAT — Usually found in moist locations like northern slopes of rocky ridges, banks of streams, ponds and lakes, swamps, river gorges, and mountain slopes. It prefers a dense forest structure since it is shade loving and not very wind-firm. IMPORTANCE OF THE SPECIES — This tree yields not only lumber but also bark rich in tannic acid and a volatile oil to which a medicinal value was attached. The inferior wood which it produces coupled with its slow growth and the difficulty with which it is established by planting will tend to decrease its prevalence in our forest structure, especially since more valu- able and more rapid growing species like Pine and Spruce will thrive on the same area. Wher- ever it can be regenerated naturally without sacrificing more valuable species it should be retained in the forest structure. It is one of the most attractive if not the most attractive of our conifer- ous evergreens. 84 BALSAM FIR. Abies balsamea, (Linnaeus) Miller. GENUS DESCRIPTION — The Firs comprise about 25 species, of which number 10 species are native to North America and 1 to Pennsylvania. They are usually found in cold and temperate regions. Eight species are found in western North America, while only 2 species are native east of the foot hills of the Rocky Mountains, 1 of which is native to Pennsylvania. The other eastern species not native to Pennsylvania, Abies Fraseri (Pursh.) Poir, is found only in the Appalachian Mountains from Virginia to North Carolina and Tennessee. FORM — A medium-sized tree attaining a height of 30-50 ft., but may reach a height of 100 ft. with a diameter of 3 ft. Usually a low spreading shrub in high altitudes and high latitudes. Crown slender, symmetrical when young, and sharp-pointed, deeper and often broader in older specimens. BARK — On old trees reddish-brown and somewhat roughened by irregular scales. On young trees smooth, thin, close, grayish-brown, and marked by projecting resin blisters. See Fig. 50. TWIGS — Slender, at first hairy and yellowish-green, later smooth, and grayish-brown, usually arranged opposite one another. BUDS — Clustered at end of terminal twigs, ovate to spherical, about 1/6 of an inch long, covered with very glossy, varnished, orange-green scales. LEAVES — Apparently 2-ranked as in the Hemlock, linear, flattened, I of an inch long, usually blunt at apex, stalkless, dark green and shining above, pale with light dots below, very fragrant upon drying. FLOWERS— Appear about May or June. Staminate and pistillate flowers separate but usually found on different parts of same branch. Staminate cylindrical, yellow, \ of an inch long. Pis- tillate oblong-cylindrical, purple, 1 inch long. FRUIT — An erect, oblong-cylindrical, dark purple cone, 2-4 inches long, with broad round deciduous scales which fall off and leave the bare central axis. Cones mature at the end of first season. Seeds about 1 of an inch long, winged, and borne on cone:scales. WOOD — Non-porous; without resin passages; with no distinct heartwood, light, soft, pale brown, not strong noi- durable. Weighs 23.80 Ibs. per cubic foot. Used with Spruce for paper pulp, crates, packing boxes, and occassionally for lumber. DISTINGUISHING CHARACTERISTICS— The Balsam Fir, also known as Fir, Balsam, and Blister Pine, is distinguished from the other native conifers of Pennsylvania by its smooth gray- ish-brown bark covered with projecting blisters, its oblong-cylindrical erect cones with deciduous scales, and by its rather flattened, apparently 2-ranked leaves which are stalkless and leave a circular flat scar upon falling. The leaves of the Balsam Fir somewhat resemble those of the Hemlock, but they are not jointed to a woody stalk while those of the latter species are jointed to short persistent stalks known as sterigmata. RANGE — Labrador west to Alberta, south to Pennsylvania and Minnesota and along the moun- tains to Virginia. DISTRIBUTION IN PENNSYLVANIA— Confined almost entirely to the swamps and lake re- gions of Centre, Pike, Monroe, Lycoming, Tioga, and Sullivan counties. It is also reported from a few other local outposts. HABITAT — Usually inhabits swamps or their borders. In the north found commonly in low swampy bogs but in the south usually found on the mountain tops and slopes. Generally occurs in mixture but may occur locally in almost pure stands. Spruce and Hemlock are its common associates. IMPORTANCE OF THE SPECIES— This tree is of little commercial importance in this State on account of its limited distribution and the small size which it attains. It is difficult to re- generate artificially since the seeds have a low germinating percentage, and the subsequent estab- lishment is also difficult. This species should be regenerated naturally upon such areas where other more valuable species will not grow. The Balsam Fir is commonly used as a Christmas tree and it is possible that in the future it may pay to raise it for this purpose. PLATE XXIV. BALSAM FIR. 1. Branch with needles and staruinate flowers, x J. 2. Branch with needles and pistillate flowers, x J. 3. Branch with needles, three cones and one cone axis from which the scales have fallen, x J. 4. A cone scale with two winged seeds, natural size. 5. A winged seed, slightly enlarged, 6. A seed, enlarged. 7. Leafless brand, with buds, slightly enlarged. 8. A seedling, x 5. PLATE XXV. WHITE CEDAR. 1. A flowering branch, x J. 2. A branch with needles and fruit, 3. A cone, slightly enlarged. 4. A winged seed, slightly enlarged. 5. A seedling, natural size. 6. Portion of branch, enlarged. x i. 85 WHITE CEDAR. Chamaecyparis thyoides, (Linnaeus) BSP. GENUS DESCRIPTION — This genus comprises about 6 species In the world, of which number 3 are native to North America. Of the 3 species native to North America 2 are found in the western part, while only 1 is found in the eastern part. The latter is native to a small portion of Penn- sylvania. The Cedars are not very well known as forest trees, but are planted extensively in this country and abroad for ornamental purposes. The lumberman is just beginning to appreciate the value of the wood which is obtained from the western species. FORM — A small tree usually attaining a height of 30-50 ft. with a diameter of 1-2 ft., but may reach a height of 90 ft. with a diameter of 4 ft Trunk straight, continuous, tapering, and bears slender horizontally spreading branches which form a narrow, pointed, conical crown. BARK — Rather thin, reddish-brown, somewhat furrowed, peels off into long, fibrous, film-like scales. TWIGS — Rather slender, somewhat flattened, at first bluish-green, later after the leaves have fallen they become roundish and reddish-brown. The terminal twigs are often arranged in fan- like clusters. BUDS — Very small and inconspicuous, usually covered by the closely overlapping scale-like leaves. LEAVES — Small, ovate, sharp-pointed, bluish-green, closely overlapping, scale-like, 4-ranked but presenting a compressed appearance. Often spreading and awl-shaped on vigorous shoots. A conspicuous but rather small glandular dot is often found on the back. LEAF-SCARS — Not present because leaves persist for 4 or more years; then die and dry up upon the branches. FLOWERS — Appear in March or April. Staminate flowers oblong, about J of an inch long, with 10-12 stamens on shield-shaped filaments. Pistillate flowers globular, about 1/10 of an inch in diameter, with about six shield-shaped scales each usually bearing 2 ovules. FRUIT — A small globose cone which is rather common but inconspicuous, about I of an inch in diameter and maturing at the end of the first season. Scales of cone shield-shaped and joined to axis of cone by stalk. Outer face of scale is marked by a slight projection. Each fertile scale bears 1 or 2 fertile winged seeds. WOOD — Non-porous; light, soft, not strong, very durable, slightly fragrant, light brown tinged with red; sapwood pale. Weighs 20.70 Ibs. per cubic foot. Used in cooperage and boat building, for fence posts, railroad ties, shingles, and woodenware. DISTINGUISHING CHARACTERISTICS— The White Cedar, also known as Cedar and Coast White Cedar, can be distinguished by its characteristic globose fruit with shield-shaped scales which are fastened to the main axis by means of short stalks. It somewhat resembles the Arbor Vitae but the former has less flattened and less distinctly fan-shaped twigs. The twigs of the White Cedar are not so stout as those of the Arbor Vitae. The former also has bluish-green leaves while the latter has yellowish-green. It can be distinguished from the Red Cedar and the Common Juniper by its more prominent glandular dots on the leaves and its round twigs; the twigs of the latter species are 3 to 4-sided. It also lacks the awl-shaped leaves found on the Common Juniper and usually found on the Red Cedar. RANGE — Cape Breton Island southward along coast region to Florida and Mississippi. DISTRIBUTION IN PENNSYLVANIA — Native only to a few counties in the southeastern part of the State, but found as an ornamental tree in practically every part of the State. HABITAT — Prefers swamps and marshes but will grow in dry locations. Occupies many swamps to the exclusion of other tree species. In the south it is often found in the Swamps with the Bald Cypress and in the north with Arbor Vitae, Fir, and Spruce. IMPORTANCE OF THE SPECIES— This species is so limited in its distribution in Pennsylvania find the wood of so little commercial importance that it cannot be recommended for forestry pur- poses. It may be recommended for very swampy locations where other more valuable species will not grow, and deserves to be planted extensively for ornamental purposes since it is one of the most beautiful coniferous trees of eastern North America on account of its attractive form and beautiful foliage. More than a dozen varieties of it are known. 86 ARBOR VITAE. Thuja occidentalis, Linnaeus. GENUS DESCRIPTION — This genus comprises 4 known species In the world, of which number 2 are found in North America. One of the 2 species native to North America is found in the eastern part, and the other in the western part. The speci«s found in the western part attains a large size, while the one found in the eastern part usually remains a small tree. They are best known as ornamental trees but furnish some lumber, which is very valuable on account of its great durability. The bark also yields tanning material and the twigs and leaves contain a volatile oil which possesses stimulating properties. FORM — A medium-sized tree usually attaining a height of 20-50 ft. with a diameter of 1-2 ft. but may reach a height of 75 ft. with a diameter of 3-4 ft. TRUNK — Tapering, furrowed, buttressed and often divided. Crown dense, conical, very high, and often covered with foliage almost to the base. BARE — Grayish to reddish-brown, thin, furrowed, separating into long rather thin, fibrous and often persistent strips. TWIGS — Yellowish-green, evidently flattened, somewhat 4-sided, completely covered by closely adhering leaves, zig-zag or arranged in fan-shaped clusters. BUDS — Leaf-buds not scaly, covered by closely adhering scale-like leaves. LEAVES — Opposite, scale-like, closely overlapping, aromatic when crushed, with very conspic- uous glandular spots on the thrifty shoots, i of an inch long, of two kinds in alternating pairs. Those on the side, of the twigs keeled; those on the face of the twigs flat. FLOWERS — Appear about April or May. Staminate and pistillate flowers usually occur on different twigs. Staminate roundish, inconspicuous and yellowish. Pistillate small, ovoid, pur- plish, with 4-6 paira of thin oval scales. FRUIT — An oblong cone with 6-12 obtuse scales, J-£ of an inch long, reddish-brown, matures in one season. Seeds oblong, winged, about i of an inch long. WOOD — Non-porous; resin passages absent; light, soft, durable, fragrant; sapwood almost white, heartwood yellowish-brown. Weighs 19.72 Ibs. per cubic foot. Used for fence posts, rails, shingles, spools, .and railroad ties. DISTINGUISHING CHARACTERISTICS— The Arbor Vitae, also known as White Cedar and Cedar, may be distinguished at any season of the year by its scale-like and closely overlap- ping leaves from all the other trees native to the State of Pennsylvania except the White Cedar. It can be distinguished from the latter, which also has scale-like leaves, by its more flattened and larger twigs, which are also more fan-shaped. The fruit of the Arbor Vitae is oblong with thin oblong scales, while that of the White Cedar is spherical with thick shield-shaped scales. RANGE — Southern Labrador west to Manitoba and Minnesota, and south along the mountains to North Carolina and eastern Tennessee. DISTRIBUTION IN PENNSYLVANIA— The Arbor Vitae is found to the north and south of Pennsylvania, but so far no authentic records are available which show that it is native to this State. It is, hcwever, found very commonly throughout the entire State as an ornamental tree and sometimes as a hedge. HABITAT — Usually found in low swampy situations on the borders of ponds, streams, and lakes, but occassionally ascends to drier ground. In the north it is often found in the sphagnum bogs with Spruce and Kir, while in the south it is usually found on the mountain slopes and tops with the Spruce and other coniferous species. IMPORTANCE OF THE SPECIES — The Arbor Vitae is one of our most valuable species for or- namental purposes. It is common throughout the State as an ornamental tree and occasionally planted for hedges. As a timber tree, however, it is surpassed by many other native species and should be planted for forestry purposes only in such habitats where other more valuable species will not grow. PLATE XXVI. ARBOR VITAE. 1. A flowering branch, x £. 2. A branch with needles and fruit, x J. 3. A cone-scale with winged seeds, natural size. 4. A winged seed, enlarged. 5. A seedling, natural size. 6. Portion of branch, natural size. PLATE XXVII. RED CEDAR. 1. A branch with pistillate flowers, x J. 2. A branch with stuminate flowers, x J. 3. A branch with needles and fruit, x i. 4. \ seedling, natural size. 5. A branch with scale-like needles and a single berry-like fruit, natural size. 6. A branch with awl-shaped needles, x J. 87 RED CEDAR. Juniperus virgnjiana, Linnaeus. GENUS DESCRIPTION— This genus comprises about 40 species of trees and shrubs in the world, of which number 16 species are native to North America and 2 to Pennsylvania. The Junipers are usually medium-sized trees or occasionally shrubs. This is possibly the most widely, distributed genus of trees in North America, since there is hardly a state in the United States in which some one or a few of the species do not grow. They have little value as timber trees since only 1 species reaches a size large enough to produce timber. The fruit of the Junipers, usually called berries, is the most distinctive character of the trees. These berries are in reality cones, but have the appearance of a berry. In addition to the species described here, the Com- mon Juniper (Juniperus communis, Linnaeus) is also native to this State. It is usually a shrub, and found only locally in the eastern and northern parts of the State. FORM— An average-sized tree usually attaining a height of 25-40 ft. with a diameter of 1-2 ft., but may reach a maximum height in the south of 120 ft., with a diameter of 3-4 feet. Crown usually deep, dense, narrow, and conic, but occasionally in old specimens broad, spreading, and round-topped. BARK — Rather tMii, often grooved, reddish-brown, peeling off Into rather long, narrow, stringy, film-like strips. See Fig. 52. TWIGS — Slender, usually four-sided and green as long as leaves persist, but after leaves have fallen are round awl reddish-brown. BUDS — Inconspicuous because they are small in size and covered with leaves. LEAVES — Two kinds are recognized, scale-shaped and awl-shaped. Scale-shaped form Is typical of the tree. They are about 1/16 of an inch long, ovate, closely appressed, acute to round at apex, dark bluish-gr^en, sometime glandular on back, and four-ranked giving the twig an angular ap- pearance. The awl-shaped, which usually occur on young trees or on vigorous shoots, are narrow, sharp-pointed, spreading, scattered, not overlapping, opposite, in 2s or in 3s. FLOWERS — Appear about April or May. Staminate and pistillate flowers usually occur on dif- ferent trees but occasionally are found on the same tree. Staminate short-stalked, yellow, con- sisting of about 10 stamens, and produced in great numbers. Pistillates small, with about 6 spreading, sharp-pointed, bluish scales. FRUIT — A dark blue berry about J of an inch in diameter, often covered with a white bloom and maturing at the end of the first or second season. Flesh sweet and covering 1-2 seeds. Fruit often persists during the winter and furnishes food for birds. Some think it necessary for the seed to pass througn the alimentary canal of birds to insure optimum germination. WOOD — Non-porous; without resin passages; with distinct red heartwood and nearly white sap- wood; light, soft, fragrant, weak, durable in contact with the soil, easily worked. Weighs 30.70 Ibs. per cubic foot. Used largely for fence posts, lead pencils, moth-proof chests and closets, interior finish, furniture, rustic work, pails, and tubs. DISTINGUISHING CHARACTERISTICS — The Red Cedar, also known as Red Juniper, Cedar, and Savin, can readily be distinguishad from all the other conifers of Pennsylvania except the Common or Dwarf Juniper by its berry-like fruit, if present. The Common Juniper does not have the scale-like leaves of the Red Cedar, and the awl-shaped leaves of the Red Cedar are generally darker on the upper surface and not regularly in 3s. The awl-shaped leaves of the Common Juniper occur regularly in 3s, are larger, sharper-pointed than those of the Red Cedar and diverge almost Pt right angles. The Red Cedar also reaches a larger size and is usually more erect, but bears less conspicuous winter buds. See "Distinguishing Characteristics" under White Cedar for comparisons with this species. RANGE — Nova Scotia west to Ontario and South Dakota, south to Florida and Texas. The Com- mon Juniper has the widest range of any tree in the northern hemisphere. DISTRIBUTION IN PENNSYLVANIA— Found throughout the State. Usually solitary and scattered in abandoned fields and along fences. Sometimes in dense pure stands. Pure stands occur in Franklin, Lancaster, Montgomery, and Bucks counties. Common on red shale soil. HABITAT — It will accept almost any location from a swamp to a poor rocky cliff but reaches its best development in the swamps and alluvial soils of the southern states. Limestone soil is favorable to its growth. Abundant light is necessary for optimum development but it will tolerate shade for many years. IMPORTANCE OF THE SPECIES — The Red Cedar produces a valuable wood but grows very slowly. Other more valuable and more rapid growing species will thrive upon the same areas and bring much earlier returns. It is also subject to the attack of numerous fungous diseases, espec- ially when young. Many ornamental varieties and forms have been developed which are highly prized for landscape work. 88 THE WILLOW FAMILY— SALICACEAE. The Willow family comprises about 200 species belonging to two genera, the well-known Willows and the Aspens or Poplars. The members of this family comprise both trees and shmbs found chiefly in the north temperate and arctic zones. A few shrubby species extend far into the arctic regions. They usually prefer moist habi- tats but may also be found on drier locations. One is very apt to associate the Willows with wet habitats. The flowers appear in early spring, usually before the leaves. The staminate (male) and pistillate (female) flowers are produced on different trees. A tree bearing staminate flowers does not bear the pistillate. As a consequence one will find fruit only upon pis- tillate trees. The pistillate flowers are fertilized by insects, usually bees, which carry the pollen from the staminate flowers. The fruit consists of capsules which split into 2-4 parts and are arranged in drooping tassel-like clusters. The fruit matures in late spring at about the same time that the leaves reach their full size. The seeds are small and surrounded by a dense covering of long white hairs which aid considerably in their dispersal. The seeds must germinate soon after they mature or they will lose the power of germination. The bark is usually rather bitter. The representatives of both genera are noted for their remarkable ability to grow both from root and shoot cuttings. One can cut a small twig from a tree, put it into moist ground, and feel assured that it will grow. They also sprout very freely from stumps ir- respective of the age of the stump. The following key will distin- guish the two genera belonging to this family. KEY TO THE GENERA. Page. 1. Buds with one bud-scale; bracts of the catkins entire; stamens fewer than 10, usually 2 Salix 88 1. Buds with more than one bud-scale; bracts of the catkins fringed or lobed; stamens usually 10 or more, Populus &4 THE WILLOWS— SALIX (Tourn.) L. This genus comprises about 175 species of which number about 100 species are native to North America and about 15 species to Pennsyl- vania. The members of this family are met as trees and shrubs. Most of our native species are small trees or shrubs. Those which 89 attain tree-size are usually found near buildings and have been in- troduced. The Willows produce wood which is light, soft, not durable, and weak. It is of little commercial importance. The value of the Wil- lows lies in the shoots or rods which are used in the manufacture of baskets and furniture. Some reach a large enough size to be used lor saw lumber but the trunks are usually of a poor shape and also begin early to decay in the center. They are valuable to bind the border of streams by means of their interlacing roots and thus pre- vent erosion. They may also be used to prevent the movement of shifting sands. Few trees possess such a tenacious vitality as the Willows. They live a long time after they appear to be dying and repair broken parts very readily and often replace them with new growth. They repro- duce freely by means of sprouts, cuttings, and seeds. On very wet situations, like islands or the borders of streams, they often form dense thickets to the exclusion of almost all other growths. The Willows as a group are easily recognized even by a layman. They have a characteristic external appearance which one can soon learn to appreciate. It is, however, difficult to distinguish the different Willows from each other. They sport and hybridize freely. Very often one leaves a Willow in despair because of the fact that it was impossible to identify it. Only 4 of the 15 or 20 Willows found in Pennsylvania are described below because many of them are mere shrubs and others have been introduced from the eastern hemis- phere. The Weeping Willow (Salix babylonica L.) (Fig. 37) is very common in cultivation and in some localities it has escaped cultiva- tion. It can readily be distinguished by its drooping branches. The Crack Willow (Salix fragilis L.) is a native of Europe. It is com- mon along our streams where it reaches a large tree-size. The lat- eral branches are very brittle and after a windstorm the ground around the tree is usually covered with branchlets which have cracked off, whence the name Crack Willow. KEY TO THE SPECIES.* Page. 1. Leaves persistently hairy at least beneath, S. rostrata 93 1. Leaves smooth or nearly so when mature, 2 2. Large tree; leaves narrowly lanceolate S. nigra 90 2. Shrub or small tree rarely 20 feet tall; ^aves broadly lanceolate 3 3. Capsules pubescent; petioles and stipules not glandular; buds large S. discolor 92 3. Capsules glabrous; petioles and stipules glandular; buds small, S. lucida 91 *It is not intended that this key will enable one to distinguish all the species of Willow found in Pennsylvania. It simply aims to point out the distinguishing characteristics of the four species which are described here. Other species may be distinguished by the use of Porter's Flora of Pennsylvania. 90 BLACK WILLOW. Salix nigra, Marshall. FORM— Largest of our native tree-willows, usually 25-30 ft. high with a diameter of 10-20 inches, but may reach a height of 60-80 ft., with a diameter of 2-3 feet. Trunks usually crooked, often inclined and occurring in small groups. Crown wide, open and round-topped. BARK — Thick, rough, deeply furrowed, blackish-brown, with wide ridges covered with thick scales. Ridges of bark often connected by narrow, transverse or diagonal ridges. TWIGS— Slender, smooth, brittle, drooping, bright reddish-brown to orange colored. BUDS— Alternate, small, about J of an inch long, sharp-pointed, reddish -brown, covered by a single scale. LEAVES — Alternate, simple, narrowly-lanceolate, very long-pointed, tapering or slightly rounded at base, finely serrate on margin, usually smooth and dark green above, pale green below. LEAF-SCARS — Alternate, narrow, with 3 bundle-scars in a lunate line. Terminal scar often larger than lateral ones. Stipule-scars large and prominent. FLOWERS — Appeal in March or April before the leaves. Staminate and pistillate flowers oc- cur on separate trees, and both are borne in drooping aments or catkins from 1-3 inches long. FRUIT — A reddish-brown, smooth, ovate capsule which splits open and liberates many small seeds. Seeds cohered with a dense tuft of fine long hairs. WOOD — Diffuse-porous; with very inconspicuous medullary rays; reddish-brown, soft, weak, firm, close-grnined, not durable. Weighs about 28 Ibs. per cubic foot. Used mainly for fuel and charcoal. DISTINGUISHING CHARACTERISTICS— The Black Willow is the largest of our native Wil- lows. The rough thick-scaled, blackish-brown bark is characteristic. The narrowly -lanceolate and short-petioled leaves which are always smooth or nearly so are also distinctive. The trunks often occur >.n small groups. The slender drooping branches are easily broken off at their ends. RANGE — New Brunswick to Florida, west to Dakota, Kansas, southern Arizona and central California. DISTRIBUTION IN PENNSYLVANIA— Throughout the State. Most common in eastern and southern parts. HABITAT— Prefers moist or wet situations like banks of streams and lakes. Requires plenty of light. Occasionally found on moist, gravelly and sandy soil. IMPORTAN9E OF THE SPECIES— The Bla«k Willow is the largest tree-willow native to our flora and is very conspicuous in its appearance. It is of no present or prospective value except as a soil coaseiver and £o a limited extent as a producer of fuel wood and charcoal. Other more valuable and more attractive trees should be grown in place of it. PLATE XXVIII. BLACK WILLOW. 1. A staminate flowering branch, x |. 2. A staminate flower, enlarged. :i. A pistillate flowering branch, x J. 4. A pistillate flower, enlarged. .". A fruiting branch, x J. 6. A seed with hairs, enlarged. 7. A winter twig, x 5. 8. Section of a winter twig with bud and leaf-scar, enlarged. 9. A leafy branch, x J. PLATE XXIX. SHINING WILLOW. 1. A staminate flowering branch, x j. 2. A staminate flower, slightly enlarged. 3. A pistillate flowering branch, x 4. 4. A pistillate flower, slightly enlarged. 5. Section of a fruiting branch, x J. 6. A branch with mature leaves, x 1. 91 SHINING WILLOW. Salix lucida, Muhlenberg. FORM — A shrub or small tree sometimes reaching a height of 25 ft. with a diameter of 8 inches. TruuK short, bearing rather ascending branches which form a rather symmetrical and broad crown. BARK — Smooth, thin, bitter, brown to reddish-brown. TWIGS — Shining, yellowish-brown, later dark brown. BUDS — Alternate, smooth, ovate, pointed, about 1 of an inch long, covered by a single yel- lowish-brown scale. LEAVES — Alternate, simple, broadly lanceolate to ovate, long-pointed at apex, tapering or rounded at base, finely toothed on margin, smooth and shining above, paler below. LEAF-SCARS — Alternate, somewhat raised, lunate, with 3 conspicuous bundle-scars. FLOWERS — Appear in catkins about April before the leaves have unfolded. Staminate and pistillate flowers occur on separate trees. The starninate have five stamens, and are arranged in dense flowered catkins about 1 to li inches long. The pistillate are arranged in slender catkins from li-2 inches long. FRUIT — A narrowly-ovoid, smooth, dull, evidently-stalked, straw-colored to pale brown or greenish capsule which is evidently-rounded at the base. WOOD — Same as that of other Willows. See description under Black Willow, page 90. DISTINGUISHING CHARACTERISTICS— The Shining Willow, also known as Glossy Willow, may be distinguished by its shining leaves which are lanceolate to ovate in outline, and by its glandular petioles and stipules. The shining brownish or yellowish twigs are also characteristic. The capsules are smooth and the staminate flowers usually have 5 stamens. RANGE — Newfoundland to Manitoba, south to Pennsylvania, west to Kentucky and Nebraska. DISTRIBUTION IN PENNSYLVANIA— Locally throughout the State except in the southern part. HABITAT — Prefers wet habitats. Common along streams, on islands, and in wet semi-boggy situations. IMPORTANCE OF THE SPECIES — The Shining Willow is a very common shrub or small tree in wet situations throughout this State. The wood is of no commercial importance. The tree often acts as a soil binder upon areas where erosion is to be feared. It is also one of the most attractive of our small Willows, both in its natural haunts and artificial environments. 92 GLAUCOUS WILLOW. Salix discolor, Muhlenberg. FORM — A sli rub or small tree usually from 6-15 feet high but may reach a height of 25 ft. with a diameter of 8 inches. Trunk short and bearing stout ascending branches which form a rouad-topped crown. BARK — Thin, smooth, occasionally scaly, reddish-brown. TWIGS — At first hairy, later smooth, stout, reddish-purple to dark green, rather flexible. BUDS— Alternate, closely appressed, flattened, pointed, about J-$ of an inch long, covered by a solitary shining reddish-purple scale. Flower-buds much larger than leaf-buds. LEAVES — Alternate, simple, elliptic to oblong-lanceolate, sharp-pointed at apex, rounded at base, coarsely toothed on margin, glaucous or white beneath, green and smooth above. Petioles and stipules rot glandular. LEAF-SCARS — Alternate, somewhat raised, lunate, contain 3 bundle-scars. FLOWERS — Appear in March on twigs of previous season's growth before the leaves unfold. Staminate and pistillate flowers occur on separate trees; catkins densely flowered, with brown- tipped bracts. FRUIT — A large, hairy, long-beaked, light brown capsule. WOOD — Same as that of other Willows. See description under Black Willow, page 90. DISTINGUISHING CHARACTERISTICS— The Glaucous Willow, also known as Pussy Willow, may be distinguished by its lanceolate to elliptic leaves which are smooth and bright green above and glaucous beneath. The blossoms are thick, about half as wide as long. Capsules are pube- scent. The scales of the blossoms are clothed with long shining hairs. RANGE — Nova Scotia and Manitoba, south to Delaware and Missouri. DISTRIBUTION IN PENNSYLVANIA — Locally throughout the State. Rather common along the main streams and their tributaries. HABITAT — Prefers wet habitats such as one nnds along streams, on the border of lakes, in swamps and semi-boggy situations. Occasionally on moist hillsides. Planted specimens often grow on rather dry situations. IMPORTANCE OF THE SPECIES — The Glaucous Willow produces wood which is of no special commercial importance. The main value of the tree lies in its attractive blossoms which appear early in spring before the leaves have unfolded. It also possesses a rather handsome form and attractive bark. PLATE XXX. GLAUCOUS WILLOW. 1. A staminate flowering branch, x J. 2. A staminate flower, slightly enlarged. 3. A pistillate flowering branch, x J. 4. Section of a fruiting branch, x I. 5. A pistillate flower, slightly enlarged. 6. A branch with mature leaves, x 1. 7. A winter twig, x J. 8. Section of a twig with a bud and leaf-scar, enlarged. PLATE XXXI. BEAKED WILLOW. 1. A staminate flowering branch, x *. 2. A staminate flower, slightly enlarged. 3. A pistillate flowering branch, x J. 4. Section of a fruiting branch, x j. 5. A pistillate flower, . slightly enlarged. 6. A branch with mature leaves, x i. 7. A winter twig, x 5. 8. Section of a twig witli a bud and leaf-scar, enlarged. 93 BEAKED WILLOW. Salix rostrata, Richards. FORM — Shrub or small tree, rarely exceeding 20 ft. in height, usually 6-10 ft. high and 3-4 inches in diameter. Trunk short, often inclined and twisted. Crown broad and .round-topped. BARK — On trunk thin, smooth, sometimes shallowly fissured, usually scaly, bitter, reddish, grayish, or olive-green. TWIGS — At first hairy, later smooth, slender, purplish to brown, with projecting leaf-scars and few lenticels. BUDS — Alternate, oblong, narrow, blunt-pointed, about I of an inch long, covered by a single light chestnut-brown scale. LEAVES — Alternate, simple, elliptic to oblong, lanceolate, short-pointed to sharp-pointed at apex, wedge-sliaped or rounded at base, sparingly toothed or entire on margin, dull green and smooth on upper surface, pale green and prominently veined and hairy on lower surface, 1-3 inches long, and i-1 inch wide. LEAF-SCARS — Alternate, conspicuous, lunate, somewhat elevated, with 3 conspicuous bundle- scars. FLOWERS — Appear about April or May before or during the unfolding of the leaves. Pistillate and staminate flowers occur on different trees. The staminate have 2 stamens with smooth filaments and ere arranged in erect and terminal catkins about 1 inch long. The pistillate have hairy and evidently-stalked ovaries and are arranged in catkins about 2-2J inches long. FRTJIT — A narrowly -ovoid, hairy, evidently-beaked and stalked capsule. WOOD — Diffuse-porous; with very inconspicuous medullary rays. Similar to the wood of other Willows. See description under Black Willow, page 90. DISTINGUISHING CHARACTERISTICS— The Beaked Willow, also known as Bebb's Willow, may be distinguished by its elliptic to oblong-lanceolate leaves which are usually prominently veined and hairy on lower surface. The pubescent, evidently-stalked and beaked capsules are also characteristic. The bracts of the catkins are yellow while those of the closely related Glacuous Willow are reddish-brown. RANGE — From the valley of the Mackenzie River within the Arctic Circle and the valley of the St. Lawrence to Alaska, south to Pennsylvania, and west to Minnesota and Idaho. One of the most widely distributed species of Willow. DISTRIBUTION IN PENNSYLVANIA — Found in the northeastern and northern parts of the State. HABITAT — Prefers moist or wet situations but will grow on dry hillsides. Common in swamps and along the borders of streams. In Canada often produces twisted stems which form almost impenetrable thickets. IMPORTANCE OF THE SPECIES — This species is of no commercial and of little economic importance In Pennsylvania. This is its southern limit. It remains small and is not abundant. Like most of the Willows, it grows in wet situations and will aid in binding the soil, thus preventing erosion and wash-outs. 94 THE ASPENS AND COTTONWQOIXS— POPULUS (Tourn.) L. This genus comprises about 27 species native to the north temper- ate and arctic zones, of which number 19 are native to North America and 4 to Pennsylvania. The trees belonging to this genus have many common names, as Aspens, Cottonwoods, Poplars, or Popples. Although some of them are called Poplar, still they are in no way related to the well-known Yellow Poplar or Tulip Tree winch belongs to the Magnolia family. The leaves of some of the representatives become very conspicuous on account of their trembling or quaking habit. This fluttering of the leaves, even when only a slight breeze is at hand, is due to their laterally compressed leaf-stalks. The buds of a few species are evi- dently resinous and often pungent. Possibly no group of trees, ex- cept the Willows, is so well equipped to disseminate its seeds. The seeds are very light, produced in great abundance, and furnished with a dense covering of long white hairs which aid in their dispersal. The wood of the members of this genus is just beginning to be of commercial importance. It was formerly despised but is now used for various purposes, especially for paper pulp. These trees have some valuable merits in that they grow very fast, often on situations where other species refuse to grow, especially in wet places, and may easily be reproduced by cuttings, sprouts, or seeds. In addition to the 4 species described and contained in the sub- joined key, a few other species are rather common throughout the State especially as ornamental trees. The White or Silver-leaf Poplar (Populus alba L.) is a native of Europe and Asia but very common as an ornamental tree. It can be distinguished by its lobed leaves, covered by a dense white persistent wool on the lower surface, and by its twigs, usually covered with white cottony felt which rubs off easily. The Lombardy Poplar (Populus nigra var. italica Du Koi) is frequently cultivated in this State. It can best be distin- guished by its form (Fig. 36). The lateral branches are almost erect forming] a high but ina'rrow cprcywni., The leaves have flattened petioles, are finely toothed, smooth, and sharp-pointed. The Balm of Gilead (Populus candicans Ait.), sometimes regarded a variety of the Balsam Poplar, is occasionally found as a cultivated tree and frequently escapes cultivation. It can be recognized by large- resi- nous buds, reddi§h-brown twigs, and its ovate leaves with round or channeled petioles and heart-shaped base. The leaves of the closely related Balsam Poplar (Populus balsamifera L.) do not have a cor- date base. 95 SUMMER KEY TO THE SPECIES. Page. 1. Leaves with round or channeled petioles; twigs with orange colored pith, P. hetterophylla 98 1. Leaves with flattened petioles; twigs with white pith, 2 2. Leaves broadly deltoid, abruptly acuminate; stigma-lobes expanded in all direc- tions, P. deltoides 99 2. Leaves broadly ovate to nearly round, usually acute at apex; stigma-lobes thread- like, 3 3. Leaves finely serrate on margin; bark greenish-white P. tremuloides 96 3. Leaves coarsely dentate on margin; bark yellowish-gray to black, P. grandidentata 97 WINTER KEY TO THE SPECIES. 1. Terminal buds 5 to I of an inch long, decidedly resinous; lateral branches with a tend- ency to become vertical, P. deltoides 99 1. Terminal buds about } of an inch long, devoid of resin or only slightly resinous; lateral branches without the vertical tendency '. 2 2. Twigs with orange-colored pith P. heterophylla 98 2. Twigs with white pith 8 3. Buds smooth, glossy, conical, sharp-pointed; often incurved and closely appressed, bark greeni?h-white, P. tremuloides 96 3. Buds downy, dull, ovate, blunt-pointed, straight, divergent; bark yellowish-gray to black P. grandidentata W 96 AMERICAN ASPEN. Populus tremuloides, Michaux. FORM— A small tree usually 30-40 ft. high but may reach a height of 80 ft. with a diameter of 20 inches. In Pennsylvania usually very small. Trunk continuous, tapering, bearing slender, brittle, and rather ascending lateral branches. Crown high, narrow, rather round-topped. BARK — On old trunks thick, deeply fissured and black; on upper portion of trunk and young stems yellowish-green to white, with dark blotches below the branches. Usually whiter at high altitude. TWIGS — Rather slender, reddish-brown, glossy, smooth, round, sometimes covered with a scaly bloom; marked by reddish-yellow lenticels; roughened by leaf -scars; pith white and 5-angled. BUDS — Alternate, narrowly conical, sharp-pointed, smooth, shiny, usually appressed, often incurved; covered by 6-7 reddish-brown, smooth, shiny, bud-scales; basal scale of lateral buds outside. LEAVES — Alternate, simple, ovate to nearly round, cordate to truncate at base, acute at apex, finely serrate on margin, 1J-2 inches long, thin, dark green and shiny above, pale green below. Leaf-stalks laterally flattened. LEAF-SCARS — Alternate, large, conspicuous, lunate, with a cork-like surface; bundle-scars 3, simple or compounded. Stipule-scars linear, blackish, rather distinct. FLOWERS — Appear about April. Staminate and pistillate flowers occur on different trees. Staminate aments drooping, 15-21 inches long, bearing many closely packed individual flowers with 6-12 stamous. Pistillate aments drooping, 1J-2J inches long; when mature 4 inches long, bearing relatively few individual flowers with thick stigmas divided into thread-like lobes. FRUIT — An oblong-conical capsule, 2-valved, light green, borne on a drooping stalk about 4 inches long. Seeds light brown, surrounded by a mat of long, soft, white hairs. WOOD — Diffuse-porous; medullary rays very fine and indistinct; pores very minute, invisible without a lens. Fine in texture, light brown to white in color, neither strong nor durable. Weighs 25 Ibs. per cubic foot. Used for paper pulp, boxes, jelly buckets, lard pails, spice kegs, wooden dishes. DISTINGUISHING CHARACTERISTICS — The American Aspen, also known as Quaking Aspen, Trembling Aspen, Small-toothed Aspen, Popple, Poplar, and Aspen, may be distinguished by the round or ovate leaves which have a finely serrate margin and are short-pointed. The petioles of the leaves are decidedly flattened which causes them to tremble or flutter in response to even a light breeze, whence the name Trembling Aspen. The alternate, sharp-pointed, conical, often incurved, closely appressed, shiny buds are also characteristic. The buds of the closely related Larg^-toothed Aspen are stouter, not so sharp-pointed, usually divergent, and covered with a flour-like, crusty, pale, woolly substance. The twigs are reddish and usually smooth while those of the Large-toothed Aspen are yellowish-brown often pale-downy or pale-scaly. The lateral branches ar2 more ascending and the bark is lighter in color than that of the Large-toothed Aspen. The bark is yellowish-green to white often marked with dark blotches. RANGE — A transcontinental species extending from Newfoundland to the Hudson Bay region and Alaska, south to Pennsylvania and along the mountains to Kentucky, west to the Rocky Mountains, Mexico, and California. The widest range of any species of tree in North America. DISTRIBUTION IN PENNSYLVANIA— Found locally throughout the State. Most common in the mountainous part. HABITAT — Found upon practically all soil conditions except swamps. Prefers dry situations. Common In abandoned fields, on cut-over areas and burns. Frequently mixed with Scrub Oak which shades out in time. IMPORTANCE OF THE SPECIES — The American Aspen is of no commercial importance in Pennsylvania. It remains too small and is too local in its distribution. Next to Spruce and Hemlock it is the principal pulpwood of the country. It is also beginning to be used for lumber. The wood is white and turns well. Ordinarily it is a poor competitor in the forest but it does overcome the Scrub Oak upon burnt-over areas by shading it out. It is also valuable as a temporary shelter species for other valuable trees. PLATE XXXII. AMERICAN ASPEN. 1. A staminate flowering branch, x i. 2. A staminate flower, enlarged. 3. A pistillate flowering branch, x J. 4. A pistillate flower, enlarged. 5. Section of a fruiting branch, x J. 6. A seed with hairs, enlarged. 7. A branch with mature leaves, x J. 8. A winter twig, x i. 9. Section of a twig with a bud and a leaf- scar, enlarged. PLATE XXXIII. LARGE-TOOTHED ASPEN. 1. A staminate flowering branch, x i. 2. A staminate flower, enlarged. 3. A pistillate flowering branch, x J. 4. A pistillate flower, enlarged. 5. A fruiting catkin with capsules, x J. 6. A seed with hairs, enlarged. 7. A branch with mature foliage, x J. 8. A winter twig, x J. 9. Section of a winter twig, enlarged. 97 LARGE-TOOTHED ASPEN. Populus grandidentata, Michaux. FORM — Usually a small tree 30-40 ft. high but may reach a height of 70 ft. with a diameter of 2 feet. More frequent and larger in this State than the American Aspen. Trunk continuous and tapering. Crown often irregular, due to the absence of branches which have been broken off on account of theii brittleness. Branches usually less ascending than those of the American Aspen. BARK — Near the base of old trunks black, very rough, thick, hard, does not heal over branch wounds rapidly. Large smooth surfaces found on flat ridges between fissures. Smaller branches similar to those of the American Aspen but with a more pronounced yellow color. See Fig. 95. TWIGS — Rather stout, reddish to yellowish-brown, round, often covered with a coating of pale, woolly, crusty down which occasionally peels off in small flakes. BUDS — Alternate, ovate to conical, pointed, dusty, dull, usually divergent, covered by 6-7 light chestnut-brown scales which are often coated with a dusty flour-like mat of a pale, woolly substance. Basa' scale of lateral buds on outside. LEAVES — Alternate, simple, broadly-ovate, wedge-shaped to cordate at base, acute to acuminate at apex, coarsely dentate on margin, 3-4 inches long, dark green above, pale green below. Leaf-stalks laterally flattened. LEAF-SCARS — Same as leaf-scars of American Aspen, page 96. Stipule-scars are less distinct. FLOWEiRS — See "Flowers" under American Aspen, page 96. FRUIT — An ament bearing scattered, light, green, 2-valved capsules which contain minute dark brown seeds surrounded by a mat of long white hairs. "WOOD — Same as American Aspen, page 96. DISTINGUISHING CHARACTERISTICS— The Large-toothed Aspen, also known as Popple and Poplar, may be distinguished by its coarsely wavy-toothed leaves, larger than those of the American Aspen which it closely resembles. See "Distinguishing Characteristics" under the latter. It does not have the resinous buds, nor the ridged bark on the twigs, nor the deltoid leaves so characteristic of the Cottonwood. The bark is often covered with oyster-shell-like bodies whicn are the armored portion of the oyster-shell scale. Many small trees are killed by this scale. RANGE — Xova Scotia and Ontario south to Pennsylvania, along mountains to North Carolina and west to Minnesota DISTRIBUTION IN PENNSYLVANIA — Rather common throughout the State especially on lumbered and burnt-over areas, in abandoned fields, and on charcoal hearths. Usually found in mixture, but occasionally in small pure stands. HABITAT — Prefers rather rich moist soil, but is also found on dry gravelly soil. Usually large on moist situations and smaller, often scrubby, on very dry situations. Frequent asso- ciates are Birch, Bird Cherry, Shad Bush, and Scrub Oak. IMPORTANCE OF THE SPECIES — The Large-toothed Aspen is of no commercial importance in this State. It is of value in our lumbered areas because it covers the soil rapidly, acts as a soil-conserver, and often as a soil-improver. It may also act as a temporary shelter for more valuable species while they are young and establishing themselves. It also aids in shading out our most aggressive forest weed — Scrub Oak. 98 DOWNY POPLAR. PopuluS heterophylla, Linnaeus. FORM — In the north usually a small tree from 30-50 ft. high; in the south may reach a height of 100 ft. with a diameter of 3 ft. Crown high, rather broad and round-topped. Trunk short, con- tinuous, and tapering*. BARK — On old trunks thick, light reddish-brown, rough, broken by long fissures into long narrow plates. Cn younger tiunks and large branches thinner, not so rough; fissures shallower and ridges smoother than on old trucks. TWIGS — Stout, light yellowish, marked by a few scattered pale lenticels, roughened by elevated leaf -scars; pith orange-colored. BUDS — Alternate, broadly ovate, slightly resinous, bright reddish-brown, covered with 4-7 scales which art slightly pubescent towards the base. Leaf-buds about 1 of an inch long. Flower-buds about i of an inch long. LEAVES — Alternate, simple, broadly ovate, cordate, rounded or truncate. at base, rounded or acute at apex, coarsely serrate on margin, 4-7 inches long, dark green above, pale green below; leaf -stalks round. LEAF-SCARS— Alternate, large, elevated, often 3-lobed, indented on upper margin; with 3 conspicuous bundle-scars. FLOWERS — .Appear in March or April. In general similar to the Cottonwood only both starninate and pistillate amenta are shorter. FRUIT — A drooping ament, when mature about 4-6 inches long, bearing a few, scattered, dark green, 3-4-valved capsules containing small seeds surrounded by a mat of white hairs. WOOD — Same as that of the Cottonwood only slightly heavier. See description page. 99. DISTINGUISHING CHARACTERISTICS — The Downy Poplar, also known as Swamp Cotton- wood, Black Ctttonwood, River Cottonwood, and Swamp Poplar, may be distinguished from all the Aspens. Poplars, and Cottonwoods native to this State by its round leaf -stalks. The leaf-stalks of all tte others are laterally flattened. The leaves are large and more bluntly pointed than these of the other species. The Jeaf-margins are not so finely toothed as those of the American Aspen but finer than the other' two native species. The bark on old trunks is light reddish browu. The twigs are stouter than those of the Aspens and contain orange colored pith. The Aspens have white pith. The buds are bright reddish-brown, slightly resinous, covered with scales which are often pubescent near the base. RANGE — Connecticut along coast to Georgia, west to Louisiana, and northward to Kentucky and Missouri. Its range suggests a somewhat contorted horseshoe. DISTRIBUTION IN PENNSYLVANIA — Found only in the extreme southeastern and southern parts of the State. Reported from Chester, Delaware, and Franklin counties. Very rare and local. HABITAT — Found only in low wet situations, and always mixed with other species in this State. IMPORTANCE OF THE SPECIES — This species is too rare and local to be of any commercial importance. It 1s not attractive ornamentally on account of its heavy limbs and sparse, rounded crown. The wood is not listed separately on the market but bought and sold as Cottonwood. PLATE XXXIV. DOWNY POPLAR. A staminate flowering branch, x 5. A starainate flower, enlarged. A pistillate flowering branch, x \. A pistillate flower, enlarged. Section of a branch with a fruiting catkin and capsules, x 5. A seed with hairs, enlarged. A branch with mature foliage, x J. A winter twig, x J. Section of a winter twig, enlarged. PLATE XXXV. COTTONWOOD. 1 A staminate flowering branch, x J. 2. A staminate flower, enlarged. 3. A pistillate flowering branch, x J. ». o<™,, ^ - - fruiting catkin and capsules, x 5. 6. A seed with hairs, enlarged. 7. Section of a branch with mature foliage, x J. 8. A winter twig, x J. 9. Section of a winter twig, enlarged. 99 COTTONWOOD. Populus deltoides, Marshall. FORM — A large tree usually 50-75 ft. high but may reach a height of more than 100 ft. with a diameter of 6 feet. Trunk < tapering, continuous, sometimes clean for a considerable distance from the ground. Crown usually high and pyramidal. Lower lateral branches horizontal, while most of the upper branches are decidedly ascending. BARK — On old trunks thick, ashy-gray, roughened by long deep furrows which are usually longitudinally parallel, and often connect with one another. Rather thin, smooth, and greenish- yellow on younger trunks. TWIGS — Stout, usually yellow tinged with green or brown, round or ridged below the buds; covered with large, longitudinally-elongated lenticels; pith white and angular. BUDS — Alterrate, large, resinous, glossy, smooth, chestnut-brown, covered with numerous bud-scales which are sticky, resinous on the interior and smooth on the exterior. Terminal buds often 5-angled and larger than lateral ones; lateral buds usually divergent and often recurved. LEAVES — Alternate, simple, broadly deltoid, truncate to wedge-shaped at base, acuminate at apex, coarsely serrate on margin, 3-5 inches long, thick, deep shining green above, pale green below. I-eaf -stalks laterally flattened. LEAF-SCARS — Alternate, large, lunate, elevated, depressed on upper margin, sometimes 3-lobed; with 3 bundle-scars. Stipule-scars dark and conspicuous. FLOWERS — Appear about March or April. Staminate and pistillate flowers occur on different trees. The staminate are arranged in drooping aments 3-4 inches long and are densely flowered; the pistillate, in drooping aments 2J-3J inches long and sparsely flowered. FRUIT — A drooping ament bearing dark green, 3-4-valved capsules which contain small seeds surrounded with a mat of long white hairs. Fruiting aments longer than in the other native species, 8-12 inches. WOOD — Diffuse-porous; with very indistinct rays; pores in early wood visible to unaided eyes; heartwood dark brown; sap wood wide and white; wood is soft, warps easily, and is difficult to split. Weighs about 23 Ibs. per cubic foot. Used for paper pulp, boxes, crates, berry boxes, pails, and tubs. DISTINGUISHING CHARACTERISTICS— The Cottouwood, also known as Carolina Poplar, Cotton Tree, and Whitewood may readily be distinguished at any season of the year by its lateral branches Avhich )iave a tendency to ascend like the Lombardy Poplar (Fig. 36), and by its yellowish twigs which often have prominent ridges running down from the leaf- scars. The buds are larger, more resinous, and often more flattened than those of any other member of this genus; usually divergent and often incurved. The leaves are very character- istic since they have laterally flattened leaf-stalks, are deltoid in outline, truncate at the base and long-pointed at the apex. The pores in the early wood are visible to the unaided eye while those of the American and Large-toothed Aspens are not visible. RANGE — Quebec and Ontario south to Florida, west to the Rocky Mountains. DISTRIBUTION IN PENNSYLVANIA— Natural distribution is very limited. Reported from Presque Isle, Erie county and from Lancaster county. Locally escaped cultivation. Planted extensively for ornamental purposes and in a few plantations for forestry purposes. HABITAT — Piefers rich moist soil, like banks of streams, borders of lakes, and semi- swarnps. IMPORTANCE OF THE SPECIES— The Cottonwood is planted, extensively as an ornamental tree but as such it has few merits except its rapid growth, rather attractive form in winter, and the pleasant, balsamic odor from its coated, young, developing leaves. It Is well adapted to wet locations and may be planted where other more valuable trees will not grow. It grows rapidly, and produces an excellent pulp-wood. This tree is known to grow 5 feet in a single year and 40 feet in 10 years. Cuttings taken from trees and placed in the ground grow very readily. When planted in the streets its roots often lift pavements, and clog drains and sewers. Not adapted for street planting. 100 THE WALNUT FAMILY— JUGLANDACEAE. This family comprises about 6 genera with 35 species of trees and shrubs found chiefly in the warmer portion of the north temperate zone. Two genera with about 19 species are native to North Amer- ica. Both of these genera, Juglans and Carya, have representatives in Pennsylvania. The former genus has 2 species and the latter 5 species native to the State. In addition to the existing species a great number of fossil species have been referred to this family. Thirty fossil species belonging to the genus Juglans and 10 species belonging to the genus *Carya have been described. This is one of the most important families of trees native to Penn- sylvania. Both the Hickories and the Walnuts yield very valuable wood. The wood of the Walnuts is esteemed especially for cabinet work and that of the Hickories on account of its strength and flexi- bility. The bark and husks of the Walnuts are used sometimes as a dyestuff. The fruit of both genera is edible. The staminate and pistillate flowers are separate but borne on the same tree and usually in the same branch. The staminate flow- ers are in long drooping aments while the pistillate appear as buds and occur in small few-flowered clusters. The leaves of both genera are compound and alternate. The fruit is a nut. The nut of the Walnuts is sculptured and covered with a fleshy, indehiscent, pulpy husk while the nut of the Hickories is not sculptured but covered with a dehiscent husk. KEY TO THE GENERA. Page. 1. Pith of twigs chambered; nuts sculptured or rugose with indehiscent husk; staminate catkins thick, compact, usually sessile and solitary; wood diffuse-porous Juglans 101 1. Pith of twigs continuous; nuts smooth or ridged with dehiscent husk; staminate catkins slender, loose, long-stalked, in 3s; wood ring-porous Carya 104 101 THE WALNUTS— JUGLANS, L. This genus comprises about 15 species which are found chiefly in the north temperate zone. Five species are native to North Amer- ica, two of which are native to Pennsylvania. In addition to the native species a European species known as the English Walnut (Juglans regia L.) is widely distributed in the United States as an ornamental tree. It is this European species which yields the val- uable Circassian Walnut wood used so extensively in the manufac- ture of furniture and it also produces the English walnuts so com- mon on our markets. Our native species produce materials which are of considerable commercial importance. The wood is highly prized. The nuts are delicious and valuable as a food. The bark and husks are used as dyes and tans. The wood of our species is diffuse-porous and brown to black in color. The leaves are alternate and compound. The pith is chambered. The fruit ripens in one season and consists of a sculptured or rugose nut covered by a pulpy husk which does not split open into regular segments. The kernel of the nut is 24 lobed, large and oily. The nuts are scattered mainly by rodents, which bury them for food, and by floods which carry them along their courses. SUMMER KEY TO THE SPECIES. Page. 1. Leaflets 11-17, often viscid-hairy, the terminal leaflet usually present; pith dark brown; bark gray; fruit sticky-hairy; nut elongated-ovate, J. cinerea 102 1. Leaflets 13-23, not viscid-hairy, the terminal leaflet often absent; pith light brown; bark dark brown; fruit not sticky-hairy; nut globose, J. nigra, 103 WINTER KEY TO THE SPECIES. 1. Bark gray; pith dark brown; nut elongated-ovate; upper surface of leaf -scar not notched; hairy transverse fringe above leaf -scar present; terminal buds evidently flattened, not less than J of an inch long, J. cinerea 102 1. Bark dark brown; pith light brown; nut globose; upper surface of leaf -scar notched; hairy fringe above leaf -scar absent; terminal buds slightly flattened, J of an inch or less in length ' J. nigra 103 102 BUTTERNUT. Juglans cinerea, Linnaeus. FORM — A small to medium-sized tree usually attaining a height of 30-50 ft. with a diameter of 1-2 ft., but may reach a height of 80-100 ft. with a diameter of 3-4 feet. Trunk usualy short, like that of tht- apple tree. Crown usually broad, deep, round-topped, rather open, often unsymmetrical. BARK — On branches and young trunks rather smooth, light gray; on older trunks roughened by black fissures which separate wide, smooth, light gray ridges. Inner bark bitter, light In color, becoming yellow on exposure. See Fig. 80. TWIGS — Alternate, stout, round; at first hairy and sticky, later smooth; roughened by leaf -scars, bitter to taste, greenish-gray to buff in color, covered with a few pale lenticels; pith chambered, dark brown. If chewed, twigs and young bark color saliva yellow. BUDS — Alternate, covered with dense pale down. Terminal bud J-3 of an Inch long, flattened, blunt-pointed with its outer scales lobed. Lateral buds smaller than terminal, ovate, very blunt-pointed, often superposed. Scaly cone-like lateral buds often present. These are In reality partially developed catkins. LEAVES-— Alternate, compound, 15-30 inches long, with 11-17 leaflets. Leaflets 3-5 Inches long, serrate on margin, acute at apex, unequally rounded at base and usually sessile or nearly so. Petioles hairy and sticky. LEAF-SCARS — Alternate, large, 3-lobed, concave, with raised margins, with 3 clusters of bundle-scars arranged in a U-shaped line. Upper margin of leaf -scar usually convex, rarely notched. FLOWERS— Appear about May when leaves are half developed. Staminate and pistillate flowers separate, but occur on the same tree and usually on the same branches. Staminate arranged in unbranched catkins, which become 3-5 inches long. Pistillate produced in 6-8-flowered spikes. FRUIT — An elcngated-ovate sculptured nut covered with a fleshy indehiscent husk. Husk very hairy and sticky. Nut four-ribbed, pointed at one end; contains a sweet edible and very oily kernel. WOOD — Diffuse-porous with ring-porous tendency; with inconspicuous medullary rays; soft not strong, light brown, and coarse-grained. Weighs 25.46 Ibs. per cubic foot. Used in furniture, interior finishings, and occasionally in church altars, ceiling, and flooring. DISTINGUISHING CHARACTERISTICS— The Butternut, also known as White Walnut and Oilnut, resembles the Black Walnut, but is distinguished from it by its shorter and light- barked trunk, dark brown pith, larger and more flattened terminal buds, lighter colored Avood, elongated-ovate fruit, unnotched upper margin of the leaf-scar with a hairy fringe above It. RANGE — New Brunswick and Quebec, west to Minnesota, and south to Delaware and Arkansas, and along the mountains to Georgia. DISTRIBUTION IN PENNSYLVANIA — Local throughout the State in rich bottomlands and on fertile hillsides. Very common locally in the southeastern and southern parts. HABITAT — Prefers rich moist soil. Common along fences, streams, and roads. Occasionally found on high mountains. IMPORTANCE OF THE SPECIES— The Butternut can hardly be classified as a valuable timber tree. It produces a beautiful wood and delicious nuts but the trees seldom reach a large size. The old trees are very susceptible to the attack of wood-destroying fungi. The tree is attractive ornamentally. It branches freely often forming many crooks and crotches which yield the highly floured wood. PLATE XXXVI. BUTTERNUT. 1. Branch with one-half developed leaves, (s) 3 unbranched catkins of staminate flowers, and (p) a cluster of pistillate flowers, x J. 2. A mature leaflet, x i. 3. A staminate flower, slightly enlarged. 4. A pistillate flower, slightly enlarged. 5. A cluster of mature fruit, x J. 6. A winter twig showing buds, lenticels, leaf- scars, and pith, x J. 7. Longitudinal section of twig showing cham- bered pith, slightly enlarged. 8. Section of winter branch showing leaf-scars, hairy fringe above leaf-scars and superposed buds, slightly enlarged. 9. A nut with husk removed, x J. 10. A terminal bud, natural size. 11. A terminal bud (broad-side view), natural size. 12. Section of a branch showing superposed lat- eral flower buds, enlarged. PLATE XXXVII. BLACK WALNUT. f staminate flowers and (p) 1. I'ranch with developing leaves and (s) three solitary catkin a spike with three pistillate flowers, x J. 2. A stain innte flower, slightly enlarged. 3. A pistillate flower, slightly enlarged. 4. A branch with a mature leaf and fruit, x \. 5. A winter twig, x J. 6. Longitudinal section of twig showing chambered pith, enlarged. 7. Section of twig showing superposed and gaping buds, and leaf-scars with 3 clusters of bundle- scars and notched upper surface, slightly enlarged. 8. A nut with husk removed, x J. 9. Terminal section of winter twig showing leaf-scar and terminal bud with bud-scales, slightly enlarged. 103 BLACK WALNUT. Juglans nigra, Linnaeus. FORM— A large tree, usually attaining a height of 80-100 ft. with a diameter of 2-3 ft., but may reach a height of 150 ft. with a diameter of 6-8 feet. Trunk usually straight, clean, slightly tapering, bearing a round-topped crown. BARK — Semi-fibrous, thick, rough, longitudinally and occasionally diagonally fissured. Outer bark dark brown to grayish-black. Inner bark light, but turns yellow upon exposure. See Fig. 81. TWIGS — At first hairy, later smooth, orange-brown to dark brown, stout, covered with rather inconspicuous, somewhate raised lenticels; pith light brown, chambered. BUDS — Alternate, covered with thick, pubescent scales. Terminal buds usually less' than J of an inch long, flattened, ovate, blunt-pointed. Lateral buds usually less than 1/6 of an inch long, obtuse at apex, often superposed. LEAVES — Alternate, compound with 13-23 leaflets. Leaflets 3-4 inches long, oblique at base, acute at apex, serrate on margin, almost sessile and arranged opposite or alternate to each other. LEAF-SCARS — Alternate, large, 3-lobed, often heart-shaped, raised; upper margin notched in which an axillary bud is often located. Bundle-scars grouped in three clusters, arranged in a U-shaped line. FLOWE3.S — Appear in May when the leaves are about half developed. Staminate and pistillate flowers separate, but occar on same tree and usually on same branch. Staminate arranged in unbranched catkins. Pistillate produced in 2-5-flowered spikes. FRUIT — A sculptured nut with a fleshy indehiscent covering. Nut round, very rough, 1-2 inches in diameter, occurs solitary, in pairs, sometimes in 3s; contains an edible somewhat oily kernel. WOOD — Diffuse-porous with a ring-porous tendency; medullary rays inconspicuous; rich dark brown, very durable, hard, strong, splits easily, takes glue well. Weighs 38.11 Ibs. per cubic foot. Used in furniture, interior finishings, musical instruments, automobiles, sewing machines, fire-arms. DISTINGUISHING CHARACTERISTICS— The Black Walnut, also known as Walnut, some- what resembles the Butternut or White Walnut but bears little resemblance to other trees. It may be distinguished from the Butternut by its light brown chambered pith, shorter and less flattened terminal buds, darker bark, larger size, more globose nut, notched upper margins of leaf -scars, and the absence of a hairy fringe above the leaf-scar. RANGE — New England and New York to Minnesota, and south to Florida. DISTRIBUTION IN PENNSYLVANIA— Local throughout the State in rich bottomlands and on fertile hillsides. HABITAT — Prefers rich moist soil. Requires plenty of light and deep soil since it is evidently tap-rooted. IMPORTANCE OF THE SPECIES— The Black Walnut is one of the most valuable timber trees native to this State. It reaches a large size, is attractive ornamentally, and produces wood valuable for its color, figure, and the fine polish which it takes. The nuts are highly prized. Forest grown trees rarely produce much fruit. Open grown trees produce abundant fruit and often highly figured wood. 104 THE HICKORIES— CAKYA, Nuttall. The Hickories and the Walnuts belong to the same family. All species of Hickory, so far as known, are native to the part of North America lying east of the Rocky Mountains. Geological records in- form us that the ancient forests of hickory extended into Greenland and Europe. None of the fossil species shows evidence of living after the ice age. This suggests the presumption that the hickory forests were completely destroyed by sheets of ice advancing from the North towards the South. These sheets covered a large part of Europe and North America. To-day no native species of Hickory are found in Europe, showing that they were completely exterminated during the ice age. In North America the ice covered only a portion of the range of hickory. Hickory is found today not only in the non- glaciated region of North America but in addition it has regained some of the lost territory. The northern limit of Hickory is, how- ever, still about 1,000 miles south of its northern limit in the ancient flora of Greenland. The range of some of the more important species of Hickory has been extended by man. The Hickories have alternate, compound and odd-pinnate leaves. The leaf-scars are large and conspicuous. The flowers are unisex- ual. The staminate or male (pollen -bearing) flowers are produced in long slender, drooping aments. The aments are usually in 3s, united near the base of twig into a common stalk which is attached to the twig at the base of the new growth. The pistillate or female flowers which develop into the fruit occur at the end of the season's twigs in spike-like clusters of 2-0. The fruit resulting from the development of the pistillate flowers matures in one season. The nuts are ovoid to cylindrical and covered with a husk which is 4-valved. In most species the husk splits open at least to the middle when it becomes dry but in a few species it separates very little. The Hickories are amongst our most important timber trees. They are not important because they produce a large quantity of wood but because they produce a special quality of wood used for special purposes for which no substitutes have been found. The wood is unsurpassed for such uses where strength combined with lightness is desired. It is largely used for handles and in the manufacture of our best carriages, especially in the construction of the wheels. Not all of the species, however, produce valuable wood. The wood of the Bitter Nut Hickory is relatively of little value. The nuts of a few species are edible. These nuts were used for food and for oil by the Indians and at the present time they are used extensively 105 for food. The most valuable and edible nuts are obtained from the Shag-bark Hickory (Carya ovata). This genus comprises about 10 species found in eastern North America and .1 species in Mexico. Six species are native to this State. One species, the small-fruited Hickory (Carya microcarpa, Nutt. ) , sometimes considered a variety of the Pignut Hickory, is found locally in the State but not described in this publication. In addi- tion to our native species the Pecan Hickory (Carya illinoensis) is planted extensively for ornamental purposes and for the sweet nuts which it produces. SUMMER KEY TO THE SPECIES. Page. 1. Leaflets 7-11, small, lanceolate, usually curved, C. cordiformis 110 1. Leaflets 5-7, larger, broader than lanceolate, rarely curved, 2 2. Husk of fruit splits tardily into 4 valves; valves of fruit thin and rather friable at • maturity; tAvigs smooth, relatively slender, cherry-colored to gray, C. glabra 109 2. Husk of fruit splits promptly into 4 valves; valves of fruit thick and hard at maturity; twigs often hairy towards tip, rather stout, buff, gray, or brownish 3 3. Bark closo, rough but not shaggy on old trunks; twigs relatively stout; foliage scurfy or pubescent, C. alba 108 3. Bark shaggy separating into long plates on old trunks; twigs not so stout; foliage smooth or sometimes downy beneath, 4 4. Leaflets usually 7; nuts dull white or yellowish and pointed at both ends, C. laciniosa 107 4. Leaflets usually 5; nuts white, rounded or notched at the base, C.- ovata 106 WINTER KEY TO THE SPECIES. 1. Buds yellow with 4-6 bud-scales valvate in pairs; lateral buds often evidently- stalked; terminal buds elongated and flattened, C. cordiformis 110 1. Buds not yellow, truly scaly; bud-scales 10 or more usually overlapping, except outer ones on lateral buds which may form a closed sac but in time split from the top; inner scales hairy 2 2. Buds small; terminal buds 1/5 to 2/5 of an inch long, their outer scales glandular dotted; twigs smooth, relatively slender, cherry-colored to gray; husk of fruit thin, not freely splitting to base, with thin-shelled nut, C. glabra 109 2. Buds large; terminal buds 2/5 to 3/5 of an inch long, their outer scales almost glandless; twigs often hairy towards tip, rather stout, buff, gray, or brownish; husk of fruit thick, freely splitting to base, 3 3. Twigs relatively stout; bark rough and close, not shaggy; nut brownish, thick- shelled, with small kernel; terminal buds broadly-ovate with their outer scales early deciduous, C. alba 108 3. Twigs not so stout; bark shaggy; nut white, dull-white, or yellowish with large kernel; terminal buds elongate-ovate with their outer scales tardily deciduous 4 4. Nuts dull white or yellowish and pointed at both ends C. laciniosa 107 4. Nuts white, rounded or notched at the base, C. ovata 106 106 SHELL-BARK HICKORY. Carya ovata, (Miller) K. Koch. FORM— A large tree usually reaching a height of 50-75 ft. with a diameter of 2 ft. but may reach -a height of 120 ft. with a diameter of 3-4 feet. Trunk straight, slender, in dense stands free from branches for the greater part of its length; in open grown trees short, with an oblong-cylindrical high crown. BARK — On old trunks shaggy, light gray, 2/5-1 inch thick, peeling off in rough strips or plates which are usually loose at both ends and fastened in the middle. On young trunks smooth and light gray. See Fig. 88. TWIGS — Intermediate in thickness between the Mocker Nut and the Pignut Hickory, usually slightly downy, sometimes smooth anl glossy; reddish-brown to grayish, covered with numerous conspicuous and longitudinally-elongated lenticels; pith angular. BUDS — Alternate, more than 2-ranked. Terminal bud broadly ovate, blunt-pointed, 2/5-4/5 of an inch long, usx^ally covered by about 10 bud-scales. The 3-4 outer scales dark brown, broadly triangular, sharp-pointed, often hairy especially along margin, sometimes smooth, and often with the apex terminating in a long rigid point. Inner scales increase in size in spring, are tardily deciduous, yellowish-green or reddish, densely downy on outer surface and smooth within. LEAVES — Allernate, compound, with 5-7 leaflets, 8-14 inches long. Leaflets differ in size; basal pair small, relatively short and widest near the base; upper pair obovate and larger than basal pair; terminal large and obovate. Leaflets serrate on margin, acute at apex, tapering or rounded at base, usually smooth but sometimes hairy on lower surface. LEAF-SCARS — Alternate, more than 2-ranked, large, conspicuous, somewhat raised, heart- shaped or 3-lobed or inversely-triangular or sometimes elliptical, containing numerous con- spicuous bundle-scars which are distributed irregularly or grouped in 3 clusters or arranged In a curved line. FLOWERS — Appear about May when leaves are almost fully developed. Staminate and pistil- late flowers occur separately. Staminate hairy and arranged in aments which are clustered In 3s and 4-5 inches long. Pistillate rusty-woolly arranged in 2-5 large spikes. FRUIT — Globular or depressed at apex, 1-2 inches long, with a thick husk which splits into four pieces completely to the base. Nut white, oblong, somewhat flattened, ridged, barely tipped with a point, with thin shell and large sweot kernel. WOOD — Ring-porous; pores of summer wood rather large, isolated, rather evenly distributed, not in groups or lines; medullary rays rather abundant but inconspicuous; conspicuous lines of wood parenchyma present. Wood very heavy, hard, strong, tough, elastic, close-grained, usually straight-grained, not durable in 'contact with soil. Heartwood light brown or reddish with white sapwood. Weighs from 50 to 52 Ibs. per cubic foot. Used chiefly for handles and light vehicles. Valuable for fuel and smoking meat. DISTINGUISHING CHARACTERISTICS— The Shell-bark Hickory, also known as Shag-bark Hickory, can be distinguished from the Bitter Nut Hickory by means of its larger many-scaled buds which are not flattened nor yellow, and by its bark which is shaggy, while that of the latter is close and rough. The bark of the Pignut Hickory, is also close and rough. The Pignut Hickory has scaly buds but they are much smaller than those of the Shell-bark Hickory. The fruit of both the Pignut Hickory and Bitter Nut Hickory is smaller and has a thin tardily or non-splitting husk and a small bitter kernel, and their leaves are smoother and their leaflets narrower than those of the Shell-bark Hickories. The Mocker Nut Hickory has stouter twigs, scurfier pubescent foliage, •closer and rougher bark, and browner nuts with a small kernel. For distinguishing characteristics between Carya ovata and Carya laciniosa, see page 107. RANGE — Quebec west to Minnesota and south to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA — Most common in the southeastern and southwestern parts of the State. Rare in the mountainous parts, except locally in the valleys. Rather abundant lo- cally east of the Allegheny mountains especially in the fertile valleys and along the rich foothills. Reported rather abundant locally in the northern part. HABITAT — Prefers rich moist soil and plenty of light. Common in the valley and in moist hillside woods. Also common along streams, and on the border of swamps. IMPORTANCE OF THE SPECIES — This is a very important species on account of the valuable wood and nuts which it produces. It is not very common in the State as a whole, but where it does occur it should be protected and regenerated as much as possible. Seeds should be planted rather than seedlings because the latter are sensitive to transplanting on account of their long taproot. PLATE XXXVIII. SHELL-BARK HICKORY. 1. A flowering branch, x i. 2. A branch with fruit and a mature leaf, x 4 ?,. A nut with part of husk removed, x J. 4. A nut, x J. 5. Ciws-section of a nut showing kernel, x i. 6. A winter twig, x J. 7. Terminal part of a winter twig, natural si/.o. 8. Section of a winter twig showing a lateral bud and leaf -scar, enlarged. PLATE XXXIX. BIG SHELL-BARK HICKORY. 1. A flowering branch, x *. 2. A branch with fruit and a mature leaf, x J. 3. A nut, x i. 4. Cross-section of a nut, x J. 5. A winter twig, x 1. 6. Terminal part of a winter twig, slightly enlarged. 7. A leaf-scar with bundle-scars, slightly enlarged. 107 BIG SHELL-BARK HICKORY. Carya laciniosa, (Michaux f.) Loudon. FORM — In general it is the same as the Shell-bark (Carya ovata) except that it does not attain so large a diameter. When grown in a dense forest its trunk is very long, clean, and slightly tapering. BARK — Same as Shell-bark Hickory (Carya ovata) or probably somewhat less shaggy. TWIGS — Stout, usually a little velvety or tomentose, buff to nearly orange in color, covered with numerous rather inconspicuous longitudinally-elongated lenticels; pith angular. BUDS — Similar to those of the shell-bark (Carya ovata) except that they are a little larger and have less keeled and more hairy outer scales. LEAVES — Alternate, compound, with 7-9 leaflets, 10-22 inches long. Leaflets differ in size; basal pair smallest, about £ sixe of the terminal; the upper pair broadest between the middle and the apex. Leaflets sharp-pointed at apex, serrate on margin, tapering or rounded at base, thick, firm, dark green and smooth above, pale green to brownish and hairy below. Leaf-stalks grooved, stout, smooth or hairy, thickened at base, often persist for a long time. LEAF-SCARS — Alternate, more than 2-ranked, large, conspicuous, somewhat raised, heart-shaped or 3-lobed or inversely triangular or sometimes elliptical, containing numerous conspicuous bundle- scars which are distributed irregularly, grouped in 3 clusters or arranged in a curved line. FLOWERS — Similar to those of Shell-bark Hickory (Carya ovata). See page 106. FRUIT — Ovoid or broadly-oblong, 4-ribbed above the middle, covered with very thick husk which splits readily to the base. Nut dull white or yellowish, thick-walled, usually strongly pointed at both ends, containing a sweettj light brown and deeply lobed kernel. WOOD — Similar to that of the Shell-bark (Carya ovata), see page 10G. Lumbermen do not and manufacturers cannot distinguish between the wood of the two species. DISTINGUISHING CHARACTERISTICS— The Big Shell-bark Hickory, also known as Shag-bark Hickory and King Nut, is most closely related to the Shell-bark Hickory (Carya ovata). It can best be distinguished by its dull white or yellowish nuts which are usually strongly pointed at both ends, while those of the latter are white and barely tipped with a point and often rounded or notched at the base. The leaflets of this species number 7-9 to a leaf and are more downy on the lower surface than in Carya ovata which has only 5-7 leaflets to each leaf. For distinguishing char- acteristics between this species and other Hickories see "Distinguishing Characteristics" under Carya ovata, page 10G. RANGE — Central New York and Pennsylvania west to Iowa and Nebraska and south to Ten- nessee and Arkansas. DISTRIBUTION IN PENNSYLVANIA — Common in the southeastern part of the State. Most common east of the Allegheny mountains. Rare in the mountainous region except locally in the fertile valley between the mountains. Locally present in the western part. Probably most com- mon in Northampton, Bucks and Montgomery counties! HABITAT — Prefers wet, rich soil. Often found on situations which are temporarily flooded in spring. Frequent in rich bottomlands and on fertile hillsides. IMPORTANCE OF THE SPECIES — This is a very important species on account of the valuable wood and nuts which it produces. It is not very common in the State as a whole, but where it does occur it should be protected and regenerated as much as possible. Seeds should be planted rather than seedlings because the latter are sensitive to transplanting on account of their long taproot. 10S MOCKER NUT HICKORY. Carya alba, (Linnaeus) K. Koch. FORM— A large tree usually 50-75 ft. high with a diameter of about 2 ft. but may reach a height of 90 ft. with a diameter of 3 ft. Crown narrow oblong to broad round -topped. Trunk often swollen at base, in dense stands straight, clean, with little taper and free from branches for one- half of its height. BARK — Dark or light gray, i-3 of an inch thick, close, not shaggy nor smooth, roughened by irregular furrows which separate broad, flat, close, more or less scaly and rounded ridges. See Fig. 90. TWIGS — Compared with the other Hickories very stout, usually decidedly downy, reddish-brown, covered with numerous pale and longitudinally-elongated lenticels; pith angular. BUDS — Alternate, more than 2-ranked. Terminal bud very large, ovate, 2/5-4/5 of an inch long, densely hairy, usually blunt-pointed, covered with overlapping scales, the outer pair of which drops off in autumn and exposes the inner yellowish-gray silky scales. Lateral buds reddish- brown and do not split open very early. LEAVES — Alternate, compound with 7-9 leaflets, 8-12 inches long. Leaflets lanceolate-obovate, sharp-pointed at apex, toothed on margin, rounded or tapering at base, very fragrant, often downy on lower surface. Leaf -stalks hairy, flattened, grooved, and enlarged at base. Upper pair of leaflets largest with greatest width between the middle and the apex; lower pair often oblong- lanceolate. LEAF-SCARS— Similar to those of Shell-bark Hickory (Carya ovata). FLOWERS — Appear about May when the leaves are half developed. Staminate and pistillate flowers separate. Staminate borne in slender catkins 4-5 inches long, which are clustered in 3s en a common stalk. Pistillate borne in 2-5-flowered pale hairy spikes. FRUIT — Globular or ovoid, 1J-2J inches long, with a very thick or hard husk which splits to the middle or base. Nut globular, broAvnish, not evidently-flattened but 4-ridged towards apex, with a very thick shell and comparatively small and sweet kernel. WOOD — Similar to that of the Shell-bark Hickory (Carya ovata). See description page 106. Has a somewhat wider sapwood which is very white in color whence its specific name — alba. Heartwood dark brown. DISTINGUISHING CHARACTERISTICS— The Mocker Nut Hickory, also known as the Big Bud Hickory and the White-heart Hickory, can be distinguished from the two species of Shell- bark Hickory by its bark, which is rough and close and does not shag off, its stouter twigs, its scurfy pubescent foliage and its globular fruit which contains a globular brownish thick- shelled nut with a relatively small kernel. The buds are somewhat larger than those of the Shell- bark Hickories and thicker than the Pignut and Bitter Nut. The kernel of the latter two species is rfitterer and their leaflets are narrower and smoother. RANGE — Massachusetts and Ontario, west to Nebraska, and south to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA — Found most commonly in the rich valleys in the east- ern and southern parts of the State with local outposts in the central part. Also found in the hardwood forest region in the western part. HABITAT — Prefers rich, moist woods. Requires considerable moisture and sunlight. Does not thrive in shaded situations. Found "mainly in valleys and in fertile situations at the bottom of slopes. IMPORTANCE OF THE SPECIES — This species produces as valuable a wood as any of the Hickories. Some think that the wood is better than that produced by our other native Hickories because of the large amount of white sapwood. It is difllcult to transplant on account of its long taproot, hence it is advisable to plant the seeds rather than seedlings. Every effort which one puts forth in developing and perpetuating this species in our forests, especially in the farmer's woodlot, is justified. The fruit is large but the kernel is small and as a consequence It has no special market value. PLATE XL. MOCKER NUT HICKORY. 1. Branch with immature leaves and flowers, x J. 2. Branch with a mature leaf and fruit, x J. 3. A nut with husk removed, x J. 4. Longitudinal section of a nut, x 5. 5. A winter branchlet, x i. 6. A winter branchlet, slightly enlarged. 7. Section of winter branch, enlarged. 8. Section of winter branch enlarged PLATE XLI. PIGNUT HICKORY. 1. Branch with immature leaves and flowers, x i. 2. Branch with mature leaves and fruit with husk partly removed, x 3. A nut with husk removed, x J. 4. Cross-section of a nut, x i. 5. A winter brancn, x J. 6. Terminal section of a winter branch, enlarged. 7. A leaf-scar with bundle-scars, enlarged. 109 PIGNUT HICKORY. Carya glabra, (Miller) Spach. FORM — A fair-sized tree usually 50-GO ft. in height with a diameter of 2-3 ft., but may reach 11 height of 90 ft. with a diameter of 3-4 ft. Trunk slender, slightly-tapering, often clean and long. Crown oblong in shape, rather narrow, sometimes high, formed by short, spreading branches, the lower ones often drooping. BARK — Rarely peels off or exfoliates, is close, dark gray, shallowly -fissured, narrowly ridged, tough, J-l of an inch thick. Resembles the bark of the White Ash. See Fig. 89. TWIGS — Rather slender, usually smooth, at first yellowish-green, later reddish-brown, covered with numerous pale longitudinally-elongated Itmticels, roughened by leaf -scars and bud-scale scars; pith angular. BUDS — Alternate, more than 2-ranked, reddish-brown to gray, oval, blunt-pointed. Terminal bud 3-i of an inch long, larger than the laterals. All buds covered with reddish-brown, smooth, sharp-pointed, somewhat keeled outer scales and pale-silky inner scales. Outer scales often drop off during winter. LEAVES — Alternate, compound, with 5-7 leaflets, 8-12 inches long. Leaflets oblong to obovate- lanceolate, sharp-pointed at apex, finely toothed on margin, tapering or obliquely rounded at base, thick, smooth, dark green above, paler below. LEAF-SCARS — Alternate, heart-shaped or oblong or inversely triangular or 3-lobed, contain- ing numerous prominent bundle-scars irregularly scattered or arranged in a curved line or in 3 clusters. FLOWERS — Appear about May when leaves are about half developed. Staminate and pistillate flowers occur separately. Staminate in aments about 3-5 inches long and clustered in 3s on a common stalk. Pistillate in 2-5-flowered spikes on the new growth. FRUIT — Matures about October, variable in shape and size, pear-shaped or spherical to obovoid, 12 inches long, tapering at the base, reddish-brown, sometimes pubescent. Husk may remain closed or split open from apex towards the middle or occasionally along the entire length. Nut oblong to oval, with thick bony shell containing a kernel which is at first sweet, later bitter. WOOD— Similar to that of the other Hickories of the State, except the Bitter Nut Hickory. See description of wood page 106. DISTINGUISHING CHARACTERISTICS— The Pignut or Broom Hickory, also known as the Bitter Nut Hickory, can be distinguished by its smooth and rather slender twigs which bear small oval reddish-brown buds covered with scales, the outer hair of which is smooth or glandular dotted and often falls off before spring, thus exposing the inner velvety scales. Its buds are not yellow like those of the Bitter Nut Hickory and smaller than those of the other species of our native Hickories. The pear-shaped to ovoid fruit, with a thick bony-shelled nut is characteristic. The bark is close and does not exfoliate like that of the Shag-bark Hickory. The leaves, with 5-7 usually smooth and oblong to obovate-lanceolate leaflets, are distinctive. RANGE — Maine and Ontario west to Minnesota and Nebraska, and south to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA — Common in the southeastern and southwestern parts. Also fcund locally elsewhere. More common in the mountainous portion of the State than any other Hickory. HABITAT — Most common on dry ridges and hillsides. Rarer in swampy situations. Commonly scattered amidst our Oaks and Chestnut. Prefers plenty of sunlight. IMPORTANCE OF THE SPECIES — The Pignut Hickory produces a very valuable wood, espe- cially for the farmer. The fruit is not edible. It should be grown in the farmer's woodlot and in our larger forests in mixture with other species. The seedlings are difficult to transplant on account of their long taproots, which .are rather sensitive. In attempting to grow this species, one should plant the nuts and not the seedlings. The great value of its wood justifies every effort that one can put forth in growing it. 110 BITTER NUT HICKORY. Carya cordiformis, (Wangenheim) K. Koch. FORM — A rather large tree usually 50-75 ft. high with a diameter of 1-2 ft. but may reach a height of 100 ft. with a diameter of 21-3 feet. Trunk long, clean, with little taper. Crown round-topped, broadest near top, rather shallow in forest grown specimens. Lateral branches stout and ascending, often with semi-pendulous branchlets. BARK — Light gray, rather thin, roughened by shallow fissures and narrow ridges; tight- fitting and does not peel off or shag off 1n loos'? scales like the Shag-bark Hickory. See Fig. 91. TWIGS — Slender, smooth, glossy, often yellow-glandular and hairy towards apex, grayish or orange-brown or reddish, roughened with numerous pale and longitudinally-elongated lenticels: pith brown, angular. BUDS — Alternate, covered by 4 yellowish, glandular-dotted scales occurring in valvate pairs. Terminal bud evidently-elongated, flattened, blunt" -pointed. Lateral buds usually superposed; the lowest or axillary one usually small and sharp-pointed; the upper one larger, evidently- stalked and angular. LEAVES — Alternate, compound, with 7-11 leaflets, 6-10 inches long. Leaflets lanceolate to ovate-lanceolate, lateral ones sessile, sharp-pointed at apex, finely toothed on margin, obliquely tapering or heart-shaped at base; when mature dark yellowish-green above, paler below. LEAF-SCARS — Alternate, large, conspicuous, raised, heart-shaped, triangular to elliptical, lighter than twigs, containing numerous bundle-scars arranged in 3 groups or in a single curved line or occasionally scattered irregularly over whole scar. FLOWERS — Appear about May when leave? are half-developed. Staminate and pistillate flowers separate. Staminate green and arranged in triple-clustered aments about 3-4 inches long. Pistillate, and small clusters on the new giowth about J of an inch long, somewhat angled and scurfy -hairy. FRUIT — Matures about October; spherical to obovate about S-1J Inches long. Husk thin, 'yellowish glandular-dotted, splits open to about the middle into four valves; before splitting appears 4-winged from apex to about the middle. Nut thin-shelled, at least as broad as long, smooth, short-pointed, with reddish-brown and very bitter kernel. WOOD — Wood of this species resembles the wood of the other Hickories, described on' page 106, only it is somewhat lighter, not quite so strong, of somewhat less fuel value, more brittle, less stiff, and yields more ash when burned. DISTINGUISHING CHARACTERISTICS— The Bitter Nut Hickory, also known as Swamp Hickory and Bitter Hickory, can be distinguished by its lanceolate leaflets which are pube- scent beneath, and smaller than those of any other native Hickory. It is the only native species which has yellow buds with 4-6 bud-scales arranged in valvate pairs. Its terminal buds are flattened and elongated while the lateral buds are evidently-stalked and superposed. The nut is globular, short-pointed, thin-walled, containing a bitter kernel, and is covered by a thin husk which in time splits open from the apex to about the middle. The bark is rough, but does not scale off, which characteristic it has in common with the Pignut and the Mocker Nut. RANGE — Quebec to Minnesota and Nebraska and south to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA— Local throughout the southeastern and southern parts. Also reported from the central and northern parts. Nowhere common. Usually solitary and scattered, HABITAT — Prefers low, wet, and fertile situations such as border of streams and farmers' woodlots located in rich agricultural regions. Often found, however, far up the slopes of moun- tains. It ascends to the top of the South Mountains in Pennsylvania. Not very tolerant of shade. IMPORTANCE OF THE SPECIES — This species produces valuable wood but its fruit Is not edible. It grows best on rich moist coil such as one usually finds, in a farmer's woodlot. It endures transplanting better and grows more rapidly than any other of our Hickories. This valuable wood is becoming rare. A future supply should be insured by developing this tree in mixture with others in the farmer's woodlot and in fertile portions of larger forests. It is not gregarious but prefers to* grow as a single specimen in mixture with other species. PLATE XLII. BITTER NUT HICKORY. 1. Branch with immature leaves and flowers, x J. 2. Branch with a mature leaf and fruit, x J. 3. A fruit with husk partly opened, x i. 4. A nut with husk removed, x |. 5. Longitudinal section of nut, x i. 6. A winter branch, x J. 7. Section of winter branch showing superposed buds, slightly enlarged. 8. Section of winter branch showing superposed buds and leaf-scar, slightly enlarged. 9. A leaf -scar with bundle-scars, enlarged. Ill THE BIRCH FAMILY— BETULAOEAE. The Birch family comprises 6 genera with about 75 species of trees and shrubs which are confined to the colder part of the northern hemisphere. Of this number 5 genera with about 30 species are native to North America and 5 genera with 11 species to Pennsylva- nia. All the members of this family, even though they may belong to different genera, have many morphological features in common. The leaves are simple, alternate, borne singly or in pairs on the branches but never opposite each other. The staminate and pistillate flow- ers are separate, but are borne on different parts of the same tree and usually on different parts of the same branch. The staminate flowers are long, usually in drooping aments, or in spike-like or knob- like aments and may be with or without a perianth. The fruits are small, one-celled, usually subtended by a large bract which in the most important genera develops into a cone-like structure called a strobile. Various products of high commercial importance are produced by this family. The wood of the Birches is used extensively for furni- ture, flooring, interior finishing and has a very high fuel value. The fruit of the Hazelnuts is prized as food. The wood of some of the Alders is especially adapted to the manufacture of gunpowder and charcoal. The bark of the Black Birch yields a volatile oil of consid- erable importance. The technical value of the products from the members of this family are becoming more important every year. The wood of some of the species which was despised formerly, is now considered of high value in some particular industries, on account of the new uses to which it is being put. The science of Xylology, which is merely in its formative period, will do much in advancing the position of the wood of species at present despised or at least not fully known. The subjoined key will aid in distinguishing the genera of this family. KEY TO THE GENERA. Page. 1. Staminate flowers solitary on each bract; pistillate flowers with a perianth; fruit not a strobile, 2 1. Staminate flowers 2 to several on each bract; pistillate flowers without a perianth; fruit a stvobile 4 2. Shrubs: twitf* <-ovrml with stiff red hnirs standing out at right angles; nuts large covered by leaf-like involucre, Corylus 122 2. Trees: Twigs not covered with stiff red hairs; nuts small and subtended by a large bract 3 3. I'.;irk close, smooth and tinted; nut subtended by a flat 3-lohed bract, terminal lobe serrate on one side, Caxpinus 120 3. Bark thin covered by loose ribbon-like narrow brown scales; nut subtended by a closed bract arranged in hop-like clusters, Ostrya 119 4. Shrub with close, somewhat fluted bark; wood yellowish upon exposure; buds stalked, obtuse at apex, covered with two exposed valvate scales; fruit woody and persistent Alnus 121 4. Small to large trees with loose bark usually peeling off into thin film-like layers; buds not stalked, acute at apex, covered with 3 or more overlapping scales; fruit membranous and deciduous, Betula 112 112 THE BIRCHES— BETULA, Tournefort (L.) This genus comprises about 35 known species, of which number 25 are trees and the others shrubs. Of the known species about 15 are native to North America and 5 to Pennsylvania. The members of this genus are without exception called Birches. In most of them the bark of the trees when young is smooth and peels off into film-like papery layers which vary in color according to the species from chalky white to reddish-brown. A few species have, however, a close and smooth bark which does not peel off into thin film-like papery layers. The wood is dense and hard, does not show the annual rings very clearly, is of high fuel value and usually reddish-brown in color, sometimes possessing a highly prized curly or wavy figure. The twigs of the season produce only one leaf at a point, while the twigs of the previous season produce two leaves from the lateral buds situate on the short spur-like branches. The leaves are simple, always alternate, occur singly or in pairs but never op- posite. The flowers appear before or with the developing leaves. The staminate flowers appear clustered in long tassel-like bodies hanging down from the end of the twigs and are known as aments. The pis- tillate flowers appear below the staminate and are nearly erect, rather small and slender. The fruit is a cone-like structure known as a strobile consisting of a central axis to which numerous scales are attached. The scales are thin, 3-lobed, and bear the small flat nuts with their wings. The nuts are very light and easily scattered by the wind for considerable distances from the mother or seed trees. The commercial products derived from some of the members of this genus are rather important and valuable. The species found in the eastern part of North America yield products of more value than those found in the western part. Most of the species found in the western part of North America are too small, or infrequent in the form of stands, to be commercially important for general or even domestic use. Some of the species found in the eastern part of North America are also small shrubs but others reach the size of large tim- ber trees which yield not only excellent wood but also valuable oils, flavors, and bark. The subjoined key will aid in distinguishing the species of Birch found in Pennsylvania. Separate summer and winter keys were not developed since the following key is based primarily upon bark char- acteristics which are present at all seasons of the year. 113 KEY TO THE SPECIES. Page. 1, Bark usually separating into thin film-like papery layers 2 1. Bark close, not separating into thin film-like papery layers, 4 2. Outer bark white in color, B. alba var. papyrif(&ra 114 2. Outer bark not white in color 3 3. Outer bark yellow in color; strobiles usually sessile; leaves usually rounded at base, B. lutea 115 3. Outer bark reddish-brown, close, inner bark tinged with red; strobiles slender- stalked; leaves usually wedge-shaped at base, B. nigra 116 4. Bark chalky white covered with black triangular spots below insertion of lateral branches; small tree, often in clumps; leaves long-acuminate, B. populifolia 117 4. Bark dark reddish -brown; large tree, usually occurs singly; leaves ovate with acute apex; twigs and inner bark with wintergreen like taste B. lenta 118 in PAPER BIRCH. Betula alba var. papyrifera, (Marshall) Spach. FORM — A large tree usually attaining a height of 50-75 ft. with a diameter of 1-2 ft., but may roach a height of 80 ft. with a diameter of 3 feet. Trunk in open grown trees short and covered nearly to the base with lateral, often ascending branches; in close stands branchless below and bearing a narrow open head. BARK — On trunk and older branches chalky to creamy white and peeling off in thin film- like layers which are tinged with yellow and covered with horizontally-elongated lenticels. On older trunks rough and often fissured into irregular thick scales. TWIGS — Rather stout, somewhat viscid, decidedly hairy, at first greenish, later becoming smooth, reddish-brown, and arter several years, bright white, like the trunk, covered with pale, horizontally-elongated, orange-colored lenticels. BUDS — Alternate, ovate, sharp-pointed, divergent, about J of an inch long, dark chestnut- brown in color, covered by a few overlapping bud-scales with downy margins. LEAVES — Alternate, simple, ovate, 2-3 inches long, 1J-2 inches wide, rather firm in texture; upper surface darti green, under surface light green; narrowed or rounded at the base, sharply toothed on the margin and sharp-pointed at the apex. LEAF-SCARS — See "Leaf-Scars" under Black Birch, page 118. FLOWERS — Appear in April or May bef&re the leaves. The staminate are arranged in aments, which occur in groups of 2-3 .and are about J to li inches long, becoming 3}-4 inches long in spring. The pistillate havo light green lanceolate scales and bright red styles, and are arranged in clusters about 1-11 • inches long. FRUIT— A cylindrical, short-stalked strobile about 15 inches long. Scales long, with thick lateral lobes and a rather long terminal lobe. Seeds small and winged. Wings wider than the nut. WOOD — Diffuse-porous; rays small and inconspicuous; light, strong, hard, light brown tinged with red, with rather thick, light sapwood. Weighs 37.11 Ibs. per cubic foot. Used exten- sively for spools, shoe lasts, pegs, fuel, and in the manufacture of paper pulp. DISTINGUISHING CHARACTERISTICS — The Paper Birch, also known as Canoe Birch and White Birch, may readily be distinguished from all the other species of Birch in Pennsyl- vania except the Gray Birch, by its characteristic white bark, which is never renewed when once removed. The European White Birch, which is introduced extensively for ornamental pur- poses, also has a white bark. To distinguish it from the Gray Birch see "Distinguishing Characteristics" under Gray Birch. RANGE — From Newfoundland to Alaska, south to Pennsylvania, Michigan, Colorado, and Washington. This is one of the few transcontinental species. DISTRIBUTION IN PENNSYLVANIA — Found only in the northern part of the State. Com- mon but scattered in Tioga and adjoining counties. HABITAT — Usually found on rich wooded slopes and on the borders of lakes, swamps, and streams; also scattered through the forests of other hardwoods and occasionally through coniferous forests. IMPORTANCE OF THE SPECIES — This species is commercially of little importance in Pennsylvania on account, of its limited distribution. It is not of sufficient importance to Justify its artificial propagation, but wherever it occurs naturally it should be protected so as to insure an abundant future growth. The wood is sufficiently prized to justify its conservative utilization, and also its protection, where nature produces it gratuitously. PLATE XLIII. PAPER BIRCH. 1. Flowering branch with immature leaves, (s) staminate flowers, (p) pistillate flowers, x J. 2. Branch with mature leaves, fruiting strobiles, and partly developed staminate aments, x J 3. A winged seed, enlarged. 4. A strobile scale, enlarged. o. A winter branch with 3 partly developed terminal staminate aments, x J. 6. Section of a lateral winter spur-branch, enlarged, t. Section of a terminal winter branch, enlarged. PLATE XLIV. YELLOW BIRCH. 1 Flviwering branch with (s) staminatc flowers, and (p) pistillate flowers, x 2. Branch with mature leaves and four fruiting strobiles, x J. 3. A winged seed, enlarged. 4. A strobile scale, enlarged. 5. Winter branch with partly developed terminal staminate amenta, x 1. 6. Section of a lateral winter twig, enlarged. 7. Section of a terminal winter twig, enlarged. 115 YELLOW BIRCH. Betula lutea, Michaux. FORM— A large tree usually attaining a height of 60-80 ft. with a diameter of 2-3 ft., but may reach a maximum height of 100 ft. with a diameter of 3-4J feet. Trunk in the open usually short, branching near the base; its long slender branches forming a wide open rather hemispherical crown, in close stands often rather free from lateral branches. BARK — Close and furrowed or peeling off in thin yellow film-like papery scales. Varies with the age and location of the tree. On young trunks and branches rather close, shining, yellow but soon forming a ragged fringe, later peeling off into thin, yellow, film-like, papery layers. On old trunks it finally becomes reddish-brown and roughened with fissures. The ragged bark is often pulled off and used by campers to start fires in wet weather. See Fig. 68. TWIGS — At first green and hairy, later brown and smooth, finally dull silvery-gray. Terminal twigs long and slender; lateral short nnd stout; usually covered with elongated horizontal lenticels which in time unite to form a long horizontal line. BUDS — Similar to those of the Black Birch, but sometimes slightly more downy. See page 118. LEAVES — Alternate, simple, occur singly or in pairs but never opposite, 3-4 inches long, ovate, wedge-shaped or heart-shaped at base, doubly serrate on margin, acute at apex, dull green above, yellowish-green below. LEAF-SCARS — Similar to those of the Black Birch in particular, and all of the other Birches in general. FLOWERS — Appear about April before the leaves. Staminate- and pistillate separate, but usually on the same branch. Staminate are formed in the fall, remaining over winter as aments about 1 of an inch long which elongate to about 3 inches in spring. Pistillate about $ of an inch long, with acute scales which .are light red and hairy above, and green below. FRUIT — Ail erect, usually very short-stalke-1 strobile, about 1-11 inches long, ovate in out- line, consisting of numerous 3-lobed scales fastened to a central axis and bearing small winged nuts with rather narrow wings. WOOD — Diffuse-porous; rays indistinct; heavy, hard, strong, compact, not durable when in contact with the soil. Heart-wood light brown, tinged with red; sap-wood pale in color. Weighs 40.8-t pounds per cubic foot. Used fo* furniture, flooring, interior finish, boxes, certain veneers and fuel. DISTINGUISHING CHARACTERISTICS— The Yellow Birch, also known as Silver and Gray Birch, can readily be distinguished from the other Birches of Pennsylvania by its yellow bark which peels off into thin, film-like, papery scales. Its method of peeling the bark resembles that of the Paper Birch and the lied Birch, but it does not have the white color of the former nor the reddish to greenish -brown color of the latter. The loose, film-like, papery scales of the Red Birch are smaller than those of the Yellow Birch and the strobiles of the former are slender-stalked while those of the latter are usually sessile or very short-stalked. RANGE — Newfoundland, south to Pennsylvania, and along the mountains to North Carolina and Tennessee, west to Minnesota. DISTRIBUTION IN PENNSYLVANIA— Found locally throughout the State but most common in the Alleghenies. HABITAT — Common on moist rich uplands, borders of streams, and in swamps. IMPORTANCE OF THE SPECIES— The Yellow Birch is one of the largest deciduous trees of northeastern America. Until recently the value of its wood was not fully appreciated, but today it holds a fair position on the lumber market and in the future it will no doubt attain a still better position. It has been classed as one of the most artistic, reliable, and versatile of the hardwoods of this country. With all its good qualities, it has superior associates and consequently cannot be recommended for forestry purposes except on the farmer's woodlot where fuel is especially desired and in such other places where it comes up naturally and other more desired species will not grow to advantage. 116 RED BIRCH. Betula nigra, Linnaeus. FORM — A medium-sii.ed tree usually attaining a height of 30-50 ft. with a diameter of 1-2 ft., but may reach a height of 100 ft. witu a diameter of 5 feet. Trunk usually short and divided near the base into a few slightly diverging limbs. Crown rather narrow, oblong, and irregular. BARK — Varies with the age of the tree and its location on the trunk. On lower part of old trunks dark reddish-brown and roughened by fissures which separate irregular scales. On younger trunks and upper portion of older ones peels off into thin, film-like, papery scales which are reddish-brown to greenish-brown in color and persist for a few years during which time they form a ragged fringe and expose the light red and close bark underneath. See Fig. 65. TWIGS — Slender, at first hairy and greenish, later smooth, reddish-brown, covered by pale horizontally-elongated lenticels. BUDS — Alternate, ovate, sharp-pointed, shining, smooth or slightly hairy, covered withj usually 3-7 chestnut-brown overlapping scales. LEAVES — Alternate, simple, broadly cvate, 1J-3 inches long, wedge-shaped at base, acute at apex, doubly-serrate ou margin, deep green above, pale yellowish-green below. LEAF-SCARS— Similar to those of th<* Black Birch. See page 118. FLOWERS — Appear about April before the leaves. Staminate and pistillate separate, but usually on the same branch. Staminate formed in the fall, remaining over winter as aments about 3 of an inch long, usually in clusters of three, which elongate to about 2-3 inches the following spring. Pistillate about $ of an inch long, developing in spring from buds situate below the staininate flowers. FRUIT — An erect, slender-stalked, pubescent, cylindrical strobile, 1-1* inches long, consisting of numerous 3-lobed pubescent scales fastened to central axis and bearing small, hairy, winged nuts. Terminal lobe of the scales is larger than the laterals. WOOD — Diffuse-porous; ,rays indistinct; light, scft, strong, with light-brown heartwood and pale thin sapwood. Weighs 35.91 pounds per cubic foot. Used in the manufacture of furniture, slack-cooperage, fruit and vegetable baskets, wooden ware, and turnery. DISTINGUISHING CHARACTERISTICS— The Red Birch, also known as the River Birch, can be recognized by its reddish-brown to cinnamon-red bark which peels off into film-like papery scales. The layers are smaller and less ragged than those of the Yellow Birch which has a decidedly yellow ir silvery-yellow colored bark. The Black Birch has a closer bark which does not peel off and the other species of Pennsylvania have a white bark. The River Birch is usually found along streams or in other wet locations which may also aid in dis- tinguishing it. RANGE — Massachusetts south to Florida, west to Minnesota, Kansas and Texas. DISTRIBUTION IN PENNSYLVANIA— Found throughout the State along the banks of the principal rivers and their chief tributaries. HABITAT — Prefers the banks of streams, lakes, pools, and swamps. Occasionally found upon drier locations. It is called River Birch because it is usually found along the banks of rivers or other locations having similar moisture conditions. IMPORTANCE OF THE SPECIES— The Red Birch is of little commercial importance in Pennsyl- vania as a lumber species on account of the relatively small size which it attains, the softness of Its wood, and the absence of figure and attractive color in the wood as well as its limited distribution. It is esreiitially a southern species reaching its optimum development in North Carolina and adjoining states. While it is of little commercial importance it may be of economic importance in such situations where moisture-loving trees are required to bind soil, as along streams, or where it is desirable to establish stands in extremely swampy locations. It is attract- ive as an ornamental tree. PLATE XLV. RED BIRCH. 2' SnWe.1. Fruit of Beaked Hazelnut (Corylus rostrata), x J. PLATE LII. BEECH. 1. Branch with staminate and pistillate flowers and immature leaves, ed. 1. 2. A staminate flower, enlarged 3. A pistillate flower, enlarged. 4. A branch with mature leaves and three fruits, x 4. 5. A seed, natural size. 6. A winter branch witb long, slender, and sharp pointed buds, x J. 7. Terminal section of a winter branch with long, slender, and sharp pointed bud covered with many overlapping scales, slightly enlarged. 123 BEECH. Fagus grandifolia, Ehrhart. FORM — Large tree usually attaining a heigh't of 50-60 ft. with a diameter of 2-3 ft., but may reach a height of 125 ft. Avith a diameter of 4J feet. Forest grown trees tall, slender, free from lateral branches for a considerable distance from the base, with a rather compact shallow crown. Open grown trees short-trunked, covered with many lateral branches which are often drooping below and erect above, forming a dense, deep, symmetrical crown. BARK — Very close, smooth, light gray, mottled with dark spots. It invites the cutting of initials and other outline carvings. See Fig. 92. TWIGS— Slender, da;lc yellow to gray, at first hairy, later smooth, zigzag, covered with yellowish lenticels, and marked by Dud-scale scars. BUDS — Alternate; terminal bud present; five times as long as wide, slender, sharp-pointed, conical, usually smooth, covered by 10-20 reddish-brown bud-scales with hairy margins. - LEAVES — Alternate, simple, ovate, 3-4 inches long, stiff leathery, with tapering apex and sharp-toothed margin; light green above, yellowish-green below. LEAF-SCARS — Raised, crescent-shaped to elliptical with a few scattered bundle-scajrs. Stipule-scars narrow, almost encircling twig; one end of each stipule-scar is raised above the other end. FLOWERS — Appear about April when leaves are one-third developed. Staminate flowers in a stalked round head about one inch in diameter; pistillate flowers in 2-flowered clusters from the axil of the upper leaves. 1RUIT — A stalked, prickly, 4-valved bur containing triangular pale brown, shining nuts with sweet edible kernel. WOOD — Diffuse-porous with minute pares; broad medullary rays present with narrow ones intervening; hard, strong, tough, not durable, difficult to season, light red in color. Weighs 42. N'.» ii)s. per cubic foot. Used for rail'.ond ties, parquet flooring, novelty wares, carpenter tools, fuel, and charcoal. DISTINGUISHING CHARACTERISTICS— The American Beech can readily be distinguished by its close, smooth, light gray bark, its simple, leathery, often persistent leaves, its prickly gnd stalked fruit with triangular seeds, and its long, slender, conical, sharp-pointed reddish- brown buds. RANGE — Nova Scotia to Ontario and Wisconsin, south to Florida and Texas. DISTRIBUTION K7 PENNSYLVANIA— Found in every part of the State, but most abundant in the northern parr. Local in the southeastern and southwestern parts. HABITAT — Commonly found on rich moiet bottom lands, but is also abundant on gravelly slopes and rich uplands. It endures dense shade and variations of temperature. IMPORTANCE OF THE SPECIES — This species was formerly not of very much commercial importance, but it is now becoming more important since the process of timber impregnation has been developed. It furnishes excellent fuel and in some regions it is now converted into railroad ties and aloO manufactured into various by-products on a rather extensive scale. It cannot, however, be recommended for extensive planting for forestry purposes but should be retained and developed in the farmer's woodlot where the production of fuel is important. In the future when more intensive systems of forest management have been developed it can be used for undei planting and as a noil conserver. 124: THE BEECH FAMILY— FAGACEAE. The Beech family contains some of the most important timber spe- cies and has its representatives distributed in nearly all regions of the world. The Pine family alone surpasses this one in economic im- portance. It yields not only high grade wood but also food in the form of nuts, tanning and dyeing materials, and cork. The wood is of a high grade and used extensively. The members of the Beech family have alternate, simple, pinnately- veined, mostly deciduous leaves. A division of the family known as the Live Oaks retains its leaves during the winter. The flowers, staminate and pistillate, which are rather inconspicuous, are usually yellowish to greenish in color and found on different parts of the same tree and usually on different parts of the same branch. The inconspicuous flowers of this family stand in strong contrast with the conspicuous flowers of such species as the Magnolias, Cherries, Apples, Papaw, and other broad-leaved trees. The fruit consists of one or more one-seeded nuts covered by an outer cartilaginous and an inner membranous covering. It is usually heavy and in some species matures in one season while in others it requires two seasons. On account of the heavy weight of the seeds they usually fall im- mediately below the tree and remain there unless disseminated by animals, birds, water, or gravity on slopes. The seed fills the entire cavity of the nut. This family consists of 6 genera and about 400 species of trees and &hrubs of which number 5 genera with about 60 species occur in North America and 3 genera with 19 species in Pennsylvania. The 3 genera not found in Pennsylvania are Castanopsis, Pasania, and Nothofagus. Representatives of the first 2 genera are found in the western part of the United States, while the genus Nothofagus is confined to the southern hemisphere. The subjoined key will distinguish the 3 genera found in Pennsylvania. KEY TO THE GENERA. Page. 1. Staminate aments in globose heads; nuts triangular; buds long, slender, sharp- pointed, conical, 5 times as long as wide, Fagus 125 1. Staminate aments elongated, slender; nuts not triangular; buds shorter, stout, dull-pointed, not 5 times as long as wide 2 < 2. Staminate aments erect or ascending; nuts enclosed in a prickly bur; buds covered with a few ovei lapping scales, terminal ones absent Castanea 125 2. Staminate aments drooping; nuts seated in an open scaly cup; buds covered with many pverlaoping scairs and clustered a( the terminal end of twigt , , .Quercus 128 125 BEECH— PAGUS, (Tourn.) L. This genus comprises trees with a close, smooth and grayish bark, a light horizontal spray, simple straight-veined leaves, hard and dif- fuse-porous wood and long, slender, conical, sharp-pointed buds. The members of this genus are limited to the northern hemisphere with only 1 native representative in America and 4 in the eastern hemis- phere. One of the latter is widely distributed in Europe and south- western Asia. It is the Beech which figures in ancient literature and is -now known as the European Beech (Fagus sylvatica L.). This species is now planted extensively for ornamental purposes in America, especially 3 varieties of it, with purple leaves, cut leaves, and pendant branches respectively. The wood of the European Beech is used extensively in France and Germany for lumber and fuel and the nuts are used to feed swine. The nuts also yield a valuable oil. The other species of the eastern hemisphere are found in east- ern Asia. The description of the sole native American representa- tive, found on page 123, will suffice for the genus. CHESTNUT— CASTANEA, (Tourn.) Hill. This genus comprises 5 species of trees and shrubs with furrowed bark, round branchlets without terminal buds, ring-porous wood which is rich in tannin and durable in contact with the soil. The leaves are simple, alternate, stiff, sharp-toothed, and straight-veined. The members of this genus blossom in summer and mature their fruit the same autumn at about the time when the first frost ap- pears. The fruit consists of a large spiny bur in which 1-5 nuts are borne. The nuts are highly prized as food. Three species of Chest- nuts are cultivated in this country for their fruit, the American, the European, and the Japanese. The Chestnuts are confined to the northern hemisphere, both eastern and western. No representatives of this genus are at present found in the western part of North America, but records show that the Chestnut was at one time indi- genous to this region. Three species are native in eastern North America, 2 of which attain tree-size, while 1 (Castanea alnifolia, Nutt.) seldom exceeds 3 ft. in height and is found in the south Atlantic states. The subjoined key will aid in identifying the two species native to Pennsylvania. KEY TO THE SPECIES. Page. 1. Large trees; leaves oblong-lanceolate, smooth and green on both sides; nuts 1-5, usually 2-3, in a bur; buds } of an inch long covered by smooth chestnut-brown scales, C. dentata 126 1. Small trees or shiubs; leaves oblong, whitish downy beneath; nuts rounded, usually one in a bur; buds J of an inch long, covered by scurfy red scales, C. pumila 127 126 CHESTNUT. Castanea dentata, (Marshall) Borkhausen. FORM — A large tree usually attaining a height of 60-80 ft. with a diameter of 3-4 ft., but may roach a height of over 100 ft. with a diameter of 10 feet. A tree with a diameter of 17 ft. has been recorded from Francis Cove, western North Carolina. Open grown trees have short trunks with deep, widespreading crowns. Trees in close stands tall, with little stem taper aiyl few lateral branches. BARK — On old trunks fibrous, deeply fissured; fissures separate somewhat oblique ridges which are covered wit'i dark brown scales. On young trunks and older branches much smoother. See Fig. 82. TWIGS — Stout, smootli, greenish to brown, round or angular, swollen at the nodes; covered with numerous small, white, raised lenticels. Pith star-shaped. BUDS — Alternate, axillary; terminal bud absent; ovoid, } of an inch long, sharp to blunt-pointed; covered by 2-3 dark chestnut-brown scales. LEAVES — Alternate, simple, oblong -lanceolate, sharp-pointed at apex, toothed on margin, smooth on both lowtr and upper sides. LEAF-SCARS — Semi-oval in outline; raised from twig; with numerous, rather inconspicuous, scattered, occasionally clustered bundle-scars. FLOWERS — Appear in June or July. Stamina te in crowded clusters along ament; pistillate appear at base of upper aments as globular involucres. FRUIT — Matures in September or October. A bur covered with numerous, prickly spines and containing 1-5, usually 2-3 nuts. WOOD — Distinctly ring-porous; with indistinct medullary rays; quite strong in young trees, rather weak in older ones; yellowish-brown, very durable, splits easily, rich in tannic acid. Weighs 28.07 Ibs. per cubic foot. Used for railroad ties, telegraph poles, fence posts, rails, cheap furniture, and tacnic acid. DISTINGUISHING CHARACTERISTICS— The Chestnut can readily be distinguished from all other trees except the Chinquapin by its characteristic fruit. See "Distinguishing Characteristics," under Chinquapin, page 127. For Genus Description and Key to Species, see page 125. RANGE — Maine to Michigan, south to Delaware and along the mountains to Alabama, Mis- sissippi, and Arkansas. DISTRIBUTION IN PENNSYLVANIA — Very common in the eastern, southern and central parts and locally in other parts. It is the most common tree of Pennsylvania. HABITAT — Grows almost on any kind of soil, from bottom lands to mountain tops, but does not love limestone or extremely wet soil. In the North it is common on glacial drift but in the South it remains close to mountains and reaches its best development in 'western North Carolina and eastern Tennessee. IMPORTANCE OF THE SPECIES— This species, which reproduces itself best by sprout, but &lso by seed and seedling, is one of the most important commercial species in this State. It has shown itself to be the surest of all our trees to reproduce a stand fully from sprout. It grows fast and is usec1 for many purposes in small as well as large sizes, and thus can be managed in short rotation, which insures a certain profit on the investment. A Chestnut forest managed for tl>e purpose of producing telegraph poles should be run on rotations of about 55 years. On poor soil it may be necessary to increase the length of the rotation. Good tendance reduces the. length of the rotation while the absence of it will not only increase the length but also result in an inferior grade of wood. The great variety of uses to which the wcod of this species is put will drain the existing forest to an enormous extent. There is urgent need to reproduce, develop, and improve our existing stands and also to guard against such destructive organic enemies «s the Chestnut Bark Disease (Endothia gyrosa var. parasitica) commonly known as the Chestnut Blight. PLATE LIII. CHESTNUT. 1. Branch with staminate and pistillate flowers and mature leaves, x ?.. 2. A staminate flower, enlarged. 3. A pistillate flower, enlarged. •1. A branch with a cluster of closed and open burs, x J. 5. A nut, x J. 6. A winter branch, x J. 7. A section of winter branch, enlarged. PLATE LIV. CHINQUAPIN. 1. A flowering branch with leaves, x J. 2. A fruiting brniu'h with mature leaves, x A 3. A nut, x i. 4. A winter brand), x J. 6. A section of winter branch, enlarged. 127 CHINQUAPIN. Castanea pumila, (Linnaeus) Miller. FORM — A small tree or shrub usually attaining a height of 20-30 ft., but may reach a height of 50 ft. with a diameter of 3 feet. In Pennsylvania seldom exceeds 20 ft. in height and often is only 3-5 ft. in height. This is the northern limit of its distribution. Trunk usually short and crown roundish. BARK — May attain a thickness of one inch, usually fissured and broken into light reddish- brown loose plate-like scales. On branches and young trunks rather smooth, dark grayish-brown. TWIGS — Slender, at first pale woolly, later pubescent, finally smoother, reddish-brown to dark brown; covered with numerous leuticels. BUDS — Alternate, axillary; terminal bud absent; ovoid, blunt-pointed, about J of an inch long; covered with scurfy red scales. LEAVES — Alternate, simple, oblong, thick, firm, straight-veined, sharp-pointed at apex, sharply toothed on margin, yellowish -green and smooth on upper surface, pale green and whitish-downy beneath. LEAF-SCARS — Semi-oval, somewhat raised; Avith scattered, occasionally clustered, rather inconspicuous bundle-scars. FLOWERS — Appear in May or June in more or less spreading aments. Stamiaate occur In crowded clusters along ament; pistillate at base of upper aments in ovoid, prickly involucres. FRUIT — Matures in September or October. A bur covered with numerous stiff spines and containing usually 1, seldom 2, ovoid bright brown and sweet nuts with a more> or less hairy apex. WOOD — Ring-porous; with indistinct medullary rays; hard, strong, brown, durable, rich In tannir acid; splits easily. Weighs about 28 Ibs. per cubic foot. Used for fence posts, rails, and railroad ties. DISTINGUISHING CHARACTERISTICS— The Chinquapin is a little brother of the Chestnut which one may see by comparing their characteristic fruit. It can be distinguished from the Chestnut by its smallor size, its whitish down on lower surface of leaf-blades, its smaller scurfy red buds, and smaller burs containing usually 1 nut. RANGE — New Jersey and Pennsylvania to Florida, Missouri, and Texas. DISTRIBUTION IN PENNSYLVANIA— Locally in a few counties in the southern part of the State. Known to occur in the counties of Franklin, Adams, York, Lancaster, and Chester. HABITAT — Usually found on dry, sandy slopes, rather fertile hillsides, and margins of ponds and streams. IMPORTANCE OF THE SPECIES— It is of no commercial importance in this State on account of its small size and its limited distribution. It is very attractive as an ornamental shrub and yields delicious nuts. 128 THE OAKS— QUEKCUS, (Tourn.) L. This genus, which consists almost entirely of trees, comprises about 300 species in the world. The Oaks are world famous on account of their wide distribution, physical sturdiness, great strength, and the high commercial value of their wood. Most of them attain a great age and are aggressive competitors in the constant struggle which is going on in the forest. They can be reproduced by sprouts or by seed, naturally or artificially. Their modesty recommends them from a silvicultural point of view since they will grow in habi- tats which are moist or dry, sterile or fertile, cold, temperate or tropical, at low altitudes or at high altitudes up to the timber line. They prefer the temperate climate. Economically this genus is one of the most important among the trees. Its wood is used extensively and is especially adapted for high grade work. The bark is rich in tannin, while that of a few European species is used for cork. The galls which are caused by insect stings are also often rich in tannin. The nuts are used in some places as food for man and swine, and occasionally when roasted form a substitute for coffee. The leaves are alternate, simple, and usually shed in autumn. A division of the Oaks known as the Evergreen or Live Oaks, sheds the leaves at the end of the second or third season. The flowers, staminate and pistillate, appear on different parts of the same tree and often on different parts of the same branch. The staminate or male flowers are small and arranged singly on a long slender and drooping ament which emerges from the buds on the twigs of the previous year's growth. The pistillate or female flowers are small, inconspicuous, urn-like bodies which appear singly or in groups from the base of the developing leaves of the season. The flowers are fertilized by the wind and develop into a nut-like fruit known as an acorn. The fruit is distinctive in having a scaly, often bristly cup separated from the thin-shelled nut which it partly or almost wholly encloses. In autumn the nuts may fall to the ground while the cups persist on the tree, or the nut and cup may fall together. The acorns may germinate immediately after falling to the ground, but usually they remain dormant until the following spring. The seed-leaves of the nut remain in the shell and furnish nourishment to the developing seedling. A long tap root is characteristic of an oak seedling. This makes them difficult to transplant in a nursery or to plant in the place where they are to develop into large trees. A large part of the first two seasons' growth of many of our Oaks is concentrated mostly in the development of a root system. The 129 acorns are heavy and disseminated mainly by water, mammals, birds, and gravity on slopes. The fruit of some Oaks matures in one season, while others require two seasons. At the end of the first season the latter appear as immature acorns. The mature fruit of the annual fruiting Oaks is attached to the growth of the season, while that of the biennial fruiting Oaks is attached to last season's growth. Dur- ing the winter season, immature acorns of the biennial fruiting Oaks are found on the growth of the previous season. The Oaks of Penn- sylvania may be classified in two groups: A. Acorns mature in one season; leaves with rounded lobes, not bristle-pointed; shell of nut usually smooth inside; kernel usually sweet; bark pale often scaly — WHITE OAKS, ANNUAL OAKS, LEPIDOBALANUS. B. Acorns mature in two seasons; leaves or their lobes bristle-pointed; shell or nut usually pubescent inside; bark dark usually furrowed — BLACK OAKS, BIENNIAL OAKS, ERYTHROBALANUS. The subjoined list shows the respective groups to which the sev- eral Oaks of Pennsylvania belong. White Oak group: 1. White Oak, Quercus alba, 2. Swamp Oak, Quercus bicolor. 3. Post Oak, Querous stellata. 4. Chestnut Oak, Quercus Prinus. 5. Yellow Oak, Querous Muhlenbergii. 6. Bur Oak, Quercus macrocarpa. 7. Chinquapin Oak, Quercus prinoides. Black Oak group: 8. Black Oak Quercus velutina. 9. Red Oak, Quercus rubra. 10. Scarlet Oak, Quercus cocciuea. 11. Pin Oak Quercus palustris. 12. Spanish Oak, Quercus falcata. 13. Scrub Oak Quercus ilicifolia. 14. Black Jack Oak, Quercus marilandica. 15. Laurel Oak Quercus imbricaria. 16. Willow Oak, Quercus phellos. Of the 300 species of Oaks which are known, about 55 species are native to North America, and 16 species to the State of Pennsylva- nia. Of the 16 species native to Pennsylvania, 7 belong to the White Oak group and 9 to the Black Oak group. The centre of distribu- tion of this genus is in the mountains of Central America and Mexico. A few species are found in Europe. The subjoined keys will identify the species native to Pennsylvania. 130 KEY TO THE SPECIES BASED PRIMARILY ON FRUIT AND BUDS. Page. 1. Acorns maturing at end of second season on last season's growth; immature acorns may be present in winter; shell of nut hairy inside; scales on acorn-cup usually broad and thiu 2 1, Acorns maturing at end of first season on growth of season; immature acorns never present in winter; shell of nut not hairy inside; scales of acorn-cup more or less knobby, 10 2. Buds large; terminal ones usually over one-fifth of an inch long, 3 2. Buds smaller; terminal ones one-fifth of an inch or less in length, 7 3. Buds coated with rusty brown hairs prominently angled, 4 3. Buds not coated with rusty brown hairs ; not prominently angled 5 4. Inner bark yellow; buds i-i of an inch long; acorn-cup top-shaped to hemispheric, Q. velutina 142 4. Inner bark not yellow; buds i of an inch long or less; acorn-cup hemispheric Q,. marilandica 145 5. Budr, sharp-pointed, 6 5. Buds blunt-pointed, the widest part, at or just below middle; evidently woolly above middle Q. coccinea, 141 6. Acorn-cups saucer-shaped; buds glabrous except sometimes slightly hairy near apex; bark fissured with intervening broad smooth ridges; branches straight Q. rubra 139 6. Acorn-cups hemispheric; buds light brown and hairy; bark shallowly fissured, with scaly ridges, brarching zigzag, » Q. falcata 143 7. Twigs during first winter dull, finally hairy; shrubs, Q. ilicifolia 144 7. Twigs smooth and shining during first winter; trees, 8 8. Pin-like projections OP lateral branches numerous, standing almost at right angles to branch; trunk continuous; acorn-cup saucer-shaped Q. palustris 140 8. Pin-like projections not present; trunk divided 9 9. Acorn-cups saucer- shaped; buds dark brown; twigs stouter, Q. phellos 147 9. Acorn-cups hemispheric; buds light brown and angular; twigs slender, ..Q. imbricaria 146 10. Buds narrow, conical, sharp-pointed, 1 of an inch or more in length, .....11 10. Buds obtuse, short, usually about i of an inch long, 13 11. Buds pubescent, usually sharp-pointed, lateral buds generally appressed; bark on older twigs with corky ridges; acorn-cups fringed, Q. macrocarpa 134 11. Buds smooth, lateral buds divergent; twigs without corky ridges; acorn-cups not fringed 12 12. Acorns sessile; twigs slender and hairy to smooth, Q. Muhelnbergii 136 12. Acorns evidently stalked; twigs stouter and smooth, Q. Prinus 137 13. Bark on branchlets peeling into long, dark, layer-like scales; acorns long stalked, Q. Tricolor 135 13. Bark on branchlats not peeling off into long, dark, layer-like scales, 14 14. Twigs usually coated with yellowish-brown wool; buds about as long as broad, t a. stellata 133 14. Twigs smooth 15 15. Twigs slender; shrub or small tree; buds about as long as broad; acorn-cup encloses 3 of nut, Q. prinoides 138 15. Twigs stout; large tree; buds longer than broad; acorn-cup encloses J of nut,..Q. alba 132 131 KEY TO THE SPECIES BASED PRIMARILY ON LEAVES AND FRUIT. Page. 1. Leaf -blades or their lobes bristle-tipped; acorns maturing at end of the second season; nuts often pubescent within, 2 1. Leaf-blades or their lobes or teeth without bristle tips; acorns maturing at end of the first season; nuts often glabrous within, 10 2. Leaf-blades entire; rarely lobed or toothed except on vigorous coppice shoots, 3 2. Leaf-blades pinnatifid, pinnately-lobed or dilated at apex 4 S. Lower surface of leaf -blades glabrous, ft,1 phellos 147 3. Lower surface of leaf-blades pubescent, ft. imbricaria 146 4. Leaf- blades pinnatifid or pinnately-lobed, 5 4. Leaf-blades dilated at apex; obovate brown tomentose on lower surface, ft. marilandica 145 5. Leaf -blades green on both upper and lower surfaces, 5. Leaf-blades pubescent on lower surface, 6. Lobes of leaf-blades about equal the width of the middle portion or body of the leaf ft. rubra 139 6. Lcbes of leaf-blades 2-6 times as long as the breadth of the narrowest portion or body of the leaf 7 7. Trunk continuous, covered by short, slender, often horizontal lateral branches; acorn- cups saucer-shaped, Q. palustris 140 7. Trunk usually branched; covered by rather long, usually stout and ascending lateral branches; acorn-cups top-shaped Q. coccinea. 141 8. Leaf -blades brown or rusty pubescent on lower surface; inner bark yellow, ft. velutina. 142 8. Leaf -blades gray or white pubescent on lower surface; inner bark not yellow 9 9. Lobes of leaf -blades long and lanceolate, often scythe-shaped; large tree, ....Q. falcata 143 £>. Lcbes of leaf-blades short and triangular, usually five in number; small tree or shrub ft. ilicifolia 144 10. Leaf-blades deeply lobed 11 10. Leaf -blades coarsely toothed 13 11. Mature leaf -blades glabrous and pale on lower surface; cups shallow ft. alba 132 11. Mature leaf -blades pubescent on lower .surface; cup encloses at least one-third of nut '. 12 12. Mature leaf -blades rusty-pubescent below; leaves usually 5-lobed; stellate pubescent above with three terminal large rounded or squarish lobes; upper scales of acorn- cup not awned, Q. stellata 133 12. Mature leaf -blades white tomentose beneath; leaves usually 5-7-lobed with single large oval and crcnate terminal lobe; upper scales of acorn-cup awned with a heavy fringe ft. macrocarpa 134 13. Leaf-blades broadest at or below the middle, oblong to lanceolate, decidedly pointed at apex, usually exceeding six inches in length, 14 13. Leaf-blades broadest above the middle, oblong to oblong obovate, pointed to rounded at apex, seldom exceeding six inches in length 15 14. Leaf-blades with acuminate apex; slender petiole; acorn sessile, ft. Muhlenbergii 136 14. Leaf -blades with acute apex; stouter petiole; acorn stalked, Q. Prinus. 137 15. Tall tree; bark on small branches often peeling off in dark scales; acorns long- stalked, ft. bicolor 135 15. Shrub or small tree; bark on small branches smooth; acorn sessile, ft. prinoides 138 132 WHITE OAK. Quercus alba, Linnaeus. FORM — A very large and valuable tree, usually attaining height of 70-80 ft. but may reach a maximum height of 140 ft. with a diameter of 8 ft. when grown In a closed stand. When grown in a dense stand (Fig. 11) it has a clean continuous trunk often free from lateral branches for 75 ft. with a diameter of 5 ft., and little stem taper. When grown in the open (Fig. 21) it divides near the ground into a great many lateral branches which are gnarled and twisted forming a deep, wide, and irregular crown or occasionally a symmetrical crown. Open grown trees produce a very small quantity of timber of commercial importance. BARE — On smaller branches light green to reddish-green; on mature trunks up to 2 inches thick, usually light gray or white, shallowly fissured into flat, irregular scales often very loosely attached. Occasionally the bark of trunk appears roughly ridged and without scales. See Fig. 73. TWIGS — During first summer light green, tinged with red, coated with loose, pale hairs. First winter slender, smooth, reddish to gray, covered with numerous, light, minute, elevated lenticels. Pith star-shaped. BUDS — Alternate; terminal buds clustered; broadly ovate, obtuse, reddish-brown, J of an inch long. LEAVES— Alternate, simple, 5-9 inches long, 2-4 inches wide, obovate in outline, with 3-9, but usually 7 ascending lobes; lobes blunt at apex and separated by deep round-based sinuses. When full grown thin, bright green and smooth above, and pale, smooth, and occasionally glaucous below. LEAF-SCARS — Alternate, raised, concave to round above, rounded below. A decurrent ridge often continues from raised leaf-scar which makes the twig 5-angled on account of 5-ranked arrangement of leaf-scars. Bundle-scars are numerous, scattered, inconspicuous. The leaf- scars of the Oaks of this State so closely resemble each other that a description of a leaf- scar of one species will suffice for all. FLOWERS — Flowers appear in May when the leaves are about J developed. Staminate flowers are borne in hairy aments 25-3 inches long. Calyx is very hairy and yellow. Stamens extend beyond calyx. Anthers are yellow and notched. Pistillate flowers are borne on short stalks, with hairy involucral scales and red spreading styles. FRUIT — An acorn, maturing during one season, sessile or short-stalked. Nut ovoid, rounded at apex, shiny, light brown, 3 of an inch long, inclosed for 1 length in cup. Meat of nut is sweet and edible. Cup bowl-shaped, slightly tomentose on inside, covered with numerous scales whi^h are thin, short, flat, blunt-pointed near rim, thickened and knobby near the base. WOOD — Ring-porous; with very conspicuous medullary rays; strong, heavy, hard, close-grained, durable in contact with soil, light brown with lighter sapwood. The most valuable of all oak wood. Weighs 46.35 Ihs per cubic foot. Used in construction, ship building, tight cooperage, furniture, railroad ties, manufacture of wagons, agricultural implements, interior finish of houses, fences and fuel. DISTINGUISHING CHARACTERISTICS — In summer one can distinguish the White Oak very readily by its loose scaly, grayish or white bark from which it takes its common name, and by its deeply round-lobed leaves with a smooth and pale lower surface when mature. In winter it has some characteristics apparently in common with some other Oaks but can be distinguished from the Red, .Black, Scarlet, Chestnut, and Yellow Oaks by its obtuse, rather small buds; from ths Swamp White Oak by the slender reddish to grayish twigs and the absence of dark loose peeling flakes on the branches; from the Post Oak by the absence of greenish rusty pubescence cr the twigs; from the Pin Oak by the absence of stiff lateral pins on the branches and the more obtuse buds; from the Bur Oak by the absence of corky wings on the branches. In addition to these characteristics the acorns and leaves which often persist will aid considerably in recognizing the different species. A careful study of the key to the species will help in bringing out additional distinguishing characteristics. RANGE— Maine to Minnesota, south to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA — Abundant throughout the eastern, central, and south- ern parts, and rather common at least locally, in the northern and western parts. HABITAT — It is tolerant of many soils, growing on sandy plains, gravelly ridges, rich uplands, and moist bottomlands. It reaches its best development in rich moist soil. IMPORTANCE OF THE SPECIES— The White Oak is the most important hardwood species of Pennsyvania. It is a slow grower but develops an exceptionally high grade material. Artificial re- generation by planting is difficult. Sprouting cannot be depended upon. Natural seed regenera- tion is the best method fcy which this species can be successfully reproduced. German experimenta- tion has shown conclusively that the natural method is superior to the artificial, especially with Oak. The great value of its timber will justify attempts to grow this species In forest stands of considerable extent. PLATE LV. WHITE OAK. 1. Flowering branch with immature leaves (s) staminate blossoms, (p) pistillate blossoms, x I. 2. A staminate flower, enlarged. 3. A pistillate flower, enlarged. 4. Branch with mature leaves and mature acorns, x J. 5. Acorn cup, x 5. 6. Acorn, basal view, x J. 7. Longitudinal section of acorn showing em- bryo, x 5. 8. Germinating acorn with its young root and shoot, x |. 9. Winter branch, x j. 10. Terminal section of winter branch showing bud with overlapping scales, a leaf -scar with bundle-scars, and lenticels, enlarged. 11. Cross section of twig showing pentangular pith, wood with conspicuous medullary rays, inner and outer bark, enlarged. PLATE LVI. POST OAK. 1. Branch with mature leaves and mature acorns, x I. 2. Flowering branch with immature leaves, (s) staminate blossoms, (p) pistillate blossoms, x J. 3. An acorn cup, x J. 4. An acorn, basal view, x 5. 5. Lower surface view of mature leaf showing the dense star-shaped pubescence, x t. 6. Winter branch covered with a dense rusty pubescence, x J. 7. Section of winter branch showing slightly pubescent buds, leaf-scars with bundle-scars, lenticels. and the dense rusty pubescent bark, natural size. 133 POST OAK. Quercus stellata, Wangenheim. FORM — A medium-sized tree, usually attaining height of 50-60 ft. but may reach a maximum height of 90 ft. with a diameter of 4 feet. In the open it forms a dense, broad, deep, round- topped crown with stout and spreading branches. Toward its northern limit it is a large shrub. BARK — On trunks somewhat similar to that of White Oak only darker and often rougher and less scaly. On young branches it is often covered with loose, dark scales. TWIGS — Stout, covered with yellowish rusty pubescence, at first light orange In color, later dark brown. Season's growth stands in strong contrast with later growth on account of much lighter color. Pubescence soon turns dark and finally disappears. BUDS — Alternate, broadly ovate, about | of an inch long, sometimes as broad as long, blunt-pointed, covered with numerous overlapping, reddish-brown, slightly pubescent scales. LEAVES — Alternate, simple, obovate in outline, 4-7 inches long, 3-5 inches wide, thick, leathery, generally 5-lobed; the middle pair of lobes is the largest and Is separated by deep sinuses; upper surface of leaf is bright green, shiny; lower surface is paler and coated with rusty pubescence. LEAF-SCA'RS — See "Leaf-Scars" under White Oak, page 132. FLOWERS — Appear about May. Staminate borne in slender ainents 4-6 inches long. Pistillate sessile or short-stalked, woolly; stigmas bright red. FRUIT — An acorn, maturing at end of first season; usually sessile, occurs solitary, in pairs or clustered. Nut oval, 1-1 of an inch long, hairy at apex, longitudinally striped with darker brown, inclosed by cup for J-* of its length. Cup thin, hairy within, and covered with thin, pale, flat woolly scales. WOOD — Ring-porous; with conspicuous medullary rays; heavy, hard, close-grained, very durable, light to dark brown, with light sapwood. Weighs 52.14 Ibs. per cubic foot. Used for the same purposes as White Oak. It is found on the market mixed with White Oak. DISTINGUISHING CHARACTERISTICS — In summer the Post Oak, also known as Iron Oak, may at once be recognized by the peculiar form of its leaves, with large rounded or squarish lobes. The three terminal lobes are the largest and the basal lobes taken together are wedge-shaped in outline. The rigid leathery leaves with their shiny green upper surface and rusty pubescent lower surface, and the rusty pubescent twigs are characteristic. In winter its short obtuse buds and stout rusty pubescent twigs are distinctive. The buds have also a brighter reddish color than those of the White Oak. RANGE — Massachusetts, central Pennsylvania, Kansas, south to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA— Found locally in the eastern and southern parts, but not in the western and northern. HABITAT — Common on dry rocky soil. Found on gravelly uplands, limestone hills, and sandy plains. IMPORTANCE OF THE SPECIES — The Post Oak closely resembles the White Oak, especially in the wood, Avhich is sold as White Oak. On account of its limited distribution in Pennsyl- vania, and the superiority of the White Oak, this species cannot be recommended for forestry purposes on an extensive scale. It will, however, grow on poorer soil than the White Oak and might be established upon such areas. It is difficult to transplant and grows slowly. 134 BUR OAK. Quercus macrocarpa, Michaux. FORM — Usually attains height of about 70-80 feet but may reach a maximum height of 170 feet with a diameter of 6-7 feet. It attains its greatest height in Illinois and Indiana. It has broad spreading branches which form a broad round-topped crown. In the forest the crown is usually contracted and covers only the upper part of the trunk. It is a giant among its associ- ates. BARE — Intermediate between flaky bark of White Oak and very roughly ridged bark of Chestnut Oak. TWIGS— Stout, covered with pale, raised and inconspicuous lenticels, yellowish -brown, at first hairy, later smooth, with corky wings often 15 inches wide. BUDS — Alternate, broadly-ovate, about J of an inch long, acute or obtuse, reddish-brown, slightly pubescent. Lateral buds are closely appressed. LEAVES — Alternate, simple, 6-12 inches long, 3-6 inches wide, obovate or oblong; 5-7 lobed; sinuses round-based; terminal lobe largest; smooth, shiny, and dark green above; paler and finely hairy beneath. LEAF-SCARS— See "Leaf-Scars" under White Oak, page 132. FLOWERS — Mature about May. Staminate flowers borne in slender ament 4-6 inches long. Pistillate sessile or short-stalked, with bright red stigmas and hairy scales. FRUIT — An acorn, maturing during first season; sessile or stalked, usually solitary. Nut ovate, 4/5 — 2 inches long, covered with down. Cup deep, embracing from i to entire nut, light brown, downy on inner side, covered with large imbricated scales forming a distinct fringe near the margin. WOOD — Ring-porous; with conspicuous medullary rays; heavy, hard, strong, close-grained, very durable, brownish with light thin sapwood. Weighs 46.45 Ibs. per cubic foot. Used for the same purposes as White Oak from which it is not distinguished on the market. DISTINGUISHING CHARACTERISTICS — In summer the Bur Oak, also known as Over-cup or Mossy-cup Oak, can be distinguished by its unique leaves, which have deep, rounded sinuses that reach almost to the midrib and divide each side of a leaf almost into two parts. The lobes on the front part are rather squarish and those on the basal part triangular. The pubescence on the lower side of the leaves and the corky winged projections on the branches are also characteristic. In winter the corky winged projections on the branches, the closely appressed and pubescent buds, the distinctly fringed acorn cups, and the persistent leaves are characteristic. RANGE — Nova Scotia to Manitoba, south to Pennsylvania, Kansas and Texas. DISTRIBUTION IN PENNSYLVANIA — Rare or local in the eastern, southern, and western parts of the State. Not reported from other parts. HABITAT — Prefers low rich bottomlands but can grow upon a variety of soils. It does not thrive on uplands so well as the White Oak, grows much slower than the Red Oak, and is rather intolerant of shade. IMPORTANCE OF THE SPECIES — It is one of the very largest of American Oaks, has a wide distribution, and occurs in pure and in mixed stands. This species produces valuable wood especially adapted to quarter-sawing on account of conspicuous medullary rays. It should be re- generated especially in the Mississippi basin where it develops at its optimum. This tree is also very attractive as an ornamental or shade tree, since it withstands smoke more than most other Oaks, and is relatively free from disease. PLATE LVII. BUR OAK. 1. Flowering branch with immature leaves, (s) staminate blossoms, (p) pistillate blossoms, x 4 6. Branch with mature leaves and mature acorns x J 3. An acorn cup, x J. 4. An acorn, x j. 5. A winter branch showing buds, leaf -scars, and raised corky ridges, i i. b. I erminal section of winter branch showing bud with overlapping scales and leaf scar with uu i M 1 1 < ' - s ( * *i r s , oistillate l»— • * d. An acorn, x j. 4. An acorn cup, x j. 5. Terminal section of winter twig x J tion of winter twig showing buds, lenticels, and leaf-scars with bundle-scars, enlarged. PLATE LX. CHESTNUT OAK. 1. Flowering branch with immature leaves, (s) staminate blossoms, (p) pistillate blossoms, x 5. 2. Hranch with mature leaves and mature acorns, x J. 3. An acorn cup, x J. 4. An acorn, x j. 5. A winter twig showing buds, lenticels, leaf-scars, fluted bark, and pentangular pith, x J. 6. Section of a winter twig, enlarged. 7. Cross section of a twig showing pentangular pith, wood with conspicuous medullary rays, inner and outer bark, enlarged. 8. A basal bud-scale with hairy margin, enlarged. 9. An apical bud-scale with hairy margin, enlarged. 137 CHESTNUT OAK. Quercus Prinus, Linnaeus. FORM — A medium-sized tree usually attaining a height of 60-70 ft., occasionally 100 ft., with a diameter 6-7 feet. In dense stands the trunk is straight and continuous while in open stands it is low and divided, forming a very broad open crown. BARK — On young stems and smaller branches smooth, thin, yellowish-brown. On older branches and trunk rough, thick, brown to black, rich in tannin, divided into long, broad and continuous fissures. Ridges are very solid, sharp-angled, not scaly. Base of the fissures often cinnamon -led, especially on the larger branches and smaller trunks. See Fig. 75. TWIGS — First summer greenish-purple; first winter orange or reddish-brown; stout, smooth; bitter; with inconspicuous lenticels and star-shaped pith. BUDS — Alternate, ovate-ccnical, distinctly sharp-pointed, i-l of an inch long. Bud-scales light chestnut-brown, imbricated, slightly hairy towards apex and along margin. LEAVES — Alternate, simple, obovate, thick, stiff, 5-9 inches long, 2-4 inches wide, usually wedge-shaped at base, coarsely dentate with rounded teeth on margin; green and smooth on upper leaf-surface, pale green and at first hairy on lower. LEAF-SCARS — See "Leaf Scars" under White Oak, page 132. FLOWERS — Appear about May when leaves are about i developed. Staminate flowers are yellow and borne in hairy aments 2-3 inches long. Pistillate flowers have a short divergent, red- dish style, and occur in small groups upon stout stalks. FRUIT — Solitary or in pairs; matures in one season on short stalks. Nut 4/5-1* inches long, 2-3 times as long as broad, smooth, glossy, oval, chestnut-brown, acute or round-pointed, and contains a sweet kernel. Cup thin, deep, hemispheric, covers J of nut, hairy inside. Scales of cup are thin-tipped, reddish-brown, rather knobby near the base. WOOD — Ring-porous; with prominent medullary rays; heavy, strong, close-grained, durable in contact with soil, dark brown with lighter sapwood. Weighs 46.73 Ibs. per cubic foot. Used for railroad ties, fencing, fuel and construction. Ranks close to White Oak. DISTINGUISHING CHARACTERISTICS — In summer the Chestnut Oak, also known as Rock Oak, can be distinguished by its oblong leaves margined with course rounded teeth and the roughly fis&ured and non-scaly bark. In winter one can readily recognize it by its characteristic bark, its sharp-pointed conical buds and its distinctive fruit. The persistent leaves often aid in recognizing it in winter, as well as the absence of 1-year old developing acorns. The slender, angular, orange-brown twigs terminated by a cluster of light brown sharp-pointed buds with a slight apical pubescence will always determine this species with certainty. • RANGE — Maine to Ontario, south to Alabama and Tennessee. DISTRIBUTION IN PENNSYLVANIA — Common In the mountainous region of the State. Locally it becomes a prevailing tree. HABITAT— Usually found on dry hillsides and towards the south in the mountains. It reaches its best development in the mountains of western North Carolina, eastern Tennessee and Ken- tucky upon rich rnoist soil. It is light-demanding and unless crowded will develop often into a crooked tree. IMPORTANCE OF THE SPECIES— The Chestnut Oak belongs to the White Oak group. Its wood is used practically for the same purposes as that of the White Oak. The wood is valuable and in addition the bark is very valuable because it is richer in tannin than that of any other Oak. Large quantities of this bark are harvested annually at the present time in the southern Appalachians. This species deserves to be regenerated extensively, especially by natural seed regeneration methods and admixed with the well known Chestnut. In case of artificial regenera- tion it may be advisable to sow the seeds rather than plant seedlings since this species is rather sensitive to transplanting. 138 SCRUB CHESTNUT OAK. Quercus prinoides, Willdenow. FORM — Usually a low shrub from 2-5 ft. high, but may attain a height of 18 ft. with a diameter of 4 inches. Usually occurs in clumps but may occur solitary. BARK— Thin, bitter, light brown, marked with light gray blotches, at first smooth, but later when trunk reaches a diameter of 4 inches it becomes rough. TWIGS — Smooth, slender, at first dark green and rusty -pubescent but later reddish-brown and smooth, marked with rather inconspicuous pale lenticels. BUDS — Alternate, ovate, rounded at apex, light brown, covered with thin overlapping scales which are sometimes hairy on margin. LEAVES — Alternate, simple, obovate, 3-6 inches long, 2-3 inches wide, covered beneath with pale tomentum, short and stout-petioled, margined with 3-7 rounded teeth on each margin and terminated with acute or acuminate apex. LEAF-SCARS — See "Leaf -Scars" under White Oak, page 132. FLOWERS — Appear about May when leaves are about $ developed. Staminate aments 1J-24 inches long, yellow and somewhat hairy. Pistillate flowers short-stalked and bear bright red pistils. FRUIT — An acorn, maturing at end of first season; 3-5 of an inch long, sessile or short- stalked, often produced in great abundance, singly or in pairs. Nut oval, light chestnut-brown; when young striated with dark longitudinal lines; blunt-pointed, shiny except at apex where it is often covered with pale down. Kernel sweet and edible. Cup thin, rather deep, covers about i of nut, pale woolly outside, downy inside. Scales are indistinct, thinner towards apex, often knobby or tumid towards base. WOOD — Ring-porous; with consipcuous medullary rays. Commercially not important on account of small size. Locally used for fuel. DISTINGUISHING CHARACTERISTICS— The Scrub Chestnut Oak, also known as Dwarf Chin- quapin Oak, Chinquapin Oak and Scrub Oak, can readily be distinguished from most of the Oaks of Pennsylvania by its dwarf forms. It resembles the Bear Scrub Oak rather closely but can be distinguished from it by its round-lobed leaves, knobby acorn-scales, scaly and often gray- blotched bark on larger stems, and sweet kernel of the acorns. The young branches of this species are pubescent while those of the Scrub Oak are usually smooth. The buds are small and not so sharp-pointed as those of the Chestnut Oak and the Yellow Oak, RANGE — Maine to North Carolina, west to Kansas and Texas. DISTRIBUTION IN PENNSYLVANIA— Found locally In the eastern, southern and central parts of the State, nowhere very common. HABITAT — Prefers dry woods, rocky slopes or sandy soils. Occasionally found in hillside pastures and moist woods. IMPORTANCE OF THE SPECIES— The Scrub Chestnut Oak is so small in size that it has practically no commercial value. It is hardly more than a forest weed and should not be planted or protected except where it might be used as an advance growth. PLATE LXI. SCRUB CHESTNUT OAK. 1. Flowering branch with immature leaves, x 5. 2. A staminate flower, enlarged. 3. A pistillate flower, enlarged. 4. A fruiting branch, x J. 5. An acorn cup, x J. 6. An acorn, x J. 7. A winter twig, x $. 8. Section of a winter twig, enlarged. PLATE LXII. RED OAK. 1. Flowering branch with immature leaves, (s) staminate blossoms, (p) pistillate blossoms, (i) immature acorns, x J. 2. A staminate flower, enlarged. 3. A pistillate flower, enlarged. 4. Branch with mature leaves, (i) immature acorns, 'm) mature acorns, x i. 6. Winter twig with immature acorns, buds, and leaf-scars, x i. 6. An immature acorn, enlarged. 7. An acorn CUD, x i. 8. An acorn, £ 1. 9. Section of a twig, enlarged. 10. A bud-scale, enlarged. . , : . . 139 RED OAK. Quercus rubra, Linnaeus. FORM — One of the largest forest trees of the Northern States, usually attaining a height of 70-90 ft. with a diameter of 2-4 ft. but occasionally reaching a height of 150 ft. with a diameter of 5 feet. When grown in the open has a short trunk and a broad symmetrical crown; in dense forest stands the trunk is straight, clean and continuous bearing a small, narrow crown. The straight ascending and clean branches of the crown are characteristic. BARK — On young stems and branches smooth, gray to brown; on older trunks it is thick, slowly broken up by shallow fissures into regular, continuous, dark-brown and distinctly flat- topped ridges. Trunks above 8 ft. in diameter are often very rough near the base, having lost the characteristic flat-topped ridges which are, however, retained higher up on the stem. See Fig. 72. TWIGS — Rather slender, smooth, greenish-brown to dark brown, covered with pale indistinct lenticels; pith star-shaped. BUDS — Alternate, ovoid, 1/6-1/3 of an inch long, widest part near middle, narrowed up- ward to a sharp point, light brown, and free from woolly covering. Bud-scales numerous, overlapping, light brown, slightly longitudinally-striate, with slightly pubescent margins. LEAVES — Alternate, simple oval to obovate in outline, 5-9 inches long, 4-6 inches wide, 7-9-lobed, with sinuses extending half-way to the midrib and separating ascending lobes with entire margin or few bristle-pointed teeth. Mature leaves firm, dull green, with yellowish to reddish midrib above and pale with a yellowish midrib below. LEAF-SCARS — See "Leaf-Scars" under White Oak, page 132. FLOWERS — Appear about May when leaves are about I developed. Staminate borne in slender, hairy aments 4-5 inches long, with greenish 4-5-lobed calyx and 4-5 stamens terminated by yellow anthers. Pistillate borne on short stalks; involucral scales broadly ovate, blunt, pubescent; calyx lobes sharp-pointed; style spreading recurved, light green. FRUIT — An acorn, maturing at the end of second season, solitary or paired, short-stalked. Nut ovoid, §-lJ inches long, flat at base, narrowed at apex. Cup velvety inside, broad, shallow, covering only base of nut, with closely imbricated, sometimes hairy, reddish-brown scales. Immature acorns usually divergent from twig, with basal scales reaching about I of the way up, and appearing as if arranged in 3 rows. WOOD — Ring-porous; with conspicuous medullary rays; heavy, strong, hard, close-grained, light reddish-brown, with thin lighter colored sapwood. Used for furniture, cooperage, con- struction, interior finish of houses, and railroad ties. Weighs 41.25 Ibs. per cubic foot. The wood of this species as well as that of the Black Oak and Scarlet Oak. is relatively poor but is coming more into use daily. The despised species of to-day may be prized to-morrow. DISTINGUISHING CHARACTERISTICS— The Red Oak may be recognized by its flat-topped ridges of the bark, its straight clean branches, its large dull green leaves with red midribs and ascending lobes with entire or few bristle-teeth, its light reddish inner bark, its glabrous, sharp-pointed, light brown buds which are often constricted at the base, and its large acorns with broad and shallow cups. RANGE — Nova Scotia to Minnesota and Kansas, south to Florida and Texas. Planted extensively in Europe for ornamental and forestry purposes. DISTRIBUTION IN PENNSYLVANIA— Found throughout the State. At its optimum in the Cumberland Valley and adjoining lower slopes. Rarer in the northern than in other parts. HABITAT — Prefers porous sandy or gravelly clay soil. It will not grow in wet soils and is also intolerant of shade, except when young. IMPORTANCE OF THE SPECIES— The Red Oak is the most rapid growing species of all the Oaks. In one year it has grown to the height of 19 inches, in 10 years 18 feet, 20 years 33-39 feet, 50 years 50-57 feet. It deserves to be planted and regenerated naturally on an extensive scale. In a single small nursery the Pennsylvania Department of Forestry in 1911 raised over 200,000 seedlings of this species. In Germany it has at present a wider distri- bution than any other American hardwood species. It is very attractive ornamentally on account of its smooth bark, straight branches, and the form and autumnal coloration of its leaves. 140 PIN OAK. Quercus palustris, Muench. FORM — A medium-sized tree usually attaining a height of 50-60 ft. with a diameter of 2 ft., but may reach a maximum height of 120 ft. with a diameter of 3 feet. Trunk straight, usually clean, continuous, and bears a symmetrical conic crown. The lower lateral branches are short and drooping, the middle horizontal, and the upper ascending. The form of the tree is characteristic. See Figs 38 and 89. BARK — On old trunks relatively smooth but slightly roughened by shallow fissures separating low ridges which are covered by small close scales. On young trunks shining, very smooth, light brown to reddish. See Fig. 76. TWIGS — Slender, tough, lustrous, at first hairy, later smooth, dark red to grayish-brown, covered with pale and inconspicuous lenticels. BUDS— Alternate, smooth, J of an inch long, small, ovoid, sharp-pointed, covered with light brown scales which may sometimes be slightly hairy on the margin. LEAVES — Alternate, simple, 4-6 inches long, 2-4 inches wide, ovate in outline, 6-9-lobed; lobes bristle-pointed, separated by broad deep and round-based sinuses. When full grown dark shining green above, pale green and smooth below, often with small tufts of hairs in the leaf axis. LEAF-SCARS— See "Leaf -Scars" under White Oak, page 132. FLOWERS — Appear about May when leaves are about J developed. Staminate flowers in slender and hairy aments from 2-3 inches long. Pistillate short-stalked and terminated by spreading bright red styles. FRUIT — An acorn, maturing at the end of the second season, solitary or in pairs. Nut globose, light brown, often striped, about J of an inch long. Cup thin, saucer-shaped, shallow, i of an inch across, encloses only about 2/5 of nut, covered with thin closely overlapping scales. Kernel bitter and pale yellow. WOOD — Ring-porous; with conspicuous medullary rays; heavy, strong, hard, close-grained, checks and warps badly during seasoning. Weighs 43.24 Ibs. per cubic foot. Used for cheap construction, cheap cooperage, railroad ties, and occasionally for interior finish. DISTINGUISHING CHARACTERISTICS— The Pin Oak, also known as the Swamp Oak and Water Oak, when young and especially when open grown, can readily be recognized by its characteristic form. Its trunk is continuous, relatively smooth, and covered by many slender and rather short lateral branches which are drooping below, erect above, and horizontal in the middle. It frequents moist locations and bears small acorns with shallow cups. The branchlets are often beset with short, stiff lateral shoots which give it its common name. The buds are small, smooth, sharp-pointed, and light brown in color. RANGE — From Massachusetts to Michigan and Missouri, south to Virginia, Tennessee, and Oklahoma. DISTRIBUTION IN PENNSYLVANIA— Common in the eastern and southern parts. Occa- sional in the mountainous parts. Sparse in the western part. HABITAT — It occurs in rich moist soil of river bottomlands, along streams, on border of swamps, and even thrives in fertile soil on the slopes and summits of the Allegheny mountains. IMPORTANCE OF THE SPECIES— This species does not rank high from a commercial point of view even among the Black Oak group of which it is a member. It is singularly beaHitiful for ornamental purposes. It deserves to be planted extensively as a shade, park, or avenue tree on account of its rapid growth, its beautiful form, and autumnal foliage, and the ease with which it is transplanted. Its commercial value, however, does not recommend it for extensive planting for forestry purposes. PLATE LXIII. PIN OAK. 1. Flowering branch with immature leaves, (s) staminate blossoms, (p) pistillate blossoms, (i) immature acorns, x 5. 2. liranch with mature leaves, immature and mature acorns, x i. 3. An acorn cup, x 5. 4. An acorn, x \. 5. Winter twig with immature acorns, buds, and one pin-like branchlet, x J. 6. Winter branch with two pin-like branchlets, x J. 7. Section of a winter branch, enlarged. PLATE LXIV. SCARLET OAK. 1. Flowering branch with immature leaves, (s) staminate blossoms, (p) pistillate blossoms^ (i) immature acorns, x J. 2. Branch with mature leaves, immature and mature acorns, x J. 3. An acorn, x J. 4. An acorn cup. x J. 5. Terminal section of a winter twig, x J. 6. Section of a winter twig showing lenticels, leaf-scars with bundle-scars, and two slightly angular buds covered with numerous over-lapping scales, enlarged. 7. An apical bud-scale with ciliatc margin, enlarged. 8. A basal bud-scale, enlarged. 141 SCARLET OAK. Quercus coccinea, Muench. FORM — An average-sized tree usually attaining a height of 60-80 ft., but occasionally reaching a height of 150 ft. with a diameter of 4 feet. Lateral branches ascending above, horizontal in middle, drooping below. Lateral branches are slender and lowtr ones die readily from shading, only persist for many years. Trunk very tapering, crown shallow and narrow. BARK — On old trunks intermediate between the Red Oak and the Black Oak. It is broken up into rough, irregular, deep fissures which separate ridges not so rough as those of the Black Oak and not so flat-topped as those of the Red Oak. Inner bark red to gray. On younger limbs thin, smooth, light brown. See Fig. 78. TWIGS — Slender, smooth, reddish or grayish-brown, covered with numerous, small, fcmle lenticels; pith star-shaped. BUDS — Alternate, broadly ovate, narrowed to a blunt apex, i-J of an inch long, dark reddish-brown, covered with a pale wool from the middle to the apex. LEAVES — Alternate, simple, broadly oval to obovate, 3-6 inches long, 2J-5 inches wide, 5-9-lobed, lobes bristle-pointed and separated by deep round-based sinuses extending at least § of the distance to the midrib. In autumn brilliantly scarlet before falling. LEAF-SCARS — See "Leaf -Scars" under White Oak, page 132. FLOWERS — Appear about. May when leaves are $ developed. Staminate flowers are borne in slender pubescent aments 3-4 inches long. Pistillate on short pubescent stalks, reddish in color, with reflexed bright red stigmas. FRUIT — An acorn, maturing at the end of the second season, sessile or short-stalked, solitary or paired. Nut ovoid, 2/5-4/5 of an inch long, reddish-brown, occasionally striate. Cup thin, covering about i of the nut, narrowed at base, with closely imbricated, sharp- pointed, slightly downy scales often forming a fringe at the cup margin which is closely appressed to the nut. WOOD — Ring-porous; with prominent medullary rays; strong, heavy, coarse in texture. Weighs 40.15 Ibs. per cubic foot. The wood has little commercial value as timber. DISTINGUISHING CHARACTERISTICS— The Scarlet Oak is one of the commonest of the Black Oak group and can readily be distinguished from the Black Oak by its smoother bark ridges on the trunk, its paler inner bark, its deeper round-based leaf -sinuses, its smooth, close-fitting scales of the acorn-cup, and its stouter, often smaller, less angular buds which are covered with pale wool only from the middle to the apex while the Black Oak is dis- tinctly woolly over the entire bud. It can be distinguished from the Red Oak by its smaller and more deeply lobed leaves, its less flat-topped ridges of the bark, its smaller and deeper- cupped acorns, and its buds which are covered with a pale wool from the middle to the apex while those of the Red Oak are free from wool. The persistent, stunted, often drooping and dead lateral branches are also peculiar to this tree. Thi$ characteristic is common to trees on the border of bodies of water. RANGE — Maine to Minnesota, south to North Carolina and Nebraska. DISTRIBUTION IN PENNSYLVANIA — Common in the eastern, central, and southern parts. Sparse in western part. Rare in northern part. HABITAT — Prefers dry sandy soil. Frequently met upon light stony or sandy uplands but the best individuals occur on good soil at the base of the slopes where it is often found bordering hollows filled with water during spring. IMPORTANCE OF THE SPECIES— The wood of the Scarlet Oak is of little commercial importance as compared with some of the other oaks. The wood is sold on the market as Red Oak but is inferior in quality to the latter. This species is often attacked by fungi when it has reached medium size, which causes the wood to rot and often results in wind-break in the forest. This species on account of its fast growth, beautiful foliage with its special autumnal coloration, is one of the most desirable trees for street or park. 142 BLACK OAK. Quercus velutina, Lambert. FORM — One of the largest Oaks of Pennsylvania usually 60-80 ft. high, but may attain a maximum height of 150 ft. with a diameter of 4J feet. Trunk usually clean and continuous giving off ascending branches above and horizontal ones below. Branches rather stout and zigzag. Crown deep, irregular, narrow to wide-spreading, oblong in outline. EARK — On young stems smooth and dark brown, but soon becoming rough and black. On old trunks very rough, thick, broken into deep fissures separating thick ridges which are cross-fissured. Young trees 2-4 inches in diameter often start to develop rough bark. Inner bark is yellow and bitter,' a good distinguishing characteristic. See Fig. 74. TWIGS — Stout, rusty-pubescent, reddish-brown, angular, longitudinally ridged from leaf- scars; taste bitter; covered by rather conspicuous pale lenticels. BUDS — Alternate, ovate, large, J-* of an inch long, strongly angled, tapering to obtuse apex, covered with numerous overlapping bud-scales with a coating of yellowish to dirty-white pubescence. LEAVES — Alternate, simple, obovate to oblong, 4-6 inches long, 3-4 inches wide, usually 7- lobed terminated by bristle points. Mature leaves are dark green and smooth above and pale to yellowish -green below with tufts of rusty hairs in axil of veins at midrib. The leaves vary from those of the Red Oak. No other Oak produces so many differently shaped leaves on the same tree. LEAF-SCARS — See "Leaf -Scars" under White Oak, page 132. FLOWERS — Appear about May when leaves are i developed. Staminate flowers occur in hairy aments 4-6 inches long. Pistillate are borne on short hairy stalks. FRUIT — An acorn, maturing during two seasons, sessile or stalked, solitary or clustered. Nut ovate to oval, i-1 inch long, light reddish-brown, often coated with pubescence and longitudinally striate. Cup thin, tapering at base, dark reddish-brown, embracing & nut, covered with thin, light brown, sharp-pointed, hairy scales tightly overlapping at base and loosely overlapping at margin so as to form a fringe-like margin to the cup. WOOD — Ring-porous; with conspicuous medullary rays; hard, heavy, strong, not tough, durable, checks readily. Heartwood is light brown, with lighter-colored sapwood. Weighs 43.90 Ihs. per cubic foot. Used for furniture, interior finish, cheap cooperage, and ordinary construction. In general it finds the same uses as Red Oak. DISTINGUISHING CHARACTERISTICS— The Black Oak is also known as Yellow Oak and Quercitron on account of its yellow inner bark. The dark colored and rough outer bark, even on young stems, and the yellow inner bark are at all seasons of the year definite marks of identification. The leaves, which vary from the shallow lobed ones similar to those of the Red Oak to the deep lobed ones similar to those of the Scarlet Oak, may also help to identify the species. No other species of Oak has so many varieties of leaves on the same tree as the Black Oak. In autumn the small acorns with the cup embracing one-half of the nut may also help to distinguish it from some species like the Red Oak and the Pin Oak. The large, angular buds covered over the whole surface with a pale wool are sure characteristics. RANGE — Maine to Western Ontario, south to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA— Common in the eastern, central, and southern parts. Sparse in western part. Rare in the northern part. HABITAT — Usually found on dry uplands, gravelly plains and ridges, especially in the Appalachian foothills. Seldom found in rich bottomlands. In the west usually found on sterile, sandy, or glaciated hills. IMPORTANCE OF THE SPECIES— The Black Oak should be propagated only where no better trees can be grown. If its reproduction is thought desirable it should be attempted by natural seed regeneration or planting of seeds since planting of young seedlings from the nursery is expensive and success doubtful. Formerly the yellow inner bark was in demand because an extract in the form of a yellow dye, known as "Quercitron," was obtained from it. The introduction of aniline dyes has decreased the demand. The Black Oak is not attractive as an ornamental tree. PLATE LXV. BLACK OAK. 2' Armature leaf ^x l^ iminature leaves- orne on hairy and slender stalks. FRUIT — Ripens in September or October and is arranged in small umbels. A subglobose to ellipsoidal pome, yellowish-green, later dark reddish-brown, pubescent, about 2/5 of an inch thick, crowned with calyx lobes; containing usually 3-4 nutlets. WOOD — Similar to that of the Cockspur Thorn, page 170, only heavier and more valuable. Used for canes, napkin rings, engraving blocks, rulers. The wood is of a high quality, taking a fine polish but the tree is small and scarce. DISTINGUISHING CHARACTERISTICS— The Scarlet Hawthorn, also known as White Thorn, Scarlet Fruited Thorn, Thorn, Thorn Apple, and Hawthorn, can be distinguishel by its broadly ovate leaves and reddish-brown globose fruit, both of which are pubescent. The leaves are 5-9-lobed or deeply cut and finely serrate. The small nearly spherical chestnut-brown buds and the slender usually straight thorns on the branches will aid in distinguishing It from most of our native species of trees. It is next to impossible to distinguish all the species of the genus Crataegus from each other. RANGE — Eastern Massachusetts and Vermont, southward through New York and Pennsylvania to Nortn Carolina. DISTRIBUTION IN PENNSYLVANIA— Found throughout the State. Not so abundant In the northern and southwestern parts as elsewhere. HABITAT — Usually found In rocky woods and old pastures with sandy or gravelly soil. Rather common along fences. IMPORTANCE OF THE SPECIES— This species is of no commercial importance in the forest. It is, however, attractive- on account of its flowers, autumnal color of its foliage, and the cplor of its persistent fruit. 172 AMERICAN CRAB APPLE. Pyrus coronaria, Linnaeus. GENUS DESCRIPTION — This genus embraces about 40 species of small trees and shrubs which inhabit the north temperate zone. About 10 species are native to North America and 6 to Pennsylvania. No important timber trees are members of this genus but some of our important fruit trees like the Apples and Pears belong here. Both our Common Pear and Common Apple have been introduced from Europe. Some authors make a distinct genus, Malus, for the Apples and another one, Sorbus, for the Mountain Ashes. Both are included under Pyrur. in this publication. FORM— A small tree which may attain a height of 25 ft. with a diameter of 14 inches. Trunk usually short and bearing rather slender, spreading, and crooked branches which form a rather broad round- topped crown. BARK — Up to J of sn inch thick, reddish-brown, roughened by longitudinal furrows which separate low ridges often covered with scales. TWIGS — Rather stout, at first white-woolly, later smooth, reddish -brown, after first year bearing stubby spurs or sometimes sharp spines. BUDS — Alternate, about |-J of an inch long, bright red, blunt-pointed or on vigorous terminal shoots sharp-pointed and curved, covered with 4-8 visible scales. LEAVES — Alternate, simple, ovate or elliptical, 3-4 inches long, usually rounded at base, sharp-pointed at apex, sharply serrate on margin, usually smooth, dark green above, pale green below. Stipules long, falling early. LEAF-SCARS — Alternate, raised on projection of twigs, crescent-shaped; with usually 3 conspicuous bundle-scars. FLOWERS — Appear in May or June when the leaves are almost fully developed. Perfect, fragrant, rosy-white, about U-2 inches across, arranged in umbel-like cymes. The flowers as a whole resemble those of the Common Apple. FRUIT — Ripens about October. Pome or apple-like, borne on long slender stalks, depressed- globose, 1-1J inches in diameter, crowned with persistent calyx lobes and filaments, yellowish- green, fragrant. The flesh is clear and heavily charged with bitter malic acid. Seeds chestnut- brown and shiny. WOOD — Diffuse-porous; rays not distinct; hard, heavy, light reddish-brown. Weighs about 40 Ibs. per cubic foot. Used for carving, engraving, tool handles, and some turned articles. DISTINGUISHING CHARACTERISTICS — The American Crab Apple closely resembles our cultivated apple only tLc leaves of the former are smoother, the flowers more brilliant red, and the fruit smaller and very bitter. The fruit often persists far into winter and does not tot readily. It can be distinguished from the closely related Narrow-leaved Crab Apple (Pyrus angustifolia, Ait.) by its persistent calyx-lobes on the fruit, and by its ovate leaf -blades while those of the latter are usually lanceolate. RANGE — Ontario south through South Carolina to Alabama, west to Michigan, Missouri, and northern Louisiana. DISTRIBUTION IN PENNSYLVANIA— Common in the southwestern part of the State. Local outposts reported from the central and western ports of the State. Peter Kalm, a pupil of Linnaeus, who travele-1 ia America in 1753, reported this species "plentiful in Pennsylvania." HABITAT — Usually found in thickets and open woods where rich moist soil is present. Probably occurs most frequently on little hill-tops near streams and ponds. IMPORTANCE OF THE SPECIES — This species is of no commercial importance as a forest tree. It rarely exceeds 25 ft. In height. The fruit is used for jellies and for cider. It is a most attractive ornamental tree on account of its fc'howy and fragrant flowers produced in great profusion. PLATE XC. AMERICAN CRAB APPLE. 1. A flowering branch, x i. 2. Longitudinal section of a flower, enlarged. 3. A fruiting branch, x i. 4. Section of a fruit, natural size. 5. A winter twig, natural size. 6. Section of a winter twig, enlarged. PLATE XCI. AMERICAN MOUNTAIN ASH. 1. A flowering branch with leaves, x J. 2. Longitudinal section of a flower, enlarged. 3. A fruiting branch, x J. 4. Section of a fruit, enlarged. 5. A winter twig, natural size. 6. Section of a winter twig, enlarged. 173 AMERICAN MOUNTAIN ASH. Pyrus americana, (Marshall) De Candolle. FORM — A small tree rarely exceeding 20 ft. in height with a diameter of 12 inches. A tree 14 inches in diameter is reported from Lycoming county. Trunk rather short and the crown narrow and round-topped. BARK — Thin, smooth or slightly scaly and grayish. TWIGS — Rather stout, smooth, grayish to reddish-brown, covered with conspicuous, pale, oblong lenticels, pith large, brownish. BUDS — Alternate, puiplish-red, smooth or slightly hairy on outside but densely hairy on inside; terminal buds large, about i of an inch long, broadly conical, with 2-3 visible bud- scales, sharp-pointed and often curved at apex; lateral buds about i of an inch long, closely appressed, somewhat flattened, with 1-2 visible bud-scales. LEAVES — Alternate, compound, 6-10 inches long, with 13-17 sessile leaflets. Leaflets in pairs except terminal one, lanceolate, 2-3 inches long, sharp-pointed at apex, serrate on margin, tapering or rounded at base. Smooth and dark yellowish-green when full grown, turning yellow in autumn. LEAF-SCARS — Alternate, rather large, elevated on a projection of the twig, broadly U-shaped, with wavy margin, containing 3-5 bundle-scars. FLOWERS — Appear about May when the leaves are fully developed. They are white, perfect, about i of an inch across, arranged in flat cymes 8-4 inches across. FRUIT — Arranged in flat-topped clusters, persisting far into winter, berry-like, about the size of a medium-sized cherry, bright red, round or pear-shaped, in winter wrinkled, its flesh strongly acid. WOOD — Diffuse-porous; rays indistinct; soft, weak, brownish, close-grained. Weighs about 34 Ibs. per cubic foot. Not used commercially. DISTINGUISHING CHARACTERISTICS— The American Mountain Ash can be distinguished l»y its alternate compound leaves with 13-17 sessile leaflets which are conspicuously toothed. The flat-topped cymea of white flowers measuring about 3-4 inches across, and the bright red fruit about the size of a pea and arranged in flat-topped clusters are characteristic. The stout grayish to reddibh-brown twig with conspicuous pale lenticels and the purplish-red, sharp pointed, somewhat gummy and usually smooth alternate buds are also characteristic. RANGE — Newfoundland westward to Manitoba and Iowa, southward in the mountains to North Carolina. DISTRIBUTION IN PENNSYLVANIA— Limited to the mountainous region of the State. A line drawn from the western part of Tioga county south to Somerset county and thence north- east to Monroe county will include the general distribution of this species. HABITAT — Prefers moist or rocky hillsides. Often found on the border of streams and locally common on rocky hillsides. IMPORTANCE OF THE SPECIES— This species is of no commercial importance. It rarely exceeds a height of 2C-S.P ft. with a diameter ->f 12-15 inches. It is rather attractive and de- serves to be planted for ornamental purposes. Its attractive ornamental features are its form, broad cyme-like clusters of white flowers, and its bright red clusters of fruit which ripen in autumn. 174 SHAD BUSH. Amelanchier canadensis, (Linnaeus) Mendicus. GENUS DESCRIPTION — The genus Amelanchier comprises about 30 species of small trees and shrubs found mainly in the temperate portion of the northern hemisphere. About 23 species are found in North America, 6 of which attain tree-size. Four species are native to Pennsylvania, only 1 of which attains tree-size. FORM — A small tree usually 10-25 ft. in height with a diameter of 6-12 inches but may reach a height of 40 ft. with a diameter of 20 inches. Trunk usually straight, slender, with little taper, bearing a shallow, and narrow crown appearing very dense on account of abundant fine sprays of branchlets. BARK — Rather smooth on young and old specimens. On older specimens there is a tendency to roughen through shallow, longitudinal, sometimes diagonal fissures which are rather dark and separate broad, lighter, and smooth ridges becoming scaly near the base. TWIGS — Slender, somewhat zigzag, bright green to purplish-brown, smooth or often overlaid with a grayish film-like coating which peels off; covered with a few, pale, scattered lenticels; pith small, greenish, angular. BUDS — Alternate, usually 2-ranked, slender, conical, J-J of an inch long, 3-4 times as long as broad, sharp-pointed, greenish-brown often tinged with purple, sometimes smooth often hairy towards apex and along bud-scales. Terminal buds longer than lateral which are usually appiessed close to twig, sometimes remaining very small. Bud-scales largest near base, often 3-nerved, darker and finely hairy along margin. LEAVES — Alternate, simple, ovate to ovate-oblong, 3-4 inches long, sharp-pointed at apex, round or heart-shaped at base, finely and sharply serrate on margin, at first finely hairy, later smooth, dark green above, paler below. LEAF-SCARS— Alternate, usually 2-ranked, small, inconspicuous, rather linear with projection at bundle-scars which aro large and 3 in number. FLOWERS — Appear about April when leaves are just starting to develop; large, white, per- fect, stalked, arranged in drooping racemes 3-5 inches long. FRUIT — Matures in June or July. Berry-like in racemes, reddish-purple, with a bloom when fully ripe, about J of an inch in diameter, sweet, and containing small seeds. WOOD — Diffuse-porous; rays numerous, indistinct, dark brown often touched with red; heavy, hard, strong, checks sind warps easily, very susceptible to high polish. Weighs 48.85 Ibs. per cubic foot. Used to a limited extent, mainly in turnery. DISTINGUISHING CHARACTERISTICS— The Shad Bush, also known as Service Berry, June Berry, and Sarvice, can readily be distinguished in winter by its smooth grayish often black- streaked bark and its long, slender, conical, sharp-pointed, greenish-brown to purplish buds which are often finely hairy towards the apex and along the margin of the scales. The buds, in form and to some extent in size, resemble the Beech but the buds of the Beech are usually larger, clear reddish-brown in color and have from 10-20 scales arranged in 4 rows. The twigs of the Beech are shining reddish-brown while those of the Shad Bush are usually bright green to grayish or purplish-brown. The stipule scars are absent on the Shad Bush while they nearly encircle the twig of the Beech. The large white flowers arranged in drooping racemes 3-5 inches long are also characteristic. The leaves and the fruit will aid in distinguishing it in summer. RANGE — Newfoundland and Ontario, southward to Florida, westward to Kansas and Louisiana. DISTRIBUTION IN PENNSYLVANIA — Found in every portion of the State. Most abundant among the mountain ranges. HABITAT — Occurs solitary or occasionally in clumps. Prefers open situations and moist soil, but also grows on sandy rather sterile soil. Common along the border of forests, banks of streams, forest roads, and cliffs. Small specimens common in the understory of our hardwood forests. IMPORTANCE OF THE SPECIES — This species is of little commercial importance because its wood is rarely used. It will always be a minor species not on account of the Inferiority of its wood but on accoant of its small size and limited and scattered distribution. The wood is actually stronger and stiffer than White Oak. Its conspicuous white flowers in early spring before the leaves are out justify its retention in the forest, especially where it does not inter- fere with the growth of other more valuable trees. The berries are excellent food for birds, beasts, and man. PLATE XCII. SHAD BUSH. 1. A flowering branch, x J. 2. Longitudinal section of a flower, enlarged. 3. A fruiting branch with mature leaves, x J. 4. Section of a fruit, enlarged. 5. A winter twig, natural size. 6. Section of a winter twig, enlarged. PLATE XCIII. BUTTONWOOD. 1. A flowering branch, x 1. 2. A head of flowers with most of the flowers removed, 3. A staminate flower, enlarged. 4. A pistillate flower, enlarged. 5. A fruiting branch with mature leaves, x 1. 6. An achene, enlarged. 7. A winter twig with two beads of fruit, x J. 8. Section of a twig showing a subpetiolar bud, x }. 9. Section of a twig showing a stipule, natural size. 10. Section of a winter twig, enlarged. 175 BUTTONWOOD. Platanus occidentalis, Linnaeus. FAMILY AND GENUS DESCRIPTION— The Plane Tree family, Platanaceae, comprises only 1 genus, Platanus, with about 7 species, 3 of which are native to the United States and 1 to Pennsylvania. In addition to the 1 species native to this State, the Old World Plane Tree (Platanus orientalis L.) is very commonly planted as a shade tree in the eastern states. FORM— Usually attains a height of 70-125 ft., but may reach a height of 140-170 ft. with a diameter of 10-11 feet. It is the most massive of the deciduous trees of North America. Trunk usually branches near the base into heavy sub-trunks, which sub-divide and form a very deep, wide-spreading, rather open, and irregular crown. BARK — Oil old trunks rather thick, rigid, roughened by shallow fissures separating broad ridges whicli peel off into thin dark brown scales. On young trunks and upper parts of old ones it peels off spontaneously into 'large thin plates exposing a whitish, yellowish, or a greenish inner bark. This mottled inner bark is characteristic, but rarely found near the ground. See Fig. 57. TWIGS — Rather stout, zigzag, at first green and pubescent, later brownish to gray and smooth, decurrently ridged, enlarged at the nodes, marked by numerous, small, pale lenticels, encircled by stipule-scars. Pith wide and white. BTJDS — Alternate; terminal bud absent; sub-petiolar, surrounded by base of leaf -stalk or leaf- scars, J-jl of an inch long, conical, dull-pointed, very divergent from section of branch above end slightly from section below, covered with 3 scales, the outer one of which is smooth, shining, reddish-brown, the middle green and gummy, and the inner pubescent. LEAVES — Alternate, simple, broadly ovate, 3-5-lobed, toothed on margin, 4-10 inches across, bright green above, pale green and white woolly below. Petioles about 2 inches long, round, with enlarged hollow bases. Stipules 1* inches long, conspicuous, encircling twig. LEAF-SCARS — Alternate, 2-ranked, unequal in width, have a wavy outer margin, nearly encircle the buds at enlarged nodes of branches, fcrm an angle of about 60 degrees with the section of branch below, contain 5-10 bundle-scars which are arranged in a curved line and occur singly or in groups. FLOWERS — Appear m dense heads with the leaves in May. Staminate and pistillate flower heads occur on different stalks. Staminate are axillary and dark red; pistillate terminal, greenish and often tinged with red. FRUIT — Matures in October. Occurs solitary or rarely in 2s in brown heads about 1 inch in diameter suspended from a slender stalk. Heads often persist far into winter and are composed of many hairy achenes about i of an inch long. WOOD — Diffuse-porous; rays conspicuously broad; pores minute; hard, difficult to split, reddish-browr with ligh*: to {yellowish sapwood. Weighs 35.39 Ibs. per cubic foot. Used in the manufacture of furniture, interior furnishing, crates, tobacco boxes, and charcoal. DISTINGUISHING CHARACTERISTICS — The Buttonwood, also known as Buttonball, Syca- more, and Plane Tree, can readily be distinguished in summer by its massive form, its whitish, yellowish, or greenish bark of the upper branches which at times are covered with large, thin, dark brown scales of outer bark. The large leaves with their enlarged hollow- based petioles and the flowers in the form of neads, are also characteristic. In winter the massive form and wlutewashed appearance of the upper branches is distinctive. The smooth, reddish, sub-petiolar buds covered by a single exposed scale and surrounded by a leaf-scar with 5-10 bundle-scars will prevent one from confusing it with any other of our native species. The persistent fruit which usually occurs solitary is readily distinguished from the oriental species which bears its fruit in clusters of 2-4. RANGE — Maine and Ontario south to Florida, west to Minnesota, Nebraska and Texas. DISTRIBUTION IN PENNSYLVANIA— Common along streams, especially in the eastern, southern, and central parts of the State. HABITAT — Prefers moist, fertile soil, but will grow in rather dry soil. Best development in the moist valleys of the Ohio and Mississippi rivers. IMPORTANCE OF THE SPECIES — The wood of this species is annually becoming of more commercial importance and hence it should be planted at least to a limited extent. It may be grown from cuttings or from seed. It is planted sparingly for ornamental purposes but the Oriental Sycamore sc-eins to be preferred pince it is more attractive and less subject to fungous diseases. 176 THE PULSE FAMILY— LEGUMINOSAE. This is a very large family and contains many well-known trees, shrubs, and herbaceous plants. It comprises about 460 genera with 7,350 species of which number more than 100 genera with about 1,400 species are native to North America. The flora of Pennsylvania com- prises about 32 genera with approximately 90 species but only 4 spe- cies belonging to 4 different genera can be classified as trees. Some authors separate the members of this family into 3 distinct families known as: (1) The Mimosa family, Mimosaceae, (2) The Senna fam- ily, Caesalpiniaceae, and (3) The Pea family, Fabaceae. Many domestic and foreign plants which belong to this family are of considerable economic importance. Some of our native trees pro- duce very heavy, hard, and strong wood. They possess additional merits in that they grow rapidly and are well adapted to artificial propagation. Some of them, in particular the Common Locust, are subject to the attack of destructive insects and fungi. Some of the shrub members of this family are among the most attractive that one can find for ornamental planting. The herbaceous members com- prise some of the commonest and most valuable food and forage plants of the world, such as the peas, beans, clover, and the common peanut. Among the valuable products which some of the foreign members of this family produce one can mention Senna and Log- wood. Senna is prized on account of its laxative properties and is derived from the leaves of a few African species of Cassia. Log- wood, the most important of vegetable dyes, is derived from the heartwood of the trunk and roots of a tree growing in the West Indies and Central America. Indigo, one of our important and widely used dyes, is also obtained from a member of this family. The well-known Sensitive Plant (Mimosa pudica L.) so common in our greenhouses and a mere weed in the tropics is one of the most widely known and interesting representatives of this family. In addition they comprise a great number of plants which are important on account of the medi- cinal properties derived from them. Probably one of the greatest values which we can attach to some of the members of this family is the means which they have at their command for restoring nitrogen to barren land. If one examines the roots of clover, alfalfa, soy bean, or the Common Locust he may find little swellings or enlarge- ments upon them known as root tubercles. These swellings are caused by bacteria which possess the power of taking free nitrogen from the air and by means of complicated chemical changes passing it to members of this family. As a result these plants can be grown upon soils very deficient in nitrates. In addition they will return sufficient nitrogen to the soil so that companion or subsequent crops will thrive which would have barely existed without the nitrogen. The Common Locust often thrives on old abandoned mud-dams found 177 about ore mines while other more aggressive species fail even to es- tablish themselves. The members of this family are distinctly characterized by their fruit which matures in one season and usually resembles ordinary garden beans or peas. The fruit of some of the trees found in the western part of North America varies more or less from the typical bean-like fruit pod. The flowers of our native trees may be irregular in form, i. e. pea -like or bean-like, as in the Common Locust and Ked- bud, or regular in form as in the Honey Locust and Kentucky Coffee Tree. The two native tree-species with irregular flowers have also perfect flowers, i. e. flowers with both the male (pollen producing) and female (seed producing) organs in the same flo\ver while the other two native tree-species have regular but imperfect flowers, i. e. flowers with one sex so suppressed that only the other sex remains in each flower. Whenever the male and female flowers, also known as staminate and pistillate flowers respectively, occur separately, they may be found on the same branch, or on the same tree, or on different trees. The leaves of nearly all the tree members of this family are alternate and compound, but a few such as our native Kedbud have simple leaves. Some species as our Common Locust are normally only once compound, others as the Honey Locust may be once or twice compound, while still others, as the Kentucky Coffee Tree, may be normally twice compound. SUMMER KEY TO THE GENERA. Page. 1. Leaves simple; iwigj slender and unarmed, Cercis 180 1. Leaves compound; twigs stout or armed with spines or thorns, 2 2. Twigs very stout aud clumsy but not armed with spines or thorns; fruit-pods woody; leaves twice compound, from 1-3 ft. long, Gymnocladus 178 2. Twigs relatively sleiuler and armed with spines or thorns; fruit-pods leathery; leaves usually cnce or sometimes twice compound, rarely over 1 ft. long, 3 3. Flowers greenish, regular or nearly so, imperfect, in axillary spikes; leaves once or twice compound, even-pinnate; twigs, branches, and often trunks with long branched thornri Gleditsia 179 3. Flowers whitish, irregular, perfect in drooping racemes; leaves usually once com- pound, odd-pinnate; twigs often with two short spines at nodes, Robinia 181 WINTER KEY TO THE GENERA. 1. Twigs, branches, am? trunks usually armed with spines or thorns 2 1. Twigs, branches, and trunks without spines or thorns, 3 2, Twigs and branches armed with a pair of spines not exceeding i of an inch in length at each node; fruit-pods 2-4 inches long, & of an inch broad; bark reddish- brown, even on young trunks deeply furrowed, Robinia 181 2, Twigs, branches, and often trunks usually prmed with thorns which occur singly, are often branched and usually much exceed i of an inch in length; fruit-pods 10-18 inches long, 1-15 inches wide; bark ;jrayish-brown to black, not furrowed, often covered with conspicuous oblong lenticels, Gleditsia 179 3. Twigs stout, clumsy, blunt-pointed, with large conspicuous bundle-scars and large pink to brown pith; fruit-pods thick, woody, stubby, certain fleshy pulp and large seeds; buds silky-pubescent, depressed, uppermost one surrounded by incurved hairy ring of bark, Gymnocladus 178 3. Twigs slender, not clumsy nor blunt-pointed, with inconspicuous bundle-scars and pith with reddish longitudinal streaks; fruit-pods very thin, leathery, without fleshy pulp, an.l contain small seeds; buds smooth, not depressed, often somewhat flattened and sppressed, Cercis 180 12 178 KENTUCKY COFFEE-TREE. Gymnocladus dioica, (Linnaeus) Koch. GENUS DESCRIPTION — This genus comprises only 2 species, one Gymnocladus cbinensis a native of southern China, and the other described here. The generic name Gnymnocladus is of Greek origin and means "naked branch" referring to the stout clumsy branches which are devoid of foliage for about 6 months of the year. FORM — A medium-sized tree usually 40-80 ft. in height with a diameter of 1-2 ft. but may reach a height of 100 ft. with a diameter of 3 feet. Trunk usually short, soon subdividing into 2 or 3 secondary nearly parallel stems. Crown narrow obovate, composed of very stout branchlets. BARK — Of medium thickness, dark gray to dark brown, roughened by shallow fissures separat- ing low ridges covered with thin recurved scales. TWIGS — Very stout, blunt-pointed, greenish-brown, often coated with a whitish crusty film, occasionally covered with fine hairs, and marked with large conspicuous lenticels usually most numerous on the second year's growth. Pith large, pink to brown in color. BUDS — Alternate; terminal bud absent; small, downy, imbedded in twig so that it scarcely projects beyond surface, surrounded by incurved hairy ring of bark, superposed. The upper- most bud is the largest; the lowest is small and located in the depression at top of leaf -scar. LEAVES — Alternate, twice compound, 1-3 ft. long, 1J-2 ft. broad, with 7-13 foliate pinnae; 1-2 basal pairs of pinnae are reduced to entire leaflets. Pinnae have 3-7 pairs of leaflets. Leaflets ovate, 2-2J inches long, wefige-shaped to rounded at base, sharp-pointed at apex, entire to wavy on margin. LEAF-SCARS — Alternate, more than 2-ranked, large, conspicuous, raised on projections of twigs, broadly heart-shaped, paler in color than surrounding twig; contain 3-5 large, raised bundle-scars. FLOWERS — Appear about June. Regular, polygamus, or dioecious by abortion. Stamina te flowers greenish-white and arranged in a raceme-like corymb about 3-4 inches long. Pistillate flowers greenish-white and arranged in terminal racemes 6-8 inches long. FRUIT — A broad, flat, thick, stubby, reddish-brown pod, 4-10 inches long, 1-2 inches broad, sometimes covered with a grayish bloom. Pods often persist far into winter and remain closed. Seeds dark brown, flat, 6-9 to a pod, over J of an inch across, surrounded by a somewhat sticky sweet pulp. WOOD — Ring-porous; pores in spring wood large, in late wood small; rays distinct but not conspicuous; heavy, not hard, strong, coarse-gained, light brown to reddish-brown, durable in contact with soil; takes a fine polish. Weighs about 43 Ibs. per cubic foot. Used for fence posts, fence rails, and occasionally in construction. DISTINGUISHING CHARACTERISTICS— The Kentucky Coffee-tree, also known as Mahogany, Coffee Nut, and Nicker Tree, can be distinguished by its large twice compound leaves, its stout, clumsy, unarmed branches marked with large leaf-scars and containing pink to brown pith, and by its thick, stubby, and woody fruit-pods. The superposed, depressed, silky buds, the uppermost of which is surrounded hy an incurved hairy ring of bark, are also character- istic. In general it resembles the Ailanthus ')ut it can be distinguished from it especially by its curious bark, its characteristic fruit, and the parallelism of its primary branches. RANGE — Central New York south to Tennessee and westward to Minnesota and Indian Territory. It is absent from many localities within this range. DISTRIBUTION IN PENNSYLVANIA — Planted extensively as an ornamental tree but usually known under the name cf Mahogany. Franklin county is the only part of the State where it is reported as a native tree. HABITAT — Rich woods and bottomlands. Always occurs solitary, never in clusters or stands. Often only a single tree known in a locality. When planted it will grow practically anywhere in the State, IMPORTANCE OF THE SPECIES — This tree is of no commercial importance, especially in this State where it is very rare. It is regarded rather attractive as an ornamental tree and is planted extensively in this State. It loses its leaves early in autumn and develops them late in spring. PLATE XCIV. KENTUCKY COFFEE-TREE. 1. Staminate flowers, x J. 2. Pistillate flowers, x J. 3. Portion of a doubly compound leaf, x i 4. Fruit pods with portion of one pod removed showing two seeds, x J. 5. Section of a winter twig showing superposed and inconspicuous buds, lenticels, pith, and leaf- scars with bundle-scars, x 4. 6. Section of a winter twig, slightly enlarged. PLATE XCV. HONEY LOCUST. 1. Flowering branch with mature leaves, x \, 2. Section of a branch with fruiting pods and a branched thorn, x J. 3. A winter twig with thorns, x J. 4. A branched thorn, x \. 5. A leaf-scar, enlarged. 179 HONEY LOCUST. Gleditsia triacanthos, Linnaeus. GENUS DESCRIPTION — This genus comprises about 11 species of trees which are usually armed on the branches and trunk with simple or branched thorns. They are distributed in the temperate part of Asia and eastern North America. Fossil representatives of this genus have been reported from Europe. Three species are native to eastern North America, one inhabiting Texas, one the southern and south-central United States, and one described here. The generic name is in commemoration of the German botanist, John Gottlieb Gleditsch. FORM — A medium-sized tree usually from 40-50 ft. high with a diameter of 1-2 ft. but may reach a height of 140 ft. with a diameter of 4-6 feet. Trunk usually short but when, grown in very close stands may be rather clean and long. Crown broad, obovate, round-topped, high on account of lateral drooping branches. BARK — On young trunks smooth covered with many, very conspicuous, raised, oblong lenticels; on old trunks grayish-brown to almost black, sometimes smooth but usually roughened by a few fissures and thick, firm, broad ridges with projecting edges. Bark on trunks is often covered with many thorns. See Figs. 59 and 94. TWIGS — Eather stout, zigzag, smooth, glossy, with enlarged nodes; greenish-red to brown, covered with few, small, scattered lenticels which become larger in time; pith thick and white. Twigs frequently bear thorns which are often branched and contain reddish-brown pith. BUDS — Alternate; terminal bud absent; small, usually 3-5 at a node, placed one above another; upper ones scaly and visible, lowest one not scaly, nor visible except as a dot. Some buds are slow in de^ eloping. LEAVES — Alternate, singly or doubly compound, 7-8 inches long. Petioles flattened, grooved above, enlarged at base. When singly compound with 18-28 leaflets; when doubly compound with 8-14 pinnae and each with usually 18-20 leaflets. Leaflets lanceolate-oblong, 1J-2 inches long, rounded at the base and apex, somewhat serrate on margins. LEAF-SCARS — Alternate, 2-ranked or more than 2-ranked, U-shaped; varying in width; broadest about the 3 bundle-scars and narrower between. FLOWERS — Appear about May or June. Polygamus, small, greenish. Staminate flowers arranged in short hairy racemes with short stalks. Pistillate flowers in few-flowered, rather elongated and solitary racemes. FRUIT — A more or less twisted, flat, and reddish-brown pod, 10-18 inches long, containing many flat, oval, brownish seeds. The pods are thin, do not split open, often persist into winter, and occasionally are produced in large numbers. WOOD — Ring-porous; rays conspicuous on account of their brilliancy; hard, strong, heavy, durable in contact with the soil; heartwood bright reddish-brown with thin pale sapwood. Weighs about 42 Ibs. per cubic foot. Used mainly for fence posts and rails, hubs of wheels, and general construction. In time its use will be extended and it may be grown for timber. DISTINGUISHING CHARACTERISTICS— The Honey Locust, also known as the Sweet Locust, Thorn Tree, Three-tkorned Acacia, and Honey Shucks, can be distinguished by its large branched thorns located above th«> leaf-scars. A thornless variety is, however, known. The once-com- pound or sometimes twice-compound evenly-pinnate and alternate leaves together with the leathery fruit pod from 10-18 inches long and the grayish-brown to black bark often covered with conspicuous oblong lenticels are also characteristic. A longitudinal section of a twig just above the origin of a leaf or a leaf -scar will usually show five separated and superposed buds, the upper scaly and externally visible, the lowest not scaly and hidden beneath the bark. RANGE — Ontario through Pennsylvania to Florida, westward to Kansas and Texas. DISTRIBUTION IN PENNSYLVANIA— Found as a native or planted tree in all parts of the State. Its original distribution in this State was limited almost entirely to the region west of the Allegheny Mountains, except a few local outposts east of them. At present it is common as a planted tree in tho entire eastern portion of the State and in many places has escaped cultivation. HABITAT — It develops best in rich soil along moist river bottoms but will grow in any fertile soil which is not too wet. It demands plenty of light. IMPORTANCE OF "THE SPECIES — This tree is of little commercial importance as a timber tree in Pennsylvania because it is limited in its distribution. Most of the existing trees of this State are open grown and not forest grown, therefore, too knotty to be of any commercial value. If properly planted it will produce excellent wood. It grows rapidly, is free from insect and fungal enemies, has an attractive form, and bears graceful foliage. The leaves come out late in spring jind, hence, it is not of much value for shade. 180 REDBUD. Cercis canadensis, Linnaeus. GENUS DESCRIPTION — This genus comprises 7 species of small trees and shrubs found In parts of Asia, Europe and North America. Three species are native to North America, 1 inhabiting California, 1 Mexico aiid Texas, and 1 eastern United States. The lattei is native to Pennsylvania and described here. They are prized mainly on account of their ornamental value due to their bright rose-colored, pea-like flowers which cover the branches with a profuse and brilliant Same of color in early spring before the leaves come out. FORM — A small tree usually about 15-20 ft. high with a diameter of 6 inches but may reach a height of 50 ft. with a diameter of 18 inches. Trunk short bearing rather upright branches which form a shallow and broad crown. BARK — Thin, shallowy fissured separating ridges which peel off into numerous scales, reddish- brown to very dark brown. See Fig. 56. TWIGS — Slender, smooth, light brown, becoming grayish-brown, covered with numerous very small lenticels, containing pith which sometimes has reddish longitudinal streaks. BUDS — Alternate; terminal one absent; small, J of an inch long, blunt-pointed, dark purplish- red, spherical or somewhat flattened when appressed. Sometimes superposed with upper one usually the larger, or clustered at the base of a lateral branch, covered with 2-3 visible scales with hairy margin. LEAVES — Alternate, simple, rounded or heart-shaped, 3-5 inches long, conspicuously 5-7 nerved, cordate at base, pointed at apex, entire on margin. LEAF-SCABS — Alternate, 2-ranked, inversely triangular to heart-shaped, somewhat raised, containing 3 conspicuous bundle-scars. Short spreading ridges often originate at outer margin of the leaf-scars and extend down the stem for a short distance. FLOWERS — Appear ir March or April before the leaves or sometimes when the leaves are just appearing. Resemble the sweet pea in form; perfect anc! brilliant red, borne usually in clusters of 4-8, often developing from buds located at the base of lateral branches as well as from buds located along the branches. FRUIT — A small, rose-colored to light brown, short-stalked pod, 25-3 inches long, about 3 of an inch wide, containing about 6 broadly ovate, flattened, light-brown seeds. Pods may persist until early winter and are often produced in enormous quantities. WOOD — Ring-porous; heavy, hard, not strong, rich dark reddish-brown with light sapwood. Weighs 39.65 Ibs. per cubic foot. Not found on the market. DISTINGUISHING CHARACTERISTICS— The Redbud, also known as the Judas Tree, can be distinguished by its simple alternate and heart-shaped leaves, its slender unarmed and light brown twigs with reddish-streaked pith, its small, thin, leathery fruit-pods, and its perfect, pea-like, brilliant red blossoms which occur in clusters of 4-8, appearing in early spring before the leaves i=nd developing from a cluster of buds located at the base of a lateral branch as •well as from buds located along the twigs. This is the only tree native to this State which develops a cluster of purplish flower buds on a branch just below the origin of a lateral twig. RANGE — Ontario through New Jersey to Florida, westward to Minnesota and Arkansas. DISTRIBUTION IN PENNSYLVANIA— Not known to occur in the northern or eastern parts of the State. Reported from the southeastern, southern, central and western parts. Common In the Schuylkill and Perkiomen Valleys and along parts of the Susquehanna River Valley, especially northwest aud southeast of Harrisburg. Common about Gettysburg, and south of Chambtrsburg in the Cumberland Valley. Occurs in a dense pure stand covering about one acre southwest of Gettysburg. HABITAT — Prefers rich moist soils. Common in abandoned fields, cut-over and open wood- lands. Also found in the understory of the forest. Endures shade but prefers plenty of light. IMPORTANCE OF THE SPECIES — This tree is of no commercial importance as a forest tree but where a tall shrub or a small tree is desired for ornamental planting hardly a more attractive one could be found. It has a pleasing form at all seasons of the year, an exceptionally beautiful and abundant bloom in spring before the leaves com* out, and in addition, grows rapidly. It is cultivated extensively in Europe as an ornamental tree. PLATE XCVI. REDBUD. 1. A flowering branch, x | 2. A single flower, x |. 3. A single stamen, enlarged. 4. A single pistil, enlarged. 5. A pistil with the ovary sectioned so as to show the ovules, enlarged. «. A fruiting branch, x J. 7. An opened pod showing the seeds, x i. 8. A winter twig, x \. 9. Section of a winter twig, enlarged. 10. Portion of a winter twig showing location and arrangement of buds enlarged PLATE XCVII. COMMON LOCUST. 1. A flowering branch, x j. 2. A fruiting branch, x J. 3. A winter twig, x J. 4. Section of a winter twig, enlarged. 5. Section of a winter twig, enlarged. 181 COMMON LOCUST. Robinia Pseudo-Acacia, Linnaeus. GENUS DESCRIPTION — This genus comprises 7 species of tiees and shrubs native only to North America but some are planted extensively in Europe. Three of the 7 species reach tree- sissc while the others remain shrubs. The generic name is in commemoration of the French botanist Jean Robin and his son Yespasien. FORM — A medium-sized tree usually 30-45 ft. high with a diameter of 1-1J ft. but may reach a height of 75 ft. with a diameter of 2-2J feet. Forest grown specimens are often straight, clean, nml free fiom branches for 3 of height of tree. Open grown specimens usually branch low. Crown usually uarrow, oblong, ani open. BARK — On both young and old trunks rough, reddish-brown, deeply furrowed, with high rather rounded ridges which do not peel off in scales; sometimes 1-1 \ inches in thickness. See Fig. 83. TWIGS — Rather stout, brittle, more or less zigzag, round to angular in cross-section, sometimes ridged, greenish to reddish-brown; often bearing two spines at a node, covered with a few pale lenticels, pith white and often angular. BUDS — Alternate; terminal one absent; small, 3-4 superposed, imbedded in twig under leaf- scar in a rusty somewhat hairy cavity. Their position is hardly visible in winter but becomes evident in spring when growth starts. LEAVES — Alternate, compound, 8-14 inches long; petioles slender, grooved on top, and swollen at the base. Leaflets odd in number and stalked, ovate to oblong, 7-9 In number, 1-2 inches long, usually rounded at apex and base, entire on margin. LEAF-SCARS — Alternate, more than 2-ranked, rather large and conspicuous, Irregular in out- line, covering the buds; often located between two prickles which are developed and hardened stipules; contain 3 bundle-scars. FLOWERS — Appear about May after the leaves or occasionally before the leaves, resembling the blossom of a pea. Perfect, cream-white, about an inch r cross, fragrant, borne on slender stalks about I of an inch long, arranged in loose drooping racemes 4-5 inches long. FRUIT — A small, dark brown, and thin pod, 2-4 inches long and J of an Inch wide; usually con- taining from 4-8 small dark brown mottled seeds. The pods often persist far Into winter. WOOD — Ring-porous; rays quite distinct especially on radial section; heavy, very hard and strong, very durable in contact with the soil, yellowish -brown to cherry-red or reddish-brown with thin greenish or yellowish sapwood. Weighs about 46 Ibs. per cubic foot. Used extensively In former time for ship building, and at present for posts, in turnery, for tree nails, insulator pins and fuel. DISTINGUISHING CHARACTERISTICS — The Common Locust, also known as the Black Locust, Yellow Locust, White Locust, Locust, and Acacia, may be distinguished by Its droop- ing racemes of white Irregular flowers, its odd-pinnate compound leaves, its twigs with two short spines at a node, its 2-4 inches long leathery fruit pod and its deeply furrowed reddish- brown bark. The leaf-scars located between the two spines when present and covering 3-4 rusty downy superposed buds are also charactertistic. The characteristic coloration of the foliage of this tree when attacked by the Locust Leaf Miner ami the characteristic swelling of the branches when attacked by the Locust Borer aid in recognizing it. The presence of the fruiting body of the Locust Rot (Femes rimosus) so common in southern Pennsylvania, is a sure means of identifying the tree. RANGE — Mountains of Pennsylvania, south to Georgia, westward to Iowa and Kansas. Naturalized over an extensive area in America and widely planted in Europe. DISTRIBUTION IN PENNSYLVANIA— Originally it was found only in the central and south- ern portions of the Allegheny Mountains in this State. At present it is found all over the State as an ornamental tree or in fence rows and in many places it has escaped into the forest and abandoned fields. HABITAT — Grows vigorously on moist fertile soil, especially on rich bottomlands and along mountain streams. Also grows on rather rocky and sterile mountain slopes. Frequent on abandoned charcoal hearths and mud-dams found near ore mines. IMPORTANCE OF THE SPECIES — The real importance of this tree Is somewhat In doubt. It produces excellent wood and grows rapidly in some localities, especially where It Is free from enemies. Two insects, known as Locust Borer and Locust Leaf Miner, and a fungus known as the Locust Rot (Fomes rimosus), are doing enormous damage to this tree locally. In regions where these enemies are wanting and where suitable soil and climate are at band it may be advisable to plant this tree especially when posts, poles, or ties are desired. It baa very attractive flowers which may appear before, with, or after the leaves. 182 THE CASHEW FAMILY— ANACARDIACEAE. This family contains a large number of small trees and shrubs and a few woody climbers widely distributed over the world, but most abundant in the tropics. Many of the representatives of this family are noted for their acrid, resinous, or milky juice which makes th,em of considerable value in medicine, tanning, and the manufac- ture of varnishes and resins. About 50 genera with 500 species belong to this family. North America has few representatives. Only 3 genera with tree repre- sentatives are embraced in its flora. The genus Rhus is the only one native to northeastern America. It has representatives in Pennsyl- vania. THE SUMACHS— RHUS, Linnaeus. The Sumachs comprise a large number of trees and shrubs which are widely distributed. About 120 species are known of which num- ber about 16 species are native to North America and 6 to Pennsylva- nia. Most of the species of this genus are found in South Africa. All have large pithy twigs and a milky, sometimes poisonous, sticky juice. The leaves of all are alternate. One species alone is ever- green and one other has simple leaves. All others are deciduous and have compound leaves. Three of the 6 species native to Pennsylvania reach tree-size. The others are mere shrubs. The Poison Ivy or Poison Oak (Rhus Toxi- codendron L.) is very abundant along fences and by roadsides. Its stem often trails along the ground and sends up short branchlets which bear the compound leaves with 3 leaflets. The leaves are poisonous to the touch. The Smooth Sumach (Rhus glabra L.) is a low-growing and spreading shrub sometimes becoming a small tree. It has glabrous branchlets which are more or less glaucous. It has compound leaves with 11-31 leaflets. It is very common in abandoned fields and seems to thrive on sandy soil. The Fragrant Sumach (Rhus canadensis Marsh.) reaches a height of 2-6 ft. It has compound leaves with 3 leaflets which are aromatic when crushed. The Smoke-Tree (Rhus Cotinus L.) is one of the commonest plants of our gardens and lawns. It is an introduced species com- ing from Europe and warm-temperate Asia. Locally it has escaped cultivation. 183 SUMMER KEY TO THE SPECIES. Page. 1. Leaf -petioles winged; leaflets with entire margins except near apex, ..R. copallina 186 1. Leaf -petioles not winged; leaflets either with entire or serrate margins, 2 2. Leaflets 7-13, with entire margins H. Vernix 184 2. Leaflets 11-31, with serrate margins, 3 3. Leaflets glaucous beneath; twigs smooth; shrubs, R. glabra 183 3. Leaflets not glaucous beneath; twigs densely hairy; small trees R. typhina 185 WINTER KEY TO THE SPECIES. 1. Terminal bud present; fruit white, smooth, in loose, drooping, grape-like clusters frequents swamps; leaf -scars broad, do not encircle buds; juice poisonous, .... R. Vernix 184 1, Terminal bud absent; fruit red, hairy, in compact erect clusters; frequents dry soils; leaf -scars encircle or almost encircle buds; juice not poisonous, 2 2. Twigs stout, with watery juice; leaf-scars broadly crescent-shaped R, copallina 186 2. Twigs very stout, with milky juice; leaf -scars narrower 3 3. Twigs densely hairy, R. typhina 185 3. Twigs smooth R. glabra 182 184 POISON SUMACH. Rhus Vernix, Linnaeus. FORM — A shrub to small tree, usually 5-10 ft. high but may reach a height of 20 ft. with a diameter of 8 inches. Usually branches near ground. Crown wide, deep, and usually rounded. BARK — Smooth, somewhat streaked, thin, light to dark gray, roughened with horizontally- elongated lenticels. TWIGS — Stout, orange-trown, later light gray, smooth, often glossy, covered with numerous raised lenticels, contain yellowish-brown pith; if punctured or cut, exude watery juice which turns yellow upon exposure. BUDS — Alternate; terminal bud present and larger than lateral ones; purplish, conical, acute, about 1/5-3/5 of an inch long, covered with a few scales which are downy on back and margin. LEAVES — Alternate, compound, 7-14 inches long, with wingless petiole, and with 7-13 leaflets, obovate, 3-4 inches long, acute at apex, wedge-shaped at base, entire-margined, dark green and shiny above, pale below. LEAF-SCABS — Alternate, large, broad, conspicuous, do not encircle buds, upper margin straight or nearly so, contain numerous bundle-scars which are scattered or arranged in a curved line. FLOWERS — Appear about June or July. Staminate and pistillate flowers borne on different plants. The small yellowish-green flowers are arranged in long, drooping, rather narrow panicles. FRUIT — A small, spherical, glossy, Ivory-white to yellowish-white drupe arranged In loose, drooping, grape-like clusters. It Is about 1/5 of an inch in diameter, slightly compressed and often persists far into winter. Ripens about September. Pistillate trees alone bear fruit. WOOD — Ring-porous; brittle, soft, coarse-grained, light yellow in color. Weighs 27.31 Ibs. per cubic foot. DISTINGUISHING CHARACTERISTICS — The Poison Sumach, also known as Poison Oak, Poison Dogwood, Poison Elder, and Swamp Sumach, can be recognized in winter by its alternate buds with the terminal bud present, its broad leaf-scars which do not encircle the bud and its smooth and rather stout branchlets. The white berry-like fruit arranged in drooping clusters often per- sists far into winter. The leaves are compound, without winged petioles and have from 7-13 shiny leaflets with entire margin which turn to a brilliant scarlet or orange in autumn. This species is usually found in swamps. RANGE — Ontario, south to Florida, west to Minnesota and Louisiana. DISTRIBUTION IN PENNSYLVANIA— Occasional and local in the eastern, southern and central parts. Rarer in other parts. HABITAT — Prefers low grounds and swamps. Occasionally found on moist slopes. IMPORTANCE OF THE SPECIES — This shrub or small tree is one of our most poisonous plants. The wood which it produces is of no commercial importance. Some people are entirely Immune to its poisonous principles, while others are affected by it upon handling it while a few need only to walk by it. It is claimed all traces of the poison can be removed by washing the, parts thoroughly with a saturated alcoholic solution of acetate of lead immediately or a few hours after the contact. Pure alcohol is also valuable as a wash if applied shortly after contact. PLATE XCVIII. POISON SUMACH. 1. Branch with immature and mature leaves, and a stamiuate flower panicle, x 2. A pistillate flower panicle, x J. 3. A section of a branch with two drooping clusters of fruit, x J. 4. A single fruit, enlarged. 5. A winter twig, x J. 6. An axillary bud and a leaf -scar with bundle-scars, enlarged. PLATE XCIX. STAGHORN SUMACH. 1. Branch with a flower panicle and mature leaves, x i. 2. A staminate flowei, enlarged. 3. A pistillate flower, enlarged. 4. An erect cone-like fruit cluster, x J. 5. A single hairy fruit, enlarged. 6. A hairy winter twig, x J. 7. A bud almost surrounded by a leaf -scar with bundle-scars, enlarged. 8. A leaf-scar, enlarged. 185 STAGHORN SUMACH. Rhus typhina, Linnaeus. FORM — A shrub or small tree usually reaching a height of 10-20 ft. but may reach a height of 40 ft. with a diameter of 15 inches. Trunk usually short, bearing a broad flat-topped crown. Lateral branches are decidedly ascending. BARK — On old trunks rough, dark brown, sometimes scaly; on younger trunks and branches smooth, thin, somewhat papery, covered with numerous lenticels which later develop into rough dots. Rich in tannin. TWIGS — Covered, for 3 years with brown to black velvety pubescence, later smooth, stout, clumsy; if cut or punctured exude a milky juice, which turns black upon exposure. Twigs are often frozen back in winter, covered with conspicuous orange-colored lenticels, and contain a large yellowish-brown pith. BUDS — Alternate; terminal bud absent; conical, spherical obtuse, covered with dense rusty hairs. LEAVES — Alternate, compound, 16-24 Inches long, with stout wingless petiole and 11-31 leaflets. Leaflets oblong, 2-5 inches long, nearly sessile, acute at apex, serrate on margin, rounded or heart-shaped at base; when mature smooth, dark green above, and pale beneath. LEAF-SCARS — Alternate, nearly encircle bud, large, conspicuous, U-shaped, contain scattered bundle-scars sometimes grouped in 3s. FLOWERS — Appear in May or June. Occur in dense yellowish-green panicles. Staminate panicles are about 8-12 inches long and 5-6 inches broad. Pistillate panicles are only 5-8 inches long but more compact. FRUIT — Arranged in compact, erect, cone-like, red clusters which are 5-8 inches long, 2-3 inches broad and persist far into winter. Only plants bearing pistillate flowers produce fruit. The single fruit is a spherical drupe covered with red hairs and contains a small hard seed. Sumachs with red fruit are not poisonous. WOOD — Ring-porous; brittle, soft, orange-colored, streaked with green, rather satiny to touch. Sapwood broad and white. Weighs 27.15 Ibs. per cubic foot. Used for manufacture of spiles, cups, napkin rings, and balls for darning stockings. DISTINGUISHING CHARACTERISTICS — The Staghorn Sumach, also known as Velvet Sumach, can be distinguished from all our native Sumachs by its velvety pubescent twigs. The Smooth Sumach (Rhus glabra L.) is usually smaller and has its twig covered with' a bloom, but not with pubescence. The Dwarf Sumach (Rhus copallina) has winged petioles and a watery juice while the Staghorn Sumach has no winged leaf-petioles but has a milky juice. The Poison Sumach has a terminal bud, white drooping fruit, entire leaf-margins, leaf-scars which do not encircle buds, and frequents swamps, while the Staghorn Sumach has no terminal bud, has red and erect fruit clusters, serrate leaf-margins, leaf-scars which almost encircle buds, and frequents dry soils. RANGE — New Brunswick to Minnesota, and southward to Georgia and Alabama. DISTRIBUTION IN PENNSYLVANIA— Locally throughout the State. Very common in eastern and southern parts. Rarer in northern and western parts. HABITAT — Usually found on fertile dry upland soil. Rarer on border of swamps and streams. Frequents abandoned fields and fences. IMPORTANCE OF THE SPECIES— This species is of little commercial importance. The wood is rarely used. The bark of the stem and roots, and the leaves are rich in tannin. It Is occasionally planted for ornamental purposes. 186 DWARF SUMACH. Rhfls copallina, Linnaeus. FORM — A small shrub rarely ^more than 6-8 ft. tall, becomes a tree only in Arkansas and Texas. BARK — Rather thin, light to reddish-brown, often smooth; on older specimens may peel off into papery layers, frequently roughened by large, elevated, brownish projections. TWIGS — At first hairy, somewhat zigzag and greenish-red; later smooth, reddish-brown, and roughened by prominent leaf -scars and large dark-colored lenticels; frequently roughened by large elevated rugosities. BUDS — Alternate; terminal bud absent; axillary, small, spherical, covered with rusty brown pubescence. LEAVES — Alternate, compound, 6-12 inches long, with winged petioles and 9-21 leaflets. Leaflets ovate-lanceolate, acute at apex, often unequal and wedge-shaped at base, entire on margin except near apex where a few serrate teeth may be found, usually smooth above and pubescent below. LEAF-SOARS — Alternate, broadly crescent-shaped to inversely triangular; partly surround buds; contain a few clusters of bundle-scars often occurring in 3s. FLOWERS — Appear about July. Produced in axillary or terminal panicels. Staminate and pistillate usually occur on different plants. FRUIT — Matures about 5-6 weeks after flowers. Usually arranged in dense, stout, pubescent, often persistent, red clusters. The individual fruit is spherical, about J of an inch across, covered with a hairy red coat and contains a smooth orange-colored seed. WOOD — Diffuse-porous; soft, coarse-grained, light brown, richly striped with yellow and black. Weight and uses are about the same as the Staghorn Sumach. DISTINGUISHING CHARACTERISTICS— The Dwarf Sumach, also known as Mountain Sumach can be distinguished from our other native species of Sumach by its winged leaf-petioles and its leaflets which are entire-margined except near the apex. Its branches contain a watery juice while the branches of the Staghorn and Smooth Sumach contain a milky juice. Its branches are smooth while those of the Smooth Sumach are covered with a bloom and those of the Staghorn Sumach with a velvety pubescence. It has neither terminal buds nor white fruit like the Poison Sumach. RANGE— Maine to Florida, west to Nebraska and Texas. DISTRIBUTION IN PENNSYLVANIA— Local, often common, throughout the State. HABITAT — Common on dry hillsides and ridges. Occasional on rich bottomlands. Frequents abandoned fields. IMPORTANCE OF THE SPECIES— The Dwarf Sumach is merely a shrub east of the Mis- sissippi and consequently of no commercial importance. It may be utilized in landscape gar- dening on account of its dwarf form and attractive autumnal foliage. It reaches tree-size in Arkansas and Texas, PLATE C. DWARF SUMACH. 1. Branch with mature leaves with winged rachises, 2. A branch with an erect cluster of fruit, x J. 3. A single hairy fruit, enlarged. 4. A winter twig, x J. 5. A leaf-scar with bundle-scars, enlarged. and a panicle of flowers, x PLATE CI. TREE OF HEAVEN. 1. A mature leaf, x |. 2. Lower side of two leaflets showing glands, x £. 3. A panicle of flowers, x \. 4. A small cluster of winged seeds, x \. 5. A seedling, x J. 6. A winter twig, x J. 7. A bud and a leaf-scar with bundle-scars, natural size. 187 TREE OF HEAVEN. Ailanthus glandulosa, Desfontaines. FAMILY AND GENUS DESCRIPTION— The Quassia family, Simarubaceae, comprises about 30 genera with 150 species found mostly in the tropics and the warmer parts of both the east- ern and western hemispheres. Three genera, each with 1 tree species, are native to the south- ern part of the United States. A single species of a fourth genus has been introduced from China. This genus, Ailanthus, contains 7 species all native to eastern Asia. No member of this family is native to Pennsylvania. FORM — May reach a height of 100 ft. with a diameter of 3 ft., but usually much smaller. Trunk usually short, but sometimes long, bearing stout branches with few branchlets. Crown wide, high, and flat-topped. BARK — On younger trunks smooth, thin, light gray, somewhat roughened with fissures. Ridges usually dark and stand in strong contrast with the light fissures. On old trunks thin, close, roughened with diamond-shaped fissures, dark gray and sometimes black. See Fig. 99. TWIGS — Stout, clumsy, yellowish-green to reddish-brown, covered with a fine velvety down and numerous, longitudinally-elongated, ochre-colored, scattered lenticels. Pith large, rather hard, light brown. When broken or crushed the twigs give forth a rank smell. Longitudinal striations may appear after outer covering of twigs scales off. BUDS — Alternate; terminal bud absent; false terminal bud often present; reddish-brown, downy, about 1/8-1/6 of an inch long, located In notch of upper surface of the leaf-scar, covered with scales; the two outer scales do not quite cover the bud, hence they leave a narrow slit running parallel with the twig. LEAVES — Alternate, compound, li-3 ft. long, composed of 11-41 leaflets. Leaflets ovate- lanceolate, 3-5 inches long, acuminate at apex, truncate to heart-shaped at base, almost entire with a few coarse teeth towards the base of the -leaf. Glands may be present on the lower side of the leaflets near or on the small basal lobes. LEAF-SCARS — Alternate, large, conspicuous, more than 2-ranked, heart-shaped, lighter In color than twig, have raised margins and contain about 8-14 conspicuous buridle-scars arranged in a V-shaped line. Bundle-scars sometimes curved or compounded. FLOWERS — Appear about June when leaves are fully developed. Stamina te and pistillate flowers occur on separate trees. Individual flowers small, green, and arranged In terminal panicles. The staminate have a very unpleasant odor. FRUIT — Borne only on female or pistlilate trees in conspicuous clusters which often persist far into winter. Each fruit consists of a spirally twisted wing about 1J inches long and 5 of an inch wide, in the center of which a small seed is located. WOOD — Ring-porous; with conspicuous rays; white to pale yellow, light, soft, weak, and open- grained. Used in cabinet work, for wooden ware, and for charcoal. DISTINGUISHING CHARACTERISTICS— The Tree of Heaven, also known as Paradise Tree, Ailanthus, Haven-Wood and Chinese Sumach, can be distinguished in winter by its stout twigs which are coversd with fine down and conspicuous scattered lenticels, and contain a large light brown pith; twigs are roughened by large heart-shaped leaf-scars containing a curved line of bundle-scars. The small gaping downy buds situate in the notch on the upper surface of the leaf-scars, are also characteristic. In summer the large alternate leaves with 11-41 leaflets which often have glands on the lower surface, are distinctive. The bark cannot be confused with that of any native tree. RANGE — Native of China. Widely planted In Ontario, Canada and the northeastern United States. Frequently it has escaped cultivation and is found in abandoned fields, in forest borders, and along fences. DISTRIBUTION IN PENNSYLVANIA— Naturalized extensively in the eastern, southern, cen- tral and western parts of the State. Escaped cultivation in many places. Thickets of it are found in Franklin county. In some places it is not only found in the open fields and along fences but is migrating into the forest with the hardwoods and pines. HABITAT — Tolerates almost any kind of soil and dense shade. Its rapid growth often enables it to dominate over its associates. IMPORTANCE OF THE SPECIES — This tree is of no special importance as a forest tree and has serious demerits as a shade or park tree. It was introduced into England about 1751 by missionaries and from there it was soon brought to America and first planted near Philadelphia. At first it was a very popular tree, but it soon lost favor. The staminate flowers are very 111 smelling. The wood is inferior in quality. The rapid and free growth of the root sprouts makes it almost impossible to eradicate it when once established. Its aggressive migration Into fields and forest is undesirable. 188 • AMERICAN HOLLY. Ilex opaca, Ait. FAMILY AND GENUS DESCRIPTION— The Holly family, Aquifolinceae, comprises 3 genera with about 290 species of small trees and shrubs distributed in temperate and tropical regions. Two genera. Ilex and Nemopanthus, are native to Pennsylvania. The former genus is repre- sented by 5 species and the latter by 1 species. Two of the 5 species of the genus Ilex are described below. The Mountain Holly, Nemopanthus mucronata, is usually a shrub rarely over 10 ft. in height. FORM — Usually a small tree reaching a height of 15-30 ft., but may attain a height of 50 ft. with a diameter of 3 feet. It is small in the North, but becomes larger in the South. Trunk short and bears slender, spreading and ascending branches which form a conic crown. BARK — Close, white or grayish or yellowish-brown, up to J of an inch in thickness, becoming rough with age. TWIGS — Rather slender finely rusty hairy but soon become smooth and light brown, covered by a few inconspicuous lenticels. , BUDS— Alternate; terminal one present and pointed; lateral ones are short, blunt-pointed, and somewhat downy. LEAVES — Alternate, simple, evergreen, thick, mostly smooth, flat, oval, with wavy margin and spiny teeth. Petioles are short, stout, and often hardy. Midrib is very prominent on the lower surface of the leaf. LEAF-SCARS — Alternate, semi-oval, rather conspicuous, with raised margin containing solitary bundle-scars. FLOWERS — Appear from April to June. The staminate and pistillate usually occur on different trees. The staminate are 2-9 on a common stalk while the pistillate are usually solitary. FRUIT — A bright red drupe, about the size of a pea, smooth, shining, persisting far into winter; containing a light brown nutlet with usually 4 ribs. WOOD — Diffuse-porous; with distinct and colorless medullary rays; chalky-white in color, medium in weight, hard, tough, not strong, close-grained. Weighs 36.26 Ibs. per cubic foot. Used in turnery, cabinet making and interior finishings, and for keys in pianos and organs. DISTINGUISHING CHARACTERISTICS— The American Holly, also known as Holly or White Holly, can be distinguished at any season of the year by its unique leaves, which are thick, flat, and oval, have wavy margins with scattered spiny teeth and persist for 2 or more years. Branches, bearing these unique leaves, are sold extensively about Christmas in most of our northern markets. The small red fruit, often persisting far into winter, is also distinctive. In cultivation one often finds the closely related European Holly (Ilex Aquifolium) which has leaves of a deeper green and with more wavy margins which have translucent edges. The berries of the European species are deeper red in color. RANGE — Maine, through Pennsylvania to Florida, westward to Indiana, Missouri and Texas. DISTRIBUTION IN PENNSYLVANIA— Very rare and local. Found in the following counties: Bucks, Dauphin, Delaware, Chester, Franklin, Lancaster and York. Only one specimen is known to grow wild in Franklin county. HABITAT — Usually found in moist soil near water. Prefers shelterd and shaded situations. IMPORTANCE OF THE SPECIES — The American Holly does not produce any wood of com- mercial importance in this State. Immense quantities of branches, bearing the unique and attractive leaves and bright red berries, are used for decorative purposes during the Christmas season. It is occasionally planted for ornamental purposes because it is very beautiful, but one should remember that it grows slowly, PLATE CII. AMERICAN HOLLY. 1. A pistillate flowering branch, x 1. 2. A staminate flowering branch, x 5. 3. A fruiting branch, x \. 4. Cross section of a fruit, enlarged. 5. Longitudinal section of a fruit, enlarged. 6. Section of a twig, enlarged. PLATE CIII. LARGE-LEAVED HOLLY. 1. A pistillate flowering branch, x i. 2. A staminate flowering branch, x i. 8. A fruiting branch, x 5. 4. A winter twig, x i. 5. Section of a winter twig, enlarged. 189 LARGE-LEAVED HOLLY. Ilex monticola, Gray. FORM-£-A shrub or small tree usually less than 20 ft. in height but may reach a height of 40 ' ft. with a diameter of 12 inches. It reaches its largest size in North and in South Carolina. Trunk short, bearing a rather wide and deep crown formed by slender, spreading, ascending branches. BARK — Thin, light brown, rough, warty, covered with numerous lenticels. TWIGS — Smooth, reddish-brown, becoming dark gray, enlarged at nodes; with decurrent ridges running down from leaf -scars; round, marked by many small lenticels at first indistinct but later conspicuous. Pith round, narrow, light yellowish-green. BUDS — Alternate, terminal bud present; lateral buds often superposed and covered with gaping scales; broadly ovate to globular, small, about J of an inch long, sharp-pointed or occasionally blunt-pointed. Bud-scales ovate, keeled, sharp-pointed, light brown, finely hairy at apex. LEAVES — Alternate, simple, deciduous, 4-5 inches long, J-2 inches wide, ovate or lanceo- late-oblong, taper-pointed at apex, sharply serrate on margin, tapering or rounded at base, thin, smooth, dark green above, paler below. LEAF-SCARS — Alternate, elliptical to broadly triangular, very small, inclined to twig. Bundle-scars solitary, lunate to almost circular. FLOWERS — Appear on short lateral stalks about June, when the leaves are almost developed; white or nearly so, small, about 4 of an "inch across. Staminate clustered, borne upon pedicels about 2/5 of an inch long; pistillate solitary or few in a cluster, on very short pedicels. FRUIT — Matures about September. Bright 'Scarlet, globose, about 2/5 of an inch in diameter containing 4-6 nutlets; nutlets narrowed at the ends, striate, prominently many-ribbed on the back. WOOD — Diffuse-porous; hard close-grained, nearly white. In general resembles that of the American Holly, page 188. Weighs about 41 Ibs. per cubic foot. Not found on the market. DISTINGUISHING CHARACTERISTICS— The Mountain Holly may be distinguished b{y its small size, its small clustered white flowers, \ts bright scarlet globose clustered fruit with striate many-ribbed nutlets, its ovate or lanceolate-oblong, smooth, sharply-serrate, dark green deciduous leaves, its small leaf -scars with a solitary bundle-scar, and its bitter reddish- brown twigs marked by many small lenticels and decurrent ridges below the leaf-scars. The closely related Black Alder or Winterberry (Ilex verticillata; has many characteristics in common with this species but may be distinguished by its smooth and even nutlets, its flowers which are all short-stalked, its leaves which are more downy on the lower surface. RANGE — New York to Georgia and Alabama. DISTRIBUTION IN PENNSYLVANIA— Rather common in the mountainous parts of the State. Rare or absent in other parts. HABITAT — Usually found in mountain woods. Prefers rich, moist, often rocky situations. Frequently occurs in shaded places under a dense canopy of larger trees. IMPORTANCE OF THE SPECIES- -This tree is of little forestal importance. It remains small, grows slowly and occurs scattered or in .--mall clumps. Its bright foliage and brilliant fruit recommend it for ornamental purposes. It reaches tree-size only in the South. 190 THE MAPLE FAMILY— ACERACEAE. The Maple family comprises in addition to the Asiatic genus Dip- teronia, with only 1 species, about 70 species, all of which are in- cluded in the genus Acer, and distributed with a few exceptions in the northern hemisphere. This family consists mainly of trees and a few shrubs. The members of this family are used more than those of any other family as ornamental and shade trees. Further charac- teristics of the family are included in the description of the sole American genus which follows. THE MAPLES— ACER, (Tourn.) L. This genus comprises approximately 70 species in the world, with 13 species in the United States and 6 species in Pennsylvania. A few exotic species have been introduced exclusively for ornamental and shade purposes. The commonest exotic species are the Norway Maple (Acer platanoides L.) and the Sycamore Maple (Acer Pseudo- platanus L.). On account of their abundance and wide distribution in this State, a descriptive page, together with an accompanying plate, has been devoted to these two species. The leaves of the Maples are opposite, usually simple or in a few species compound with 3-5 leaflets, and are shed in the autumn. The flowers are regular or polygamous, rarely perfect, and appear before, with or after the leaves. The time at which the flowers appear aids considerably in distinguishing the various species from each other. Some trees bear only staminate flowers, while others bear only pis- tillate, with the result that one may occasionally find a mature tree which does not produce any fruit. The flowers are pollinated by in- sects, which are attracted in hordes by the aromatic pollen-bearing blossoms. The fruit is composed of a pair of winged seeds joined to- gether to form the well-known maple key or samara, which matures in early or late summer, depending upon the species. The fruit which matures in early summer germinates at once, while that which matures in late summer remains dormant over winter and germinates the following spring. Wind is the chief agent which disseminates the seeds. The Maples are separated into two classes with reference to their commercial value, Hard Maple and Soft Maple. This classification is based upon the physical characteristics of the wood. The wood of the Maple is diffuse-porous with rather small medullary rays, usually fine-grained, dense, and in some species hard and beautifully curled and figured, which makes it especially prized for interior finish and cabinet work. Most species yield a saccharine sap which may be concentrated into maple syrup or maple sugar. Within a family one may often find a wide variation of plant or- gans, but the genus Acer possibly presents a wider range or a greater 191 variation in its organs than any other genus of trees found in this State. The leaves may be simple or compound, large or small, smooth or hairy. The twigs may be green, brown, or red. The flowers may be in small lateral clusters, in long terminal racemes, or in drooping clusters; appear before, with, or after the leaves. Their color may be green, yellow, or red. The fruit, while similar in all the species so far as type is concerned, varies considerably in size, divergence of the wing, and arrangement. Their habitat also varies, some like the Red Maple, preferring moist locations, while the Mountain Maple frequents rocky situations. In addition to these general differences among the species, a greater difference becomes evident as one studies the detailed description of the species which follow: SUMMER KEY TO THE SPECIES. Page. 1. Leaves simple, v 2 1. Leaves pinnately compound, A. Negundo 197 2. Leaf petioles with acrid milky sap, A. platanoidles 198 2. Leaf petioles without acrid milky sap 3 3. Flowers in terminal racemes, 4 3. Flowers in lateral clusters, appearing before or with the leaves 6 4. Flowers appear with the leaves A. Fseudo-platanus 198 4. Flowers appear after the leaves 5 5. Flowers in erect racemes; leaves coarsely serrate and usually 3-lobed,....A. spicatum 193 5. Flowers jn drooping racemes; leaves finely serrate, 3-lobed at apex, at first brown pubescent beneath, A. pennsylvanicum 192 6. Flowers opening before the leaves,, the drooping fruit ripening in spring or early summer v 7 6. Flowers opening with the leaves, drooping fruit ripening in summer or early autumn A. saccharum 194 7. Flowers with petals; leaves bright green above, pale green nearly glabrous beneath 3-5-lobed; fruit keys incurved, A. rubrum 196 7. Flowers without petals; leaves green above whitish or silvery beneath, deeply 5-lobed; fruit keys divergent A. saccharinum 195 WINTER KEY TO THE SPECIES. 1. Buds stalked with few exposed scales 2 1. Buds sessile or nearly so, with 6 or more exposed scales, 4 2. Buds evidently-stalked; bark streaked longitudinally with white lines, A. pennsylvanicum 192 2. Buds short-stalked; bark not streaked longitudinally with white lines, 3 3. Buds small, 1/5 of an Inch long including stalk; twigs reddish-brown to dingy gray; pith brown, A. spicatum 193 3. Buds large, ovoid, the terminal one acute the lateral obtuse and closely appressed; twigs greenish-purple and glaucous; pith light, '.A. Negundo 197 4. Buds with 8-16 exposed scales, brown, scute, non-collateral, leaf -scars nearly encircle stem A. saccharum 194 4. Buds with 6-8 exposed scales, red or green, obtuse, 5 5 Terminal buds small, generally less than 1/5 of an inch long; terminal and lateral buds of same size; collateral buds present, 6 5. Terminal buds large, generally over 1/5 of an inch long; terminal buds larger than lateral; collateral buds absent, 7 6. Twigs red and lustrous; bark rough but not flaking in large pieces, A. rubrum 196 6. Twigs bright chestnut-brown; bark falling away in thin large flakes, A. saccharinum 195 7. Buds red; leaf -scars encircle stem; lenticels scattered; lateral buds appressed; bark black, fissured, not scaly A. platanoides 198 7. Buds green; leaf -scars do not encircle stem; lenticels numerous; lateral buds pro- jecting; bark brownish and scaly A. Pseudo-platanus 198 192 STRIPED MAPLE. Acer pennsylvanicum, Linnaeus. FORM — Usually from 10-25 ft. in height with a diameter of about 6-12 inches, but may attain a height of 40 feet. Trunk usually short dividing into slender and straight branches which form a deep and broad crown. BARK — Thin, rather smooth, greenish or reddish-brown, conspicuously marked with longi- tudinal white streaks; later becomes rougher, darker, and less streaked. See Fig. 63. TWIGS — Smooth, stout, at first greenish, later red, with very few inconspicuous lenticels, and brown pith. Season's growth marked by 2 or sometimes 3 dark lines encircling the twig, formed by fallen outer bud- scales. White longitudinal streaks appear the second season. BUDS — Opposite, evidently-stalked, large, about 2/5 of an inch long excluding stalk, tapering but blunt-pointed, red, glossy, angular, covered by a single pair of red, smooth, val- vate scales enclosing a few pairs of smaller .and lighter scales. Outer scales are smooth on surface with ciliate margins while the inner scales are hairy as shown in opposite plate. Terminal buds are large while lateral buds are smaller and closely appressed. LEAVES — Opposite, simple, goose-foot-like, 3-lobed at apex, finely serrate on margin, rounded at base, rusty -pubescent below. Petioles long, grooved, with enlarged bases. LEAF-SCABS — Opposite, broadly U-shaped, nearly encircle stem; adjacent edges form rather blunt teeth which are separated by a ridge. Bundle-scars usually 3, often subdivided into 5-8. FLOWERS— Appear in May or June after the leaves are full grown in drooping terminal racemes. Staminate and pistillate flowers occur on same plant but in different clusters. FRUIT — Matures in September in drooping racemes; wings of the keys, thin, very divergent, about } of an inch long, marked on one side of seed with a depression. WOOD — Diffuse-porous; soft, close-grained, light brown with wide zone of sapwood. Seldom used commercially. Weighs 33.02 Ibs. per cubic foot. DISTINGUISHING CHARACTERISTICS — The Striped Maple, also known as Moosewood and Whistlewood, can be readily distinguished at all seasons of the year by the light longitudinal streaks on the branches and trunk. They often appear the second year and persist for many years on the trunk. In winter the large, evidently-stalked, valvate, and red buds together with the smooth branches and brown pith are characteristic. In summer the drooping raceme of flowers and the goose-foot-like leaves with their finely serrate margins and rusty pubescence on the lower surface are distinctive. RANGE — From Nova Scotia west to Minnesota, south especially along the mountains to Georgia. DISTRIBUTION IN PENNSYLVANIA— Rather common locally in the mountainous parts of the State especially on shaded slopes and in deep ravines. Very common in Mifflin, Centre, Blair, and Huntingdon counties. HABITAT — It prefers moist, cool, shaded, often rocky mountain slopes. IMPORTANCE OF THE SPECIES — The wood is of practically no commercial value. The chief value of the tree is its attractive ornamental qualities both as an individual tree and as a component of the understory of the forest structure. PLATE CIV. STRIPED MAPLE. 1. Branch with drooping raceme of staminate flowers, x i. 2. Branch with drooping raceme of pistillate flowers, x i. 3. Branch with mature leaves and drooping raceme of fruit, x 5. 4. A maple key with exposed seeds, x |. 5. Section of winter branch showing striped bark, buds, and leaf-scars, x 5. 6. Terminal section of winter twig showing evidently stalked buds with outer pair of bud scales separated, exposing the pubescent inner scales, natural size. 7. Section of winter twig showing opposite and stalked buds, and leaf-scars with bundle-scars, x 5. PLATE CV. MOUNTAIN MAPLE. 1. Branch with mature leaves and two erect racemes of flowers, x i. 2 Branch with a mature leaf and a raceme of fruit, x J. 3. A maple key with exposed seeds, x 1. 4. A seed, slightly enlarged. 5. Winter twig with stalked buds, lenticels and leaf-scars with bundle-scars, x J. 6. Section of a winter twig, enlarged. 193 MOUNTAIN MAPLE. Acer spicatum, Lambert. FORM — A shrub or small tree sometimes attaining height of 35 ft. with a diameter of 11 inches. Usually a shrub growing in clumps on rocky soil. Trunk usually short and bears rather straight, slender and upright branches. BARK — Thin, rather smooth, brown or grayish-brown mottled with dingy-gray blotches. TWIGS — Slightly hairy, at first reddish-puvple on exposed side and yellowish-green on shaded side, later bright red and then changing to grayish-brown, covered with few scattered lenticels; contain brown pith, and are encircled by 2 or 3 dark rings formed by the scars of fallen bud-scales. BUDS — Opposite, short-stalked, rather small, about 1 of an inch long including stalk; terminal bud larger and more acute-pointed than lateral appressed buds; one pair or sometimes t\v<> pairs of more or less hairy, grayish or greenish scales visible. LEAVES — Opposite, simple, 3-5-lobed, coarsely serrate on margin, cordate at base, some- what hairy on lower surface. Petioles long, slender, and enlarged at base. LEAF-SCARS — Opposite, V-shaped, hollow, with 3 bundle-scars, and nearly encircle stem. FLOWERS — Appear about June after the leaves are full grown, in erect terminal racemes. Staminate flowers occur usually at the top and the pistillate at the base of the raceme. FRUIT — Matures in September in drooping racemes; wings of the keys somewhat divergent, about £ of an inch long, the seed-bearing part strongly striated. WOOD — Diffuse-porous; soft, close-grained, light to reddish-brown with wide zone of light sapwood. Seldom used commercially. Weighs 33.22 Ibs. per cubic foot. DISTINGUISHING CHARACTERISTICS— The Mountain Maple is essentially a shrubby spe- cies growing in small clumps, and can be distinguished from most species of M;i] 1<- by its stalked, few-scaled winter buds, erect raceme of flowers, hairy -purplish ,to greenish twigs, and simple, 3-5 lobed coarsely serrate leaves. It differs from the closely related Striped Maple in the absence of light-striped bark and brown pubescence on the lower sides of the leaves, and in the presence of pubescence on the branches, and smaller often gaping l>uds. RANGE — Newfoundland to Manitoba, south to Michigan, Pennsylvania, and along the mountains to Georgia. DISTRIBUTION IN PENNSYLVANIA— Found locally in all parts of the State. Rather com- mon in the mountainous parts. HABITAT — It prefers moist rocky hillsides. Commonly found bordering ravines. It de- mands the shade of other species. Very thrifty on the moist slopes and tops of the southern Appalachian Mountains. IMPORTANCE OF THE SPECIES — It is of practically no commercial imi ortam-o as a timber tree, but is valuable as a soil protector on rock slopes where a protection forest is desirable. This species is planted very extensively for ornamental purposes. 13 194 SUGAR MAPLE. Acer saccharum, Marshall. FORM — A large timber tree attaining a maximum height of 120 ft. with a diameter of 5 feet. Open grown trees have short trunks bearing stout, rather erect branches which form a spreading, egg-shaped, often round-topped crown. Trees in closed stands have long, straight, clean trunks bearing shallow, round crowns with large limbs. BARK — On branches and young trunks .smooth and light brown; on older trunks brown, deeply channelled into long irregular plates or flakes which often loosen vertically along the side. See Fig. 62. TWIGS — Slender, smooth, reddish-brown to orange-brown, covered with numerous pale lenti- cels. BUDS — Opposite, brown, sharp-pointed, conical, hairy at apex; terminal bud about twice as long as appressed lateral ones; covered by overlapping scales, with from 8-16 of them exposed. LEAVES — Opposite, simple, usually 5-lobed, with a sparsely toothed margin and round- based sinuses, cordate at base, thin in texture, 8-5 inches long and greater in width. Mature leaves are bright green above and pale green beiow. LEAF-SCARS — Opposite, V-shaped to U-shaped, nearly encircling stem. Bundle-scars usually 3, in a lunate line. FLOWERS — Appear in April and May with the leaves, in drooping corymbs both from the terminal mixed buds and the lateral propagative buds. The staminate and pistillate occur in different clusters. FRUIT — Matures about September; clustered, borne on drooping stalks; wings of the keys about i-1 inch long, parallel, or slightly divergent. WOOD — Diffuse-porous; heavy, hard, olose-grained, with fine surface, light brown to reddish. Used for Interior finish, furniture, shoe lasts, railroad ties. Abnormal 'modifications of the structure of the wood known as Curly Maple and Bird's Eye Maple are rather common and especially prized in cabinet making. Weighs 43.0S Ibs. per cubic foot DISTINGUISHING CHARACTERISTICS — The Sugar Maple, also known as Hard Maple and Rock Maple, can be distinguished in summer from the other Maples by its large, simple leaves which are thin in texture and have their lobes coarsely toothed. The flowers appear with the leaves while those of the Red Maple and the Silver Maple appear before, and those of the Mountain Maple and the Striped Maple after the leaves. The fruit clusters of the Sugar Maple are usually developed from terminal buds while those of the Red Maple and Silver Maple are developed from lateral buds. The fruit of the Sugar Maple does not mature until September and may often persist into the winter while the fruit of the Red Maple and Silver Maple matures in early summer and germinates at once after falling upon the ground. In winter the Sugar Maple can be recognized by its conical, sharp-pointed, brown buds with from 8-16 exposed and overlapping scales, and by the slender brown twigs marked with pale lenticels. The rough furrowed trunk is also characteristic of older trees. ' RANGE — Newfoundland to Manitoba, south to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA— Common , especially in the northern and eastern parts of the State. It is possibly, next to Chestnut, the commonest tree in this State. HABITAT — It flourishes best on well drained rich soil, but will thrive even when the soil is not rich. It is common on low ridges at the base of mountains, and along slopes. It reaches its best development in central New England, New York, northern Pennsylvania, and the Lake States. IMPORTANCE OF THE SPECIES— The Sugar Maple is a valuable timber tree. Its im- portance is being realized more as its wood finds new uses. The process of timber impregna- tion has raised the value of the wood of this species. It is not only valuable as a timber tree but produces annually .n large quantity of maple sugar and maple syrup, and in addition is one of our most attractive ornamental trees. PLATE CVI. SUGAR MAPLE. 1. Branch with immature leaves and staminate blossoms, x J. 2. Staminate flower with calyx, enlarged. 3. Longitudinal section of staminate flower, en- larged. 4. Branch with immature leaves and pistillate blossoms, x J. 5. Pistillate flower with calyx, enlarged. 6. Longitudinal section of flower with both a pistil and stamens, enlarged. 7. Branch with mature leaves and cluster of fruit, x 5. 8. A maple key with exposed seeds, x J. 9. Winter twig showing lenticels, leaf -scars, bud-scale scars, and sharp-pointed opposite buds, x }. PLATE CVII. SILVER MAPLE. 1. Flowering branch, x J. 2. Branch with mature leaves and mature fruit, z ft. 3. A wing of a maple key with exposed seed, * a. 4. A seed, enlarged. 5. End view of a seed, enlarged. 6. A winter twig showing buds, lenticels, leaf- scars, bud-scale scars and bundle-scars, x J. 195 SILVER MAPLE. Acer saccharinum, Linnaeus. FORM — Usually a tree about 50-60 ft. in height but may attain a maximum height of 120 ft. with a diameter of 45 feet. Trunk short and divides into lateral branches which again freely subdivide ami form a broad head. Lateral branches have pronounced droop, and distinct upward curve at the end. BARK — On branches and young trunks smooth and gray; on old trunks brown with a some what furrowed surface separating into thin flakes which are fastened at the center and loose at both ends. TWIGS — Somewhat slender, glossy, at first green, later bright chestnut-brown, covered with numerous light lenticels-. BUDS — Opposite, red, obtuse-pointed, sessile or short-stalked; flower buds stout, spherical, accessory, covered with overlapping scales, 6-3 of which may be exposed. Margin of scales ciliated and often light in color. LEAVES — Opposite, simple, 5-lobed, coarsc;ly toothed; bright green on upper surface and silvery -white on lower; with deep round-based sinuses. LEAF-SCARS — Opposite, U-shaped to V-shaped, not encircling stem. Bundle-scars 3, in a lunate line. FLOWERS — Appear in March or April before the leaves are out, in dense, sessile, axillary clusters. Starninate and pistillate occur in separate clusters sometimes on the same, some- times on different trees. Petals absent. FRUIT — Matures about May; clustered along branchlets, borne on slender drooping stalks; wings of the keys usually from 1-2 inches lung, divergent, sometimes straight, or curved. WOOD — Diffuse-porous; moderately hard, rather brittle, close-grained, with wide sapwood. Used for flooring, cheap furniture, and paper pulp. Weighs 32.84 Ibs. per cubic foot. DISTINGUISHING CHARACTERISTICS— The Silver Maple, also known as White Maple, River Maple, and Soft Maple, can be recognized in summer by its leaves with a silvery-white lower surface and deep round-based sinuses, in winter it closely resembles the Red Maple but may bo distinguished from it by the pungent odor of the broken twigs and the bright chestnut-brown twigs. The bark of the Silver Maple is somewhat furrowed and separates into thin flakes which are loose at both ends and fastened in the middle. The lateral branches have a pronounced droop and a distinct upward curve at the ends. This may sometimes be a dis- tinctive character. The Red Maple and the Silver Maple are distinguished from all the other Maples of the State by the numerous, round, red, collateral buds. RANGE — New Brunswick to southern Ontario, south to Florida and Indian Territory. DISTRIBUTION IN PENNSYLVANIA— Occasional and local throughout the State, especially along larger streams. HABITAT — It prefers a moist deep soil such as is found along stream banks. It will exist in drier locations but not attain a large size IMPORTANCE OF THE SPECIES — The Silver Maple is a very attractive ornamental tree. A few special ornamental varieties have been developed. The wood is brittle and consequently the branches are apt to be broken off during a storm. This defect somewhat checks the planting of this species in exposed places. It is a rapid grower. The wood which it produces is of no special commercial importance and consequently it has little to recommend it for forestry purposes, except that it forms an excellent soil covor in the under-story of the forest. 196 RED MAPLE. Acer rubrum, Linnaeus. FORM — Usually a tree about 50 ft. high, but in a moist habitat sometimes attains a height of over 100 ft. with a diameter of 4 feet. When grown in the open it branches near the ground and forms a deep, broad, dense crown. Upper lateral branches are rather upright while lower ones are horizontal and slightly turned upwards at the end. BARK — On branches and young trunks smooth and gray; on old trunks dark grayish, thick, shaggy, and roughened by long ridges which peel off in long plates. See Figs. («) and (51. TWIGS — Somewhat slender, glossy, at first green, later red, covered with numerous light lenticels. BUDS — Similar to those of the Silver Maple. See page 195. LEAVES — Opposite, simple, 3-5-lobed, coarsely-toothed, light green above, pale green to whitish below, with rather shallow sharp-based sinuses. LEAF-SCARS — Opposite, U-shaped to V-shaped, not encircling stem. Bundle-scars 3, in a lunate line. FLOWERS — Appear In March or April before the leaves are out, in dense sessile axillary clusters. Staminate and pistillate occur in different clusters, on the same or different trees. Petals present. FRUIT — Matures in May or June; clustered and borne on drooping stems; wings of the keys usually less than 1 inch long, red to brown in color, at first convergent but later divergent. WOOD — Diffuse-porous; rather soft, not strong, close-grained, light brown with wide light sapwood. Used for furniture, in turnery, and paper pulp. Weighs 38.5 Ibs. per cubic foot. DISTINGUISHING CHARACTERISTICS— The Red Maple, also known as Soft Maple, Swamp Maple, and White Maple, can be recognized in summer by its simple, rather small, 3-5-lobed, coarsely-toothed leaves which are rarely silvery-white underneath, and have rather shallow sharp-based sinuses. In winter it closely resembles the Silver Maple, but may be distinguished by its red lustrous twigs and the absence of a pungent odor, from broken twigs. In winter these two closely related species can be distinguished from the Sugar Maple by their numerous, round, red, collateral buds; from the Striped Marie and the Mountain Maple by their larger size and the absence of stalked buds; from the Ash-leaved Maple by the absence of short-stalked downy buds and greenish twig covered with a whitish bloom. The European species, both Norway Maple and Sycamore Maple, have much larger buds and stouter twigs. RANGE — Nova Scotia to Manitoba, south to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA— Common locally throughout the State, especially in regions traversed by streams and in wet habitats. HABITAT — It prefers wet soil, often found in swamps but also frequents drier hillsides. Commonly found along rivers, creeks, lakes, in swamps, and as an' undergrowth in the forest over extensive, and often rather hilly areas. IMPORTANCE OF THE SPECIES— The Red Maple produces a wood which at present is of little commercial importance It may in time become more valuable. The despised species of to-day may be the prized species of to-morrow. It is tolerant of shade and its chief future value in forestry may be in furnishing soil protection as a member of the under-story of the forest. It may play the same role in our future forest that Beech is playing to-day in the intensively managed forests of Germany, only that it is of less value for fuel. PLATE CVIII. RED MAPLE. 1. Flowering branch, x 1. 2. Branch with mature leaves and mature fruit, x J. 3. A maple key with exposed seeds, x $. 4. A winter branch, x J. 5. Section of winter twig showing lenticels, a leaf-scar and a gaping lateral bud, natural size. 6. Section of twig showing conspicuous lenticels and a cluster of accessory buds, natural size. 4 PLATE CIX. ASH-LEAVED MAPLE, or BOX ELDER. 1. Branch with immature leaves and staminate blossoms, x J. 2. A drooping raceme of pistillate blossoms, x J. 3. Branch with mature leaves and a raceme of mature fruit, x J. 4. A key of fruit with exposed seeds, x i. 5. A winter twig, x J. 6. Section of a winter twig showing a gaping bud and a leaf-scar with bundle-scars, enlarged. 7. Diagramatic section of a twig with buds and a covering leaf-base, enlarged. 197 ASH-LEAVED MAPLE, or BOX ELDER. Acer Negundo, Linnaeus. FORM — A medium-sized tree occasionally attaining a height of 70 ft. with a diameter of 3 feet. Trunk usually short, dividing into stout, sometimes drooping branches which form a deep broad crown. Occasionally an open grown tree possesses a long clean trunk. BARK — Or. branches and young trunks smooth and grayish-brown; that of older ones rather thick, distinctly narrow ridged, and seldom scaly. TWIGS — Stout, purplish-green or green, sometimes smooth, often covered with a whitish bloom and scattered raised lenticels. BUDS — Opposite, short-stalked, large, ovoid; the terminal acute and the lateral obtuse; white-woolly, covered by bucL-scales, the outer pair usually completely enclosing the inner pair. Collateral buds are common and often distend outer scales. LEAVES — Opposite, compound, with 3-5 leaflets. Leaflets ovate, coarsely and irregularly serrate, 2-4 inches long and 2-3 inches broaci. LEAF-SCARS — Opposite, V-shaped, bordered by light colored margin, encircling stem so that adjacent edges of opposite scars meet at a very sharp angle. Bundle-scars usually 3, seldom divided, arranged in a lunate line. FLOWERS — Appear in April before or with the leaves on the past season's growth. Stami- nate and pistillate occur on different trees, the former on hairy drooping pedicels, the latter in narrow drooping racemes. FRUIT — Matures about September but is full grown earlier. Wings of the keys about H-2 inches long, parallel or incurved, borne in drooping racemes. Fruit-stalks persist far into winter. WOOD — Diffuse-porous; light, soft, creamy- white, close-grained, not durable. Used in the manufacture of woodemvare, cooperage, wood pulp, and sometimes in cheap furniture. Weighs 26.97 Ibs. per cubic foot. DISTINGUISHING CHARACTERISTICS— The Ash-leaved Maple, also known as Box Elder, is readily distinguished in summer by its opposite, compound leaves with 3 to 5 leaflets and its green branchlets covered with a whitish bloom. The maple keys arranged in drooping racemes are also characteristic. In winter the green branchlets are distinctive together with the large, ovoid, often collateral and downy buds. The leaf -scars encircle the stem and their adjacent edges form a very sharp angle. RANGE — Vermont westward to Ontario, south to Florida, Texas, and Mexico. DISTRIBUTION IN PENNSYLVANIA— Rare r.nd local. Most abundant in the eastern and southern parts of the State with a few outposts reported in Westmoreland and Allegheny counties. HABITAT — Thrives best in moist soil, but also tolerant of drier situations. Commonly found along streams, border of laker, or swamps. Often planted for ornamental purposes on dry locations. IMPORTANCE OF THE SPECIES — It is of little commercial importance as a timber tree. It yields a sap from which some maple sugar is made locally. This tree is very attractive as an ornamental tree and is planted extensively as a shade, lawn, road-side and park tree. It grows rapidly and has an attractive form in winter and a dense green foliage in summer, 198 SYCAMORE MAPLE. Acer Pseudo-platanus, Linnaeus. The Sycamore Maple is a European species. It is native to central Europe where it attains a height of 120 ft. and develops a large spreading head. The trunk is sometimes furrowed and the bark flakes off in thin scales. This tree is considered the most attractive of the Maples for ornamental planting. It is rather intolerant of soil conditions and consequently not planted so extensively as the Norway Maple. The Sycamore Maple is readily distinguished by its firm, 3-5-lobed leaves with sharply serrate margins, acute-based sinuses, and pubescent lower leaf-surfaces. In winter the large, obtuse, green buds are characteristic together with the leaf -scars which do not quite encircle the stem. The lenticels are also more numerous and the lateral buds stand out from the twig more than on the Norway Maple. The fruit keys are also smaller and the wings less divergent than those of the Norway Maple. NORWAY MAPLE. Acer platanoides, Linnaeus. The Norway Maple is a European species extending from Norway to Switzerland. It attains a height of 100 ft. and develops a round head. The trunk of the tree is closely fissured but not scaly. This tree is one of our most attractive ornamental trees and is planted extensively along the streets in cities and in lawns and parks. It is especially adapted for city planting because it is more tolerant of unfavorable city conditions than our native Maples. It is also rather free from the attacks of insects and fungi, and retains the leaves longer in fall than our native species. The wood is of no commercial importance in America, but is used for minor purposes in Europe. The Norway Maple can readily be distinguished in summer by its large leaves which resemble those of our Sugar Maple, but are deeper in color and firmer in texture. The large- toothed and almost entire-margined leaves are readily recognized from the smaller 3-5-lobed leaves of the Sycamore Maple with sharply serrate leaf-margins. A certain test for identifying the Norway Maple is the presence of milky sap in the leaf-petiole which readily exudes upon twisting. In winter the Norway Maple can be recognized by the large, obtuse, glossy, red buds which may be more or less olive-green at the base and by the lateral closely appressed buds. The leaf-scars which encircle the stem are also characteristic. The very divergent wings of the large maple keys and the closely fissured, but not scaly bark will also aid In recog- ing it. PLATE CX. EUROPEAN MAPLES. SYCAMORE MAPLE. NORWAY MAPLE. 1. A spike of flowers, x J. 2. Branch with leaves and fruit, x 1. 3. A key of fruit, x J. 4. A seed, natural size. 5. A seedling, x |. 6. A winter twig, x J. 7. A leaf-scar, enlarged. 8. A cluster of flowers, x J. 9. Branch with leaves and fruit, x 4. 10. A key of fruit, x \. 11. A seed, natural size. 12. A seedling, x \. 13. A winter twig, x J. H. A leaf -scar, enlarged. PLATE CXI. HERCULES' CLUB. 1. Section of a branch with compound leaves, x 1. 2. A panicle of flowes, x J. 3. A panicle of fuit, x J. 4. A winter twig, x 5. 5. Section of a winter twig, natural size. 199 HERCULES' CLUB. Aralia spinosa, Linnaeus. FAMILY AND GENUS DESCRIPTION— This species belongs to the Ginseng family, Aralia - ceae, which comprises about 52 genera with 4f>0 species of herbs, vines, shrubs, or trees. The members are widely distributed but commonest in the tropics. The English Ivy (Hede^ra Helix L.) an evergreen climber is one of its most common representatives. The Common Ginseng (Panax quinquefolium), is a well-known member of this family. The flora of Pennsylvania comprises 2 genera with G species. The species described here is the only tree representative in North America. The genus Aralia to which it belongs comprises about 30 species, mostly herbs, native to North America and Asia. FORM — It may attain a height of 40 ft. with a diameter of 12 inches, but usually 10-20 ft. in height with a diameter of 4-8 inches. Trunk may be branchless or sometimes covered with stout widespreading branched. BARK — Thin, brown outside, yellow inside, at first smooth, later divided into rounded broken ridges. TWIGS — Very stout, i-§ of an inch in diameter, armed with stout, scattered prickles, roughened by long narrow leaf-scars which nearly encircle the twig. BUDS — Alternate; terminal bud present, about £-2 of an inch long, chestnut-brown, conical, blunt-pointed. Lateral buds 1 of an inch long, flattened, often triangular. LEAVES — Alternate, compound or doubly compound, often 3 ft. long and 2-2| ft. wide. Leaflets ovate, 2-3 inches long, thick, wedge-shaped or rounded at base, sharp-pointed at apex, serrate on margin, sometimes a little hairy on lower surface. Enlarged bases of the leaf-petioles sheath the twigs. LEAF-SCARS — Alternate, narrow, long, about half encircle the twig, taper to a point, embrace lateral buds, stand in a horizontal position, i. e. their plane is often at right angles to the main axis of the twig. Each leaf -scar conlains about 12 bundle-scars arranged in a curved line. FLOWERS — Appear from June to August. Each flower is usually perfect and cream white. Many of them are grouped together in paaicled-umbels which occur solitary or in groups often 3-4 ft. long. FRUIT — An ovoid black berry about \ of an inch long, 5-angled, and terminated with blackened persistent styles. WOOD — Soft, brittle, weak, close-grained, brown with yellow streaks; sapwood narrow. DISTINGUISHING CHARACTERISTICS — The Hercules' Club, also known as Angelica Tree, can be distinguished by its large leaves which may be once, twice, or thrice compound. The leaves are the largest of our native trees. They may be 3-4 ft. long and 2-2i ft. wide. The petioles have enlarged clasping bases. The terminal buds are conical and J-l of an inch long and the lateral ones are triangular and 1 of an inch long. The elongated narrow leaf-scars half encircle the twigs. The stout twigs and the petioles are armed. The small white flowers are arranged in panicled-umbols often over 2 ft. long. Its habit of growth is unique in that a number of unbranched but armed stems come up in rather dense clumps. RANGE — Southern New York to Florida, west to Missouri and Texas. DISTRIBUTION IN PENNSYLVANIA— Found locally throughout the southern half of the State. Not reported from the northern or northeastern parts. Local outposts of it are reported from the northwestern part. HABITAT — Prefers rich moist bottomland. Common in moist and fertile woodlands. IMPORTANCE OF THE SPECIES— This species is of no commercial value. It remains small, produces inferior wood, and is local and limited in its distribution. The tree grows rapidly and is planted rather extensively for ornament. 200 FETID BUCKEYE. Aesculus glabra, Willdenow. FAMILY AND GENUS DESCRIPTION — The Soapberry family, Sapindaceae, comprises about 100 genera with more than 1,000 species. They are widely distributed, but commonest in the tropical regions of the Old World. The flora of North America comprises 6 genera of trees with about 13 species. The genus Aesculus alone has representatives in Pennsylvania. It comprises 14 species, 10 of which are native to America and 2 to Pennsylvania. In addition to the native species, the Horse-chestnut ( Aesculus Hippocastanum) is widely introduced in this State. FORM — Usually a email tree not over 40 ft. in height with a diameter of 12 inches, but may reach a height of 90 ft. with a diameter of 24 inches. Trunk short and slender. Crown broad, deep, round-topped. BARK — Gray, thick, evidently-furrowed, breaking up into plates. TWIGS — Stout, at first downy and brown, later smooth, reddish-brown to ashy-gray; ill- smelling if bruised. Pith large, light green, circular in outline. BUDS — Opposite; terminal buds normally present but occasionally absent; about $ of an inch long, sharp-pointed, resinous, covered by nearly triangular keeled scales. Outer bud- scales reddish-biown, finely hairy on margin, covered with a thin bloom; inner bud-scales yellowish-green, enlarging in spring to 1-2 inches and persisting until leaves are half developed. LEAVES — Opposite, compound with 5, farely 7, leaflets. Leaflets ovate to oval, 3-6 inches long, rather long-pointed at apex, narrowed at base, irregularly and finely toothed on margin; when young rather hairy, later smooth, yellowish-green above, paler beneath. Leaf-stalks 4-6 inches long, stout, hairy when young, enlarged at base. Foliage ill-smelling if bruised. LEAF-SCARS — Opposite, large, heart-shaped to inversely triangular. Bundle-scars large, in more than 3s, usually S-H, often arranged in 3 groups. FLOWERS — Appear about April or May after the leaves are developed. Small, yellowish or greenish, with four upright petals; borne in more or less downy terminal panicles about 5-6 inches long and 2-3 inches broad. Pedicels 4-6-flowered. Stamens project beyond yellow corolla. FRUIT — Matures about October. A thick, round or pear-shaped, prickly capsule about 1 inch in diameter, borne on stout stalks, containing a single large, smooth, lustrous somewhat flattened brown nut. The falling fruit leaves a large scar on the twigs. WOOD — Diffuse-porous; rays very fine, indistinct; pores very small, invisible to unaided eye, evenly distributed, mostly solitary; wood elements not in tier-like arrangement. Wood is weak, soft, whitish or sometimes pale yellow, lustrous. Weighs 28.31 Ibs. per cubic foot. Used for paper-pulp, woodeuware, artificial limbs, chip hats. DISTINGUISHING CHARACTERISTICS— The Fetid Buckeye, also known as Ohio Buckeye, Stinking Buckeye, and American Horse-chestnut, can be distinguished by its leathery, dehiscent fruit containing one to three shining seeds. The fruit of .this species is covered with spines. while that of the Sweet Buckeye is smooth. The leaves are opposite and digitately com- pound with usually 5 or occasionally 7 leaflets. The buds are free from a resinous coating; the terminal one is often lacking. The flowers are showy, yellowish or greenish in color and arranged in large panicles borne at the ends of branches. The stamens project beyond the corolla while those of the Sweet Buckeye are just as long or shorter than the corolla. It is native only in the western part of the State. RANGE — Western Pennsylvania, south to Alabama, west to Illinois, Iowa, and Oklahoma. DISTRIBUTION IN PENNSYLVANIA — Found only in the extreme western part of the State. Reported from Allegheny, Fayette, Lawrence, Mercer, and Westmoreland counties. HABITAT — Usually found growing in moist soil. Prefers banks of streams, ravines, or simi- lar situations. IMPORTANCE OF THE SPECIES — This tree is of no commercial importance in Pennsylvania. It is very limited in its distribution and usually remains small. It is occasionally planted as an ornamental tree, but is less popular than the Horse-chestnut. PLATE CXII. FETID BUCKEYE. 1. A flowering branch, x J. 2. A flower with stigma below anthers, natural size. 3. A flower with stigma above anthers, natural size. 4. A fruiting branch, x J. 5 A fruit with part of shell removed showing two seeds, x 4 6. A seed, x J. 7. Longitudinal section of a seed, x I. 8. A winter twig, x *. 9 Section of a winter twig showing a leaf-scar with bundle-scars, natural si/*-- PLATE CXIII. SWEET BUCKEYE. 1. A flowering branch, x J. 2. A tlower with stigma below anthers, natural size. 3. A flower with stigma above anthers, natural size. 4. A fruiting branch, x J. 5. A seed, x J. 6. Longitudinal section of a seed, x j. 7. A winter twig, x i. 8. Section of a winter twig showing a leaf-scar with bundle-scars, slightly enlarged. 201 SWEET BUCKEYE. Aesculus octandra, Marshall. FORM — The largest American species of the genus. Usually a small tree less than 60 ft. in height with a diameter of 18 inches, but may reach a height of 110 ft. with a diameter of over 3 feet. At its optimum in western North Carolina and eastern Tennessee. Reported a mere shrub in western Texas. BARK — Light brown to grayish-brown, evidently-fissured, breaking up into manjy thin irregular scales. See Fig. 58. TWIGS — Stout, at first finely hairy, becoming smooth, reddish-brown to ashy-gray, slightly ill-smelling when bruised. Pith large, light green, circular in outline. BUDS — Opposite; terminal bud present and about 4/5-2 inches long; non-resinous, somewhat blunt-pointed, covered by nearly triangular or ovate keeled scales. Outer bud-scales reddish- brown, covered with a thin bluish bloom; inner bud-scales yellowish-green, enlarging in spring to 1-2 inches. LEAVES — Opposite, compound, with 5, sometimes 7, short-stalked or stalkless leaflets. Leaflets oval to obovate, 4-10 inches long, finely toothed on margin, long-pointed at apex, narrowed at base, dark green and smooth on upper surface when mature, yellowish-green and -somewhat hairy on under surface. LEAF-SCARS — Opposite, large, heart-shaped to inversely-triangular. Bundle-scars large, in more than 3s, usually 3-9, often arranged in 3 groups. FLOWERS — Appear about April or May when the leaves are developed. Small, yellow or purplish, with 4 conniving petals; borne in finely hairy terminal panicles about 4-12 inches long. Stamens are included in yellow corolla. FRUIT — Matures about October. A smooth obovoid capsule, about 1-2 inches thick. Seeds several, large, smooth, reddi&h-brown, lustrous, 3-li inches broad, somewhat flattened. Valves of capsule thin, pale brown, not spiny or warty. The fruit is poisonous to stock, but seldom proves fatal. WOOD — Similar to that of the Fetid Buckeye, page 200, but it is somewhat lighter in weight and has the wood elements in a tier-like arrangement. Used for lumber, veneer, slack cooperage, paper-pulp, candy boxes, dishes, bowls, and artificial limbs. < DISTINGUISHING CHARACTERISTICS— The Sweet Buckeye, also known as Yellow Buck- eye and Big Buckeye, is native only to the extreme western part of the State. The leaves are opposite, digitately compound with usually 5 or sometimes 7 leaflets. The flowers are showy, yellowish in color, an3 arranged in large panicles borne at the ends of branches. The stamens are usually included in the corolla" while those of the Fetid Buckeye project beyond it. The valves of the fruit-capsule are smooth. The twigs are stout, contain a large pith and are roughened by largo conspicuous bundle-scars. The buds are large and non-resinous. The twigs when bruised are less ill-smelling than those of the Fetid Buckeye. It is the largest American species of the genus. RANGE — Western Pennsylvania to Illinois, Iowa, and Oklahoma, south to Georgia and Texas. DISTRIBUTION IN PENNSYLVANIA— Found only in the extreme western part of the State. Reported from Allegheny county. HABITAT — Usually grows in mixture with hardwoods in rich soil. Prefers rich bottom- lands and valleys. Common along or near streams. IMPORTANCE OF THE SPECIES — This tree is of no commercial importance in Pennsylvania. It is very limited in its distribution in the State. The wood which it produces and the small size which it attains in the northern pa it of its range do not Justify its planting for forestry purposes. It is, however, the largest American representative of the genus. It grows rapidly and may be planted for ornamental purposes. 202 BASSWOOD. Tilia americana, Linnaeus. FAMILY AND GENUS DESCRIPTION— The Linden family, Tiliaceae, comprises about 35 genera with probably 375 species found in temperate and tropical regions. The members consist of trees, shrubs, and a few herbs. One genus, Tilia, alone has tree representatives in North America. This genus comprises about 20 species, 8 of which are native to North America and 3 to Pennsylvania. Two species are described here. The third species, known as Michaux's Basswood (Tilia Michauxii Nutt.) is very rare in this State. Its leaves which are densely pubescent and grayish-green beneath and its floral bracts usually rounded at the base are distinctive. The bark of the branches is usually smoother and lighter than that of the 2 other native species. FORM — A large tree usually attaining a height of 60-70 ft. but may reach a height of 120 ft. with a diameter of 4J feet. Trunk straight, clean, with little taper. Crown dense, broad, rather deep, ovoid or rounded. BARK — On old trunks firm but easily cut, thick, longitudinally-furrowed into flat scaly ridges. Ridges often divided by transverse recendary furrows. On young stems dark gray and smooth. See Fig. 79. TWIGS — Smooth or very finely hairy, shining, bright red; second year olive, olive-red, or covered with a gray skin; usually zigzag, tough, mucilaginous if chewed, covered with scattered, dark, oblong lenticels. In cross-'jection, characteristic blunt conical masses with intervening lighter colored areas are present. BUDS— Alternate; terminal bud absent; ovoid, 2-ranked, stout, often somewhat flattened, divergent, usually deep red, occasionally greenish, mucilaginous, smooth or sometimes slightly hairy towards apex. Bud -scales glabrous, thick, rounded at back, usually 3 visible; one large scale makes bud unsymmetrical. LEAVES — Alternate, simple, ovate to orbicular, 4-7 inches long, firm in texture, long- pointed at apex, deeply toothed on margin with sharp teeth, unequally heart-shaped to truncate at base, dark green and shining on upper surface, green and smooth on lower except for a few rusty hairs. Leaf-stalks slender, $ length of blade. The side of the leaf nearest the branch is the largest. LEAF-SCARS — Alternate, large, conspicuous, raised, 2-ranked, containing few to many bundle-scars arranged in a ring or a single curved line, or scattered. Stipule-scars distinct, one narrow, the other broad; often show bundle-scars. FLOWERS — Appear about June. Perfect, regular, sweet, fragrant, yellowish-white, 5-20 in drooping cymose clusters. The long peduncle which bears the flowers is united for about half its length with a conspicuous green bract. FRUIT — A wooty, spherical, nut-like drupe about the size of a pea. Occurs singly or in small clusters with a common stalk attached to a leafy bract and often persisting far into winter. WOOD — Diffuse-porous; rays distinct, but colorless; light, soft, compact, moderately strong, light brown to nearly white, fine in texture; little difference between spring wood and summer wood. Weighs 28.20 Ibs. per cubic foot. Used in the manufacture of paper-pulp, wooden- ware, cheap furniture, panels for carriages, kegs, pails, barrel headings, berry boxes. DISTINGUISHING CHARACTERISTICS — The Basswood, also known as Linden, Lime-tree, Whitewood, Beetree, Whistle-wood, and Lynn, may be distinguished by its large, firm un- equally based leaves with green and smooth lower surfaces, by its smooth bright red twigs, by its alternate, deep red, unsymmetrical buds with 2-3 visible scales, by its white flowers arranged in drooping clusters attached to a green bract, and by its woody spherical nut-like drupe about the size of a pea attached to winged bracts. The dark funnel-shaped areas in the inner bark alternating with lighter areas as seen in a cross-section of a twig are characteristic. The smooth dark gray bark of younger stems and the thick longitudinally-furrowed bark on older trunks are distinguishing features. RANGE — New Brunswick to Manitoba, southward to Georgia and eastern Texas. DISTRIBUTION IN PENNSYLVANIA — Common in the eastern and southeastern parts of the State. Rare in the mountainous parts except in rich valleys. Locally abundant in the western part. HABITAT — Rarely grows in pure stands, but usually mixed with other hardwoods. Prefers rich soils in bottomlands. It can endure considerable shade. It suffers little from windfall but occasionally from windbreak upon exposed situations. IMPORTANCE OF THE SPECIES — This tree is one of our important timber trees on ac- count of the valuable wood and the bark which it produces. Seeds or seedlings may be planted. If seedlings are used, they should be planted early in spring before growth starts. The tree sprouts from stump very freely (Fig. 79). It grows rapidly, produces beautiful sweet smelling flowers, and is rarely attacked by fungi. It is one of our most attractive ornamental trees. PLATE CXIV. BASSWOOD. 1. A flowering branch with mature leaves, x 5. 2. Longitudinal section of a flower, slightly en- larged. 3. A fruiting branch, x 1. 4. A winter twig, x 1. 5. Section of a winter twig, enlarged. 6. A leaf-scar with bundle-scars, enlarged. PLATE CXV. WHITE BASSWOOD. 1. A flowering branch with mature leaves, x J. 2. Longitudinal section of a flower, slightly enlarged. 3. A fruiting branch, x 5. 4. A winter twig, x J. 5. Section of a winter twig, enlarged. 203 WHITE BASSWOOD. Tilia heterophylla, Ventenat. FORM — Usually 50-60 ft. high but may reach u height of 90 ft. with a diameter of 4i feet. It becomes as thick but not so high as the Basswood. Trunk straight, clean, slightly tapering. Crown dense, broad, rather rounded. BARK — Similar to that of the Basswood, page 202. TWIGS — Similar to those of the Basswood, page 202. BUDS — Similar to those of the Basswood, page 202. LEAVES — Alternate, simple, variable in outline, oblong-ovate to orbicular-ovate, 5-8 inches long, firm in texture, short taper-pointed at apex, deeply toothed on margin with sharp teeth, unequally heart-shapod to truncate at base; upper surface dark green and smooth, lower surface silvery-white and finely hairy. Leaf-stalk slender, J length of blade. The side of the leaf nearest the branch is the largest. LEAF-SCARS — Similar to those of the Basswood, page 202. FLOWERS — Appear about June or July. Perfect, regular, sweet, fragrant, yellowish -white, 5-15 in drooping cyruose clusters. The long peduncle which bears the flowers is united for about half its length with a conspicuous green bract. FRUIT — A woody, spherical, nut-like drupe about the size of a pea. Occurs singly or in small clusters with a common stalk attached to a leafy bract and often persists far into winter. WOOD — Similar to that of the Basswood, page 202, only about 2 pounds lighter. DISTINGUISHING CHARACTERISTICS— The White Basswood, also known as White Linden, has the general characteristics of the Basswoud, page 202. It can be distinguished from the latter by its leaves which are slightly larger, silvery-white and finely hairy on the lower surface, while those of the Basswood are green and smooth. The Basswood also roaches a somewhat larger size and has a wider distribution in this State than the White Basswood. RANGE — New York to Florida, westward to Illinois, Tennessee, and Alabama. DISTRIBUTION IN PENNSYLVANIA — Locally in the northeastern, eastern, and southern parts. Sparse in the mountainous parts. Not known to occur in the western part. HABITAT — Usually found in rich woods in mountainous regions. Tolerates dense shade, but thrives in full light. Occurs in mixture with other hardwoods. Common on limestone soil. IMPORTANCE OF THE SPECIES — This tree is of little commercial importance in this State on account of its limited distribution. Farther south it is more abundant, being the prevail- ing Basswood of West Virginia. It is one of our most attractive ornamental trees. 204 FLOWERING DOGWOOD. Cornus florida, Linnaeus. FAMILY AND GENUS DESCRIPTION — The Dogwood family, Cornaceae, comprises about 15 genera found mostly in temperate regions. Only 2 genera are native to North America, both of which have representatives in this State. They are the Dogwoods, Cornus, and the/ Gums, Nyssa. The genus Cornus is widely distributed in temperate regions and comprises about 40 species of which number 15 are native to North America and 8 to Pennsylvania. A few species reach tree-size and yield a very hard and valuable wood. FORM — A small tree usually from 15-25 ft. high but may reach a height of 40 feet with a diameter of 18 inches. Trunk with little taper up to the first branches and then practically disappears entirely in the branches. Crown low, broad, high, and rather dense. BARK — On younger stems and branches light brown to reddish-gray and rather smooth. On older stems reddish-brown to black, broken up into quadrangular scaly blocks. Bark rather bitter and ill-smelling. See Fig. 103. TWIGS — Usually red, sometimes tinged with green, smooth, glossy, often covered with a glaucous bloom; lenticels few and small; pith white and gritty. BUDS — Opposite; terminal bud present. Flower-buds terminal, spherical, 1/5-2/5 of an inch broad, covered by two opposite pairs of bud-scales. Lateral buds small often covered by persist- ent bases of leaf -stalks. Terminal leaf -buds reddish, slightly downy, covered by 2 gaping;' bud-scales. « LEAVES — Opposite, simple, clustered towards end of branches, ovate, 3-5 inches long, 2-3 inches wide, acute at apex, wedge-shaped at base, entire to wavy on margin, bright dark green above, "pale below. Midrib and primary veins prominent.* LEAF-SCARS — Opposite, may or may not encircle stem; bundle-scars 3 and occasionally more. Evidently-raised on the base of leaf-stalks on season's growth, and forming a deep V- shaped notch between them. FLOWERS — Appear about April. Perfect, greenish, arranged in dense heads, and surrounded by a large white involucre which is often aiistaken for the corolla. FRUIT — Ripens about October. A scarlet ovoid drupe about 3/5 of an inch long, containing a grooved stone, borne solitary or in clusters of 2-5 on a stalk. Undeveloped pistillate flowers often persist about base of fruit. WOOD — Diffuse-porous; medullary rays distinct; light red or pink in color. Wood very heavy, hard, strong, tough, pale reddish-brown to pinkish, with lighter colored sapwood. Weighs 50.81 Ibs. per cubic foot. Used for shuttles, golf stick heads, brush blocks, wedges, engraver's blocks, tool handles, and many kinds of turnery. DISTINGUISHING CHARACTERISTICS— Ihe Flowering Dogwood, also known as Boxwood, Dog- wood and Flowering Cornel, can be distinguished by its opposite branching, bright red or occa- sionally greenish twigs, small lateral buds covered by the persistent bases of the leaf-stalks, large spherical1 flower-buds, terminal leaf -buds with a single pair of bud-scales, and by its alligator bark. In autumn the fruit, and in spring the flowers, also aid in distinguishing it. RANGE — Massachusetts west through Ontario to Michigan and Missouri and south to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA— Locally throughout the State; most common in the eastern and southern parts. HABITAT — Prefers well drained soil but will grow on most of our soils. Generally prevalent but most common and thrives best in low, moist, and rather fertile situations. Usually found in the understory of the forest. IMPORTANCE OF THE SPECIES — The Flowering Dogwood is valuable for ornamental pur- poses and for its wood. Few trees surpass it in beauty when in bloom and when fruiting. In this State it does not reach a sufficient size to be of commercial importance. It should be maintained in our forest on account of its beauty and its value as a soil improver, since it is very tolerant and will grow readily in the understory of the forest. PLATE CXVI. FLOWERING DOGWOOD. 1. A flowering branch, with three clusters of flowers, each surrounded by a showy 4-bracted white involucre, x J. •1. A single flower, enlarged. 3. A fruiting branch with mature leaves, x i. !. A winter twig with two terminal spherical flower buds, x \. 5. Terminal section of a winter twig showing leaf-scars and leaf-buds, enlarged. PLATE CXVII. ALTERNATE-LEAVED DOGWOOD, 1. A flowering branch, x 5. 2. A fruiting branch, x 4. 3. A winter twig, natural size. 4. Terminal section of a winter twig, enlarged. 205 ALTERNATE-LEAVED DOGWOOD. Cornus alternifolia, Linnaeus. FORM— A small tree usually about 10-20 ft. high but may reach a height of 30 ft. with a diameter of 8 inches. Trunk is short. Crown broad, deep, flat-topped,, and dense. BARK — Rather thin; on younger stems greenish streaked with white, and smooth; on older stems reddish-brown and roughened by shallow longitudinal fissures which are sometimes joined transversely. TWIGS — Alternate, rather slender and flexible, smooth, often glossy, at first reddish- green, later dark green and often striped with white; bitter to the taste and emitting an offen- sive smell if punctured; marked with lunate leaf -scars and scattered lenticels. BUDS — Alternate, rarely opposite, oval, sharp-pointed, covered with a few, usually 2-3, chest- nut-brown scales. Outer scales are often separated towards apex. LEAVES — Alternate, sometimes opposite, simple, frequently clustered at end of branches, 3-5 inches long, 2-3 inches wide, ovate, acuminate at apex, wedge-shaped at base, entire or wavy on margin, bright green above, usually almost white downy below. LEAF-SCARS — Alternate, sometimes opposite, situate on extensions of the twigs, with their surfaces often at right angles to twigs; in outline resemble the moon in first quarter and containing 3 bundle-scars. FLOWERS — Appear about April. Cream-colored, perfect, borne in many-flowered terminal cymes. FRUIT — A dark blue spherical drupe, J of an inch in diameter, tipped with remnants of the style, borne in cymes. Ripens in October. WOOD — About the same as the flowering dogwood, but no uses of it are reported. DISTINGUISHING CHARACTERISTICS— The Alternate-leaved Dogwood, also known as Blue Dogwood, Purple Dogwood, Green Osier, and Pigeon-berry, may be distinguished by its alternate branching, reddish-green to dark green twigs, cream-colored flowers and dark blue fruit arranged in cymes. It does not have the alligator bark of the Flowering Dogwood and usually frequents moister habitats. RANGE — Nova Scotia to Alabama, and westward to Minnesota. DISTRIBUTION IN PENNSYLVANIA— Throughout the State. Common in the portions which are well watered. HABITAT — Prefers moist well drained soil. Most common along streams and other bodies of water and border of woodlands. Very tolerant of shade. IMPORTANCE OF THE SPECIES — The Alternate-leaved Dogwood is of little commercial importance. It is very pretty and may be of value as a soil-conserver and improver. 206 BLACK GUM. Nyssa sylvatica, Marshall. GENUS DESCRIPTION — The genus Nyssa is rather limited in its distribution being confined to the eastern United States and southern Asia. It comprises 7 species in the world 5 of which are native to North America and 1 to Pennsylvania. All the representatives produce wood which is very tough on account of its twisted and contorted grain. FORM — Usually a medium-sized tree with a Leight of 15-40 ft., but may reach a height of 106 ft. with a diameter of 5 feet. Trunk straight and rather continuous. Many lateral branches are horizontal; some of the lower are drooping and the upper ascending. Old trees often have a low Hat crown but have their middle and lower trunk covered with small horizontal branches. BARK — Grayish, smooth to scaly on young trunks; reddish-brown to grayish-black, very rough and scaly on older trunks. Forms what is known as alligator bark on very old trunks characterized by quadrangular and hexagonal blocks. See Fig. 100. TWIGS — Smooth, with few lenticels, grayish to reddish-brown; pith rather large, white, separated by layers of stone cells which may be seen with magnifying glass. BUDS — Alternate, ovate, reddish-brown, J of an inch long, usually smooth, covered by 3-5 visible, ovate, closely overlapping scales. Lateral buds sometimes superposed, smaller than terminal one. Buds originate close to leaf-scar and occasionally protrude into it. LEAVES — Alternate, simple, oval, 2-5 inches long, acute at apex, wedge-shaped at base, entire and slightly thickened on margin, dark green and shiny above, often hairy below, turning to a gorgeous red in fall. LEAF-SCARS — Alternate, conspicuous, rather large, broadly crescent-shaped, with three single or 3 groups of bundle scars, which are conspicuous on account of size; brownish in color, contrasting with lighter surface of the leaf-scar. FLOWERS— Appear in May or June. Borne on long slender somewhat downy stalks. Sta- minate And pistillate flowers separate. Slaminate occur in dense many-flowered heads; pistillate in open few-flowered clusters. FRUIT — A small, dark blue, fleshy berry or drupe, ovoid, § of an inch long, 1-3 in a cluster, often with a few remnants of undeveloped pistillate flowers at base. Borne on long stalks. Ripens in Octobei. WOOD — Diffuse-porous; rays indistinct; growth-rings usually indistinct; pores numerous, small, uniform in si/e and distribution; wood cross-grained, tough to split, diflicult to work, not hard, moderately strong and stiff, not durable, light yellow. Weighs 36.91 Ibs. per cubic foot. Used for hubs of wheels, boxes, ironing boards, rolling pins, chopping bowls, excelsior, broom handles, baskets, and berry crates. DISTINGUISHING CHARACTERISTICS— The Black Gum, also known as Sour Gum, Tupelo, and Pepperidgn, can be distinguished by its alligator bark when old, grayish to reddisli-brcnvu smooth clear twigs when young which are marked with conspicuous leaf-scars with three bundle-scars. The buds diverge very much from the twigs and may be superposed. Lateral branches on young trees often take a horizontal position. The separation of the pith by stone cells, the gorgeous red color of the autumnal foliage, and the bluish berries also aid in recognizing it. RANGE — Maine to .Tampa Bay, Florida; west to southern Ontario and Michigan, southward to Texas. DISTRIBUTION IN PENNSYLVANIA— Very common in the eastern, central, and southern parts, local in western part, rarer in northern part. Reaches large size in swamps of Adams and Franklin counties. HABITAT — Found in variable habitats. Very c-omnion on burnt-over areas, on dry mountain slopes, abandoned fields, abandoned charcoal hearths; but reaches its best development along streams and in low wet situations. While it lias preferences it is not a chooser of habitats. IMPORTANCE OF THE SPECIES— The Black Gum has been despised since the early farmers tried to split it for fence rails. It is slowly gaining favor, but is not of suflicient importance to be recommended for forest planting. Its autumnal foliage is beautiful and in winter the form of young trees is very attractive. PLATE CXVIII. BLACK GUM. 1. A pistillate flowering branch, x 5. 2. A staminate flowering branch, x J. 3. A fruiting branch with mature leaves, 4. A winter twig, natural size. 5. Section of a winter twig, enlarged. x 1. PLATE CXIX. MOUNTAIN LAUREL. 1. Flowering branch with (i) immature leaves, (m) mature leaves, and with open and closed blossoms, x i. '2. Branch with mature leaves and mature fruit, x J. 3. A fruit, enlarged. 207 MOUNTAIN LAUREL. Kalmia latifolia, Linnaeus. FAMILY AND GENUS DESCRIPTION— The Heath family, Ericaceae, embraces species which are amongst our best known and most popular shrubs. The Huckle-berries, Blueberries, Cran- berries, Azaleas, Kalmias, and Rhododendrons are some of the commonest representatives. Very few representatives are of any special t-conomic value on account of the wood which they produce. Some are important on account of their aesthetic value, while others yield valuable food or are used in medicine. This family comprises about 90 genera with more than 1,400 species, of which number about 40 gvnera are found in the United States, 7 of which have tree representatives. The flora of Pennsylvania comprises 27 genera with about 45 species. Since most of them are shrubs only 3 species representing 3 genera are described here. The genera here described are Kalmia, Rhododendron, and Oxydendrum. The genus Kalmia comprises 5 or G species in North America and Cuba. The species described on this page is the only one which reaches tree-size. Two other shrub species, Sheep Laurel (Kalmia angustifolia L.) and Swamp Laurel (Kalmia polifolia Wang.), are also native to this State. The genus is named after Peter Kalm, a Swedish naturalist, who traveled in North America during the middle of the 18th century. FORM — In Pennsylvania usually a shrub 5-10 ft. in height with a stout stem which is usually forked, often inclined and bearing divergent branches which form a round compact head. In the South it reaches a height of 30-40 ft. with a diameter of 20 inches. BARK — Very thin, reddish-brown, furrowed, peels off into long, narrow, thin scales ex- posing cinnamon-red inner bark. TWIGS — At first reddish-green covered with viscid hairs, later becoming decidedly green, and finally brown. Rather smooth except where roughened by leaf-scars and bud-scale scars. BUDS — Alternate, ovate, sharp-pointed, greenish in color. Leaf-buds are formed early and appear below the clustered flower-buds. Flower-buds are covered by numerous, downy and over- lapping green scales which arc coated with glandular hairs and enlarge with the developing shoot in spring. LEAVES — Alternate, sometimes paired, simple, oblong, wedge-shaped at base, «nt)ire- margined, acute at apex sometimes tipped with bristle point, 3-4 inches long, about J of an inch wide. Mature leaves are thick, leathery, dark green, glossy above, yellowish-green below, and persist for two seasons. LEAF-SCARS — Large, imbedded in twig, with a cluster of bundle-scars. FLOWERS — Emerge from flower buds which begin to expand in early spring and open about May or June. Flowers are borne on red or green scurfy stalks and arranged in dense many- flowered corymbs which have a diameter of about 4 inches. Calyx is divided into five parts. Corolla is white to rose-colored and viscid pubescent. FRUIT — Matures about September. It is a ciany-seeded woody capsule, roundish in outline but slightly five-lobed and covered with viscid hairs. Both style and calyx persist. Each capsule produces many seeds. WOOD — Diffuse-porous; heavy, hard, strong, rather brittle. Heartwood reddish-brown, sapwood lighter colored. Weighs 44.02 Ibs. per cubic foot. Where it grows to a fair size it is an excellent wood for fuel. It is also used in manufacture of tool handles, penholders, bucket handles, turnery, and tobacco pipes. About 85,000 Ibs. of this wood are produced annually in North Carolina for pipes. DISTINGUISHING CHARACTERISTICS— The Mountain Laurel, also known as Kalmia and Calico-Bush, is one of our few broad-leaved species whose leaves persist over winter. It can be distinguished from all other species native to this State by its thick leathery leaves which are 3-4 inches long, persistent, decidedly glossy on upper surface and yellowish-green on lower surface. The Great Laurel or Rhododendron is also evergreen but its leaves and buds are much larger than those of the Mountain Laurel. The leaves of the Mountain Laurel are shorter, narrower, and sharper-pointed than tnose of the Rhododendron. RANGE — New Brunswick south generally along the mountains to Florida, west to Arkansas. DISTRIBUTION IN PENNSYLVANIA— Throughout the State. Most common in the moun- tainous parts, where it often forms almost impenetrable thickets. HABITAT — Common along margins of swamps and as an understory in deciduous forests. Also found on hillsides and hilltops. Very common on rocky and round hilltops. IMPORTANCE OF THE SPECIES— The Mountain Laurel remains too small in this State to be of commercial importance on account of the wood which It produces. Next to Rhodo- dendron, it is the most attractive native shrub found in our flora. It is a favorite with lovers of the woods who admire not only its blossoms, but also its leaves and its habit of growth. 208 GREAT LAUREL. Rhododendron maximum, Linnaeus. GENUS DESCRIPTION — The name Rhododendron is of Greek origin and means Rose tree. It comprises about 100 species of shrubs and a few small trees in the northern hemisphere. About 10 species are native to North America and 1 to Pennsylvania. FORM — A shrub or small bushy tree. In this State usually a shrub from 5-12 ft. in height, but in the mountains of the South it may reach a height of 35 feet. Stems often twisted, bearing contorted branches which form an irregular round head. BARK — Thin, reddish-brown, at first close, later peeling off into thin scales. TWIGS — At first green and coated with rusty pubescence but become smooth during first winter, and gradually turn to bright red-brown. BUDS — Alternate; leaf-buds and flower-buds distinct. Leaf -buds usually axillary sometimes terminal, dark green, cone-shaped, form in midsummer. Flower-buds usually terminal, cone- shape, 1-li inches long, covered by numerous, overlapping, green bracts. LEAVES — Alternate, simple, persistent, clustered at apex of branches, ovate to oblong, acute at apex, rounded to wedge-shaped at base, entire on margin, 4-11 inches long, 1J-2J inches wide, thick, leathery, smooth and dark green on upper surface, whitish on lower surface. LEAF-SCARS — Alternate, slightly raised, conspicuous, rounded at base, slightly depressed at top, with several bundle-scars arranged in a U-shaped line. FLOWERS — Appear about June after the new leaves are fully developed, are arranged in umbel-.like clusters about 4-5 inches in diameter and borne on glandular pedicels. Individual flowers are perfect, pale rose to white in color; upper petals marked by yellowish-green dots. FRUIT — A dark reddish-brown capsule about 5 of an inch long, which persists until the following season. Capsules split open lengthwise liberating oblong flattened seeds. Surrounded at the base by persistent calyx and terminated by persistent linear style. WOOD — Diffuse-porous; hard, strong, brittle, light brown with lighter sapwood. "Weighs 39.28 Ibs. per cubic foot. Of little commercial use but occasionally toanufactured into tool handles and engraving blocks. Excellent for fuel where it reaches a fair size. DISTINGUISHING CHARACTERISTICS — The Great Laurel, also known as Rhododendron and Rose Bay, can be distinguished from all other species of trees native to Pennsylvania by its large, persistent, leathery, simple leaves which are clustered towards the end of the branches and alternate ir their arrangement. Its shrubby form and its preference for moist habitats also aid in distinguishing it. The conical flower-buds, which are usually terminal and often over an inch long, are also characteristic. The twigs are evidently marked by the bud-scale scars. »'• RANGE — Nova Scotia and. Lake Erie on the north, south along the mountains to northern Georgia. DISTRIBUTION IN PENNSYLVANIA— Found throughout the State. Rare in the southeastern part. Abundant throughout the mountainous parts. HABITAT — In the North frequents a cold swampy situation. In the South it ascends the mountains to 3,000 feet but remains along the banks of streams. Tolerates most soils except limestone. IMPORTANCE OF THE SPECIES — The "Rhododendron does not reach a large enough size in Pennsylvania to produce wood of commercial importance. In the South it often becomes a tree. It is the most attractive shrub in our flora, and will thrive in a variety of situations but prefers moist locations and flees from soils which contain lime. PLATE CXX. GREAT LAUREL. 1. Branch with mature and immature leaves, and a cluster of open flowers, x J. 2. A fruiting branch with a large terminal bud, x i. 3. Cross-section of a fruit capsule showing five cells, natural size. PLATE CXXI. SOUR-WOOD. 2.' A ?e°w ^S?fme5aS5hfroltI1 x°lf °ne-sided racemes of flowers clustered in an open panicle, x J. 4! A^intei^twig* Inl°arg8eile Sb^wing flve cells filled with seeds' 5. Section of a winter twig, enlarged. enlarged. 209 SOUR-WOOD. Oxydendrum arboreum, (Linnaeus) De Candolle. GENUS DESCRIPTION — The Sour-wood is the sole representative of the genus Oxydendrum. The word Oxydendrum means acid tree, in allusion to the acid foliage. FORM — A medium-sized tree which may reach a height of 50-60 ft. with a diameter of 20 inches, but usually is about 25 ft. in height with a diameter of 8 inches. Trunk usually straight, tall, slender, and bears a narrow round-topped crown. BARK — Rather thick, roughened by fissures which separate rounded ridges covered with thick scales. On old trunks grayish often tinged with red; on young branches reddish-brown. TWIGS — Rather slender, at first yellowish-green, later orange-colored and reddish-brown. Marked with numerous, oblong, elevated lenticels. BUDS — Alternate, axillary; terminal buds absent; small, partly imbedded in the bark, acute at apex, covered with several opposite dark red scales. LEAVES — Alternate, simple, oblong, stalked, acute at apex, wedge-shaped at base, serrate on margin, very smooth, 5-7 inches long, l$-2i inches wide. LEAF-SCARS — Alternate, elevated, nearly triangular, with a single compounded bundle-scar. FLOWERS — Appear about July. White, perfect, with cylindrical corolla, and borne in racemes often 6-8 inches long. FRUIT— A 5-sided, ruvalved capsule terminated by a persistent style. Matures in September only a month or six weeks after the flowers. Capsules often persist in clusters. WOOD — Diffuse-porous; hard, heavy, compact, reddish-brown with lighter sapwood. Medullary rays are numerous but narrow. Weighs 46.48 Ibs. per cubic foot. Used locally for runners of the Appalachian tanbark sleds, and for tool handles. DISTINGUISHING CHARACTERISTICS — The Sour-wood, also known as Sorrel-tree and Sour Gum, can be distinguished in summer by its white bell-shaped flowers which are arranged in racemes resembling the lily-of-the-valley. The alternate bitter leaves which resemble the peach leaf are also characteristic. The bark on older trees resembles that of the Black Gum. The winter buds, which are dark red, alternate, very small, often partly inbedded by bark, are also characteristic. RANGE — Pennsylvania and Indiana south to Florida and western Louisiana. DISTRIBUTION IN PENNSYLVANIA— Found only sparsely in the southeastern part of the State. HABITAT — Usually frequents well-drained soils. Commonly found on hillsides, seldom along streams. IMPORTANCE OF THE SPECIES — The Sour-wood is native only to a very small portion of southern Pennsylvania. Its small size and limited distribution in this State prevent it from being recommended for fores-trj purposes. It is, however, an attractive ornamental tree on account of its form, ia*e flowering, beautiful and attractive autumnal foliage. 14 210 COMMON PERSIMMON. Diospyros virginiana, Linnaeus. FAMILY AND GENUS DESCRIPTION— The Ebony family, Ebenaceae, is widely distributed iu the tropics, and only a few representatives are found in the temperate regions. It comprises about 6 genera with more than 250 species. The most important genus is Diospyros which has 2 representatives in the flora of the United States and 1 in Pennsylvania. This genus comprises about 160 species found mostly in the tropics. Members of this genus produce some of the ebony of commerce, and valuable foods in China and Japan. The species described below is the sole representative of this genus in eastern North America. One other species is found in the southern and western parts of Texas. FORM — A small tree usually from 25 to 50 ft. in height with a diameter of less than ID inches, but may reach a height of 100 ft. with a diameter of 2 feet. Trunk usually short and slender. Crown high and broad-topped. It often spreads by roots migrating under the ground, forming dense thickets. BARK — On old trunks thick, hard, dark gray to dark brown or black, cinnamon-red at the bottom of the fissures; separates into thick squarish blocks which peel off into thin scales. See Fig. 101. TWIGS — Slender, bittar, astringent, grayish to reddish-brown becoming darker in second year, usually pale pubescent, covered with a few scattered orange-colored lenticels, and contain large pith or pith chamber. BUDS— Alternate, broadly ovate, closely pressed against twig, i of an inch long, sharp- pointed, covered by 2 dark brown glossy scales; terminal bud absent. LEAVES — Alternate, simple, oval, acute at apex, entire on margin, wedge-shaped to heart- shaped at base, 4-6 inches long, thick, dark green and shiny above, often hairy below. Leaf- stalks are J-l inch long, and contain 1 flbro-vascular bundle. LEAF-SCARS — Alternate, elevated, flattened, contain 1 prominent bundle-scar which is trans- versely-elongated, or several becoming confluent. FLOWERS — White, appearing about May or June. Staminate and pistillate flowers occur separate. Staminate arranged in 2-3-flowered cymes. Pistillate solitary, and borne on short stalks. FRUIT — A juicy, spherical, orange-colored, often red-cheeked berry with remnants of style persisting and seated in enlarged green calyx. Often very astringent. Sometimes edible be- fore frost appears. Contains from 1-8 seeds, usually 4-6. WOOD — Diffuse-porous; heavy, hard, compact, susceptible to a high polish, strong; heart- wood is brown to black but usually forms late; sapwood is wide, yellowish and often streaked with black. Weighs about 49 Ibs. per cubic foot. Used for shuttles, gold heads, billiard cues, mallets, parquet flooring, brush backs, veneer. DISTINGUISHING CHARACTERISTICS — The Persimmon, also known as Date-plum and Pos- sum-wood, can be distinguished in summer by its alternate, simple, entire-margined, deep green leaves with only 1 nbro-vascular bundle in the leaf-stalk and the rough bark which is often broken up into quadrangular blocks and is evidently cinnamon-red at the base of the . fissures. In autumn the fruit is characteristic. In winter the rough bark with cinnamon-red color at the bottom of the fissure, the semi-orbicular leaf-scars with only 1 bundle-scar, the broadly ovate buds with 2 dark brown scales, the reddish-brown slightly pubescent twigs with relatively large pith or pith cavity, and the persistent remnants of flowers are distinctive. RANGE — Connecticut to Florida, westward to Iowa and Texas. DISTRIBUTION IN PENNSYLVANIA — Common in the eastern and southern parts of the State. Abundant on Gettysburg battlefield. Local in southwestern part of the State. Absent in the higher mountainous parts. HABITAT — Prefers a light, somewhat sandy well-drained soil. Tolerates rich bottomlands especially in the South. IMPORTANCE OF THE SPECIES — The Persimmon is too small in size and too limited in dis- tribution in this State to be of commercial importance from the point of view of wood produc- tion. It is essentially a southern tree. The tree has an attractive form, beautiful clean foliage, and an exceptionally attractive bark. It rarely exceeds 40 feet in height with a diameter of 12 inches in this State. PLATE CXXII. COMMON PERSIMMON. 1. A branch with pistillate flowers, x J. 2. A branch with staminate flowers, x J. 3. A fruiting branch with mature leaves, x 4 4. A winter twig, natural size. 5. Section of a winter twig, enlarged. PLATE CXXIII. CATALPA. 1. A pfir.Kle ot Mowers, x J. •_'. A uiuiich with two drooping cigar-like fruits, the one split open shewing the 3. A winged seed, x |. 4. A winter twig, x i. See Plate II. , x J. 211 CATALPA. Catalpa bignonioides, Walter. FAMILY AND GENUS DESCRIPTION— This tree belongs to the Bignonia family, Bignoni- aceae, which comprises about 100 genera with 1,500 species. Most of the representatives of this family occur in the tropics; only a few are found in the temperate zone. They occur as trees, shrubs, woody climbers, or rarely herbs. North America has only 6 genera with 8 species in its flora and Pennsylvania 3 genera with 3 species. The genus Catalpa is the only one which has tree representatives occuring rather frequently in this State. This genus comprises about 7 species in the world, of which number 2 are native to North America. No representative of this genus is native to Pennsylvania but 1 species has been naturalized so extensively in every part of the State, that a description of it in this publication was considered desirable. FORM— Usually 25-40 ft. high but may reach a height of 60 ft., with a diameter of 3 feet. Trunk usually short, crooked, often angular, and unattractive. Crown high, broad, and rather • symmetrical in appearance in summer, due to the dense foliage. BARK — Light brown, rather thin, shallowly-ridged, scaly, bitter. TWIGS — Stout, smooth, or slightly downy, yellowish-brown, usually frozen back, covered with numerous large lenticels, roughened by leaf-scars. Pith large, white sometimes chanJbered at the nodes. See Plate II, 2. EUDS — Terminal bud usually absent. Lateral buds small, almost inbedded in bark, usually less than i of an inch long, covered with 5-6 visible, small, brown bud-scales. LEAVES — Opposite or whorled i. e., more than two at a node, simple, 6-10 inches long, 4-5 inches broad, ovate, heart-shaped at base, acute at apex, entire or wavy on margin. Fall simultaneously after first heavy frost. LEAF-SCARS — Opposite or 3 at a node, large, conspicuous, with projecting margin, elliptical in outline, with conspicuous bundle-scars usually arranged in an ellipse. FLOWERS — Appear in June or July. Perfect, arranged in many-flowered crowded panicles from 8-10 inches long. Corolla is conspicuously spotted on inner surface. FRUIT — A long, cylindrical, bean-like capsule which often persists far into winter and con- tains many flattened winged seeds. Wings surround seeds and are fringed at ends. Tree is sometimes called Indian Bean on account of fruit. WOOD — Ring-porous; distinct demarcation between heartwood and sapwood; odor somewhat like kerosene; light, soft, coarse-grained; durable in contact with soil, light brown, and has a satiny surface. Weighs about 26 Ibs. per cubic foot. Used mainly for cross-ties, posts and poles. DISTINGUISHING CHARACTERISTICS — The Eastern Catalpa, also known as Catalpa, Indian Bean, and Cigar Tree, can be distinguished in summer by its leaves which are opposite or whorled and its large panicles of flowers. The cigar-like or bean-like fruit is characteristic in autumn and winter. In winter it can be distinguished by its large elliptical leaf-scars which are opposite or whorled and have their bundle-scars arranged in an ellipse. The pith is sometimes chambered at the nodes. The Eastern Catalpa closely resembles the Western Catalpa but has slenderer and thinner walled fruit, larger flower-clusters, more distinct markings on inner surface of corolla, and more blunt-pointed leaves. The Western Catalpa is more frost hardy than the Eastern Catalpa. RANGE — Original range was limited to parts of Georgia, Alabama, Mississippi and Florida. At present found in all parts of the country east of the Rocky Mountains and as far North as New England. DISTRIBUTION IN PENNSYLVANIA — Planted for ornamental purposes in many parts of the State and has escaped cultivation in practically every part of the State. Individual specimens or small groups of trees are common in the forest near settlements. HABITAT — Prefers moist and fertile situations, is most common along streams and river banks, but also found in drier places. Prefers shaded to open situations. IMPORTANCE OF THE SPECIES — Two species of Catalpa are commonly recognized, the Eastern Catalpa and the Western or Hardy Catalpa. Both have been widely advertised. The Western species is hardier against frost and produces a straighter and cleaner trunk. Neither of the 2 species should be planted for forestry purposes in this State. Both species produce beauti- ful flowers and foliage and attractive fruit. 212 THE OLIVE FAMILY— OLEACEAE. The Olive family comprises representatives which are widely dis- tributed in temperate and tropical regions, but are . commonest in the northern portion of both hemispheres. A great variety of trees and shrubs is embraced by this family, some of which are valuable timber trees, while others are valuable for ornamental purposes or for the food which they yield. The most important is the Olive Tree (Olea Europaea, L.), whose fruit and the oil derived from it are used almost universally as food. The Olive Tree was cultivated in ancient times in Syria and Palestine; later it was introduced into the Mediterranean region, where one can find large orchards of it at the present time; and within the past few decades it has been intro- duced on a large scale into the southwestern part of the United States^ A few specimens are also growing at the present time near Mont Alto, Pennsylvania. The Ashes which are among our most valuable timber trees, the Forsythias and Lilacs which are among our most attractive and popular shrubs, and the Privets, which are used so extensively as hedge plants, are also members of this family. The Olive family comprises about 21 genera with 500 species of trees, shrubs, and a few herbs. The flora of North America contains 5 genera with about 20 species, while that of Pennsylvania contains 4 genera with 9 species. Only 2 of the 4 genera native to Pennsyl- vania have tree representatives. KEY TO THE GENERA. Page. 1. Leaves compound; fruit a dry samara; flowers without a corolla; winter buds with 3-4 pairs of scales, Fraxinus 213 1. Leaves simple; fruit a fleshy berry; flowers with a corolla; winter buds with more than 4 pairs of scales, ...Chionanthus 217 THE ASHES— FRAXINUS, (Tourn.) L. The Ashes with one or two exceptions are trees, which occupy a variety of situations but prefer rich, moist soil. Some species may also be found occasionally in swamps or along streams, while others frequent dry and poor uplands. The trees are usually straight, have little stem taper, and often attain large dimensions. They are, lo- cally, rather abundant and yield wood which is straight-grained, strong, and elastic. The wood of all the eastern species except that of the Black Ash, is sold as White Ash. This classification is legi- timate since there is little difference for practical purposes. They are also valuable as shade trees. Our native species and the intro- duced European species (Fraxinus excelsior, L.) are planted rather extensively in parks and lawns. The trunk and leaves of Fraxinus ornus, L., a species of southern Europe and Asia Minor, yield the manna of commerce. The Ashes may be regenerated by natural and artificial methods. The natural regeneration may be accomplished by means of regulated 213 cutting of the mature trees accompanied by the establishment of a young growth from the seed scattered by the seed trees which remain, or by means of coppicing. Coppicing is a practical method of regen- eration especially on rich, moist soils and where very large sizes are not required. The artificial regeneration may be accomplished by sowing seeds, or what is still better, by collecting the seeds, planting them in the nursery, and after a year's growth in the nur- sery, lifting them and planting them out upon the area where they are to remain and produce a timber crop. The leaves of the Ashes are opposite and compound. The leaf- lets occur in 2s opposite each other along the principal leaf-stalk with a single leaflet at the end, hence the total number of leaflets is always odd. The twigs are stout and occur in pairs opposite each other along the main axis. The branchlets are usually flattened at the nodes. The flowers are produced in dense clusters and usually appear in spring before the leaves have made their appearance. The fruit, known as a samara, matures in fall and occurs in clusters. The individual seed is winged at one end. This wing aids in the dis- persal of the seed by the wind, which is the most important disper- sing agent; but water may also scatter a large quantity of the seeds, especially of such species which are commonest near streams or where flood waters occur. The Ashes are distributed throughout the north temperate zone and comprise about 40 known species, of which number 16 occur in North America and 4 in Pennsylvania. Three species are common in this State, while another species known as the Biltmore Ash (Fraxinus Biltmoreana, Beadle), is found locally only over a limited region in the southern part of the State. A variety of the Eed Ash known as the Green Ash (Fraxinus pennsylvanica var. lanceolata) is also found locally in the southern part of the State. SUMMER KEY TO THE SPECIES. Page. 1. Leaves with sessile leaflets; seed surrounded by wing; bark scaly, not furrowed with diamond-shaped fissures, F. nigra 215 1. Leaves with stalked leaflets: seed partly surrounded by wing; bark furrowed with diamond-shaped fissures 2 2. Leaves and twigs smooth or nearly so; seed usually winged only at apex F. americana 214 2. Leaves and twigs velvety pubescent; seed winged usually at apex and sides, F. pennsylvanica 216 WINTER KEY TO THE SPECIES. 1. Buds usually black and acute at apex; bark scaly, not furrowed with diamond- shaped fissures; tall and slender, F. nigra 215 1. Buds rusty to dark brown, usually obtuse at apex; bark furrowed with diamond- shaped fissures; tall but stout 2 2. Twigs smooth or nearly so; leaf-scars evidently indented on upper margin, F. amiericana 214 2. Twigs velvety pubescent; leaf -scars not evidently indented on upper surface, F. pennsylvanica 216 214 WHITE ASH. Fraxinus americana, Linnaeus. FORM— Usually reaches a height of 70-80 ft. with a diameter of 2-3 ft., but may attain a height of 120 ft. with a diameter of 5-6 ft. Trunk usually tall, massive, clear from branches for a considerable distance from the ground when grown in the forest, bearing a narrow, some- what pyramidal crown. When open grown the crown is decidedly round-topped and often extends almost to the ground. In forest grown trees trunk often continuous and dividing into a number of spreading branches. BARK — Grayish-brown, rather thick upon older trunks, decidedly divided by diamond-shaped fissures into rather flattened ridges which are covered by thin, close-fitting scales. Longitudinal ridges often transversely-fissured so that the primary fissures are connected. See Fig. 86. TWIGS — Opposite, stout, usually smooth, sometimes covered with a slight bloom, decidedly flattened at the nodes. During the first winter grayish-brown in color, and decidedly lustrous; covered by scattered, large, pale lenticels. BUDS — Opposite, ovate, blunt-pointed, usually dark brown, occasionally almost black. Term- inal bud larger than laterals, covered by 2-3 pairs of visible scales which occur opposite each other. Scales on the terminal buds may be somewhat sharp-pointed, while those on the lateral buds are usually obtuse. Two lateral buds are usually found 'at base of terminal bud causing a terminal enlargement of twig. LEAVES — Opposite, compound, about 10 inches long with 5-9 leaflets. Leaflets 3-5 inches long, about 15 inches broad, evidently-stalked, slightly serrate on margin, acute at apex, wedge-shaped to rounded at bas'e. When full grown usually smooth and dark green above and pale below. A few hairs are sometimes found along the veins on the lower surface. LEAF-SCARS — Opposite, semi-circular in outline, notched on the upper margin, raised, con- spicuous; bundle-scars small, numerous, arranged in a curved line. FLOWERS — Appear about May before the leaves. The staminate and pistillate on different trees. Staminate occur in dense reddish-purple clusters: pistillate in rather open panicles. FRUIT— -A samara borne in dense drooping panicles about 7 inches long. Panicles often persist far into winter. Individual samara 1-2 inches long, consists of a seed bearing portion and a winged portion. Seed portion round in cross-section, terminated by the wing which aids in the dispersal of the seed. Since some trees bear staminate flowers only, seeds are never found upon them. Trees bearing pistillate flowers alone produce seeds. WOOD — Ring-porous; very heavy and strong, odorless and tasteless, tough, elastic, and brown, with thick and much lighter colored sapAvood. Pores in spring wood large, usually 3-10 rows wide. Pores in summer wood isolated or in groups of 2-3, and usually joined by wood paren- chyma. Weighs 40.77 Ibs. per cubic foot. Used in the manufacture of agricultural implements, wagon building, furniture, interior finishing of houses, and for tool handles. DISTINGUISHING CHARACTERISTICS — The White Ash, also known as the Canadian Ash, can be distinguished from the Black Ash by its leaves, which have stalked leaflets, while the leaflets of the Black Ash arc sessile. The buds of the White Ash are usually obtuse and brown in color, while those of the Black Ash are usually acute and black in color. The bark of the White Ash is usually furrowed and has diamond-shaped fissures between the ridges, while the bark of the Black Ash is scaly, often corky and not furrowed. It can be distinguished from the Red Ash by its smooth leaves and twigs. Those of the Red Ash are usually velvety-pubescent. The leaf -scars of the White Ash are usually evidently-indented in the upper margin, while those of the Red Ash are not. The seeds of the White Ash have wings which are fastened only to the apex of the seed, while in the Red Ash they are fastened to the apex and often extend down along the sides, and in the Black Ash the wing usually surrounds the seed. RANGE — Nova Scotia to Minnesota and southward to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA— Generally distributed throughout the State. Common in the eastern, southern, and western parts. Sparse in the mountainous parts, except in moist valleys and rich bottomlands. HABITAT — Prefers fertile, moist soils; very common in rich, moist woods and along streams, lakes, and other bodies of water. Occasionally found on rather dry hillsides. IMPORTANCE OF THE SPECIES— The White Ash is one of the most important timber trees of Pennsylvania on account of the large size which it attains, its general distribution through- out the State, its rapid growth, as well as its immunity from the attack of fungous diseases and insects. Nature did not produce it in pure stands, hence in developing our future forests we should aim to follow nature and plant White Ash in mixture with some other desirable species. White Ash and White Pine will undoubtedly prove to be a valuable mixture. PLATE CXXIV. WHITE ASH. 1. A branch with a cluster of staminate flowers and immature leaves, x 2. A panicle of pistillate flowers, x J. 3. A mature compound leaf, x J. 4. A cluster of fruit, x j. 5. A winter twig, x i. 6. Section of a winter twig, enlarged. PLATE CXXV. BLACK ASH. 1. Branch with staminate flowers, x \. 2. A panicle of pistillate flowers, x \. 3. A mature compound leaf, x J. 4. A cluster of fruit, x \. 5. A winter twig, x J. 6. Section of a winter twig, enlarged. 215 BLACK ASH. Fraxinus nigra, Marshall. FORM — A medium-sized tree which usually attains a height of 60-80 ft. with a diameter of 1-2 ft., but may reach a height of 100 ft. with a diameter of 2£ feet. It usually has a rather tall, slender trunk often free from branches for a considerable distance from the ground bearing a narrow and shallow crown formed by numerous rather upright branches. Usually found in the forest, where the slender form prevails, but occasionally may be found in the open, where its form resembles that of the White Ash. BARK — Thin, grayish, shallowly and irregularly fissured; ridges between the fissures decidedly scaly rnd somewhat corky. By rubbing the bark it breaks up into a very fine powder. See Fig. 87. TWIGS — Rather stout, at first somewhat hairy, but soon becoming quite smooth. Resemble those of the White Ash but lighter in color, and not so smooth and glossy. BUDS — Opposite; terminal bud present, ovate, sharp-pointed, black, covered with 1-2 pairs of visible bud-scales, usually at some distance from nearest lateral buds; lateral buds usually almost as broad as long, often obtuse at apex, closely oppressed to twigs. LEAVES — Opposite, compound, about 14 inches long, with 7-11 sessile leaflets. Leaflets are all sessile except the terminal one, 3-5 inches long, about 1J inches wide, acute at the apex, serrate on the margin, wedge-shaped at the base, dark green and smooth above, paler below. LEAF-SCARS — Opposite, large, conspicuous, crescent-shaped, .upper margin usually straight or convex; bundle-scars numerous arranged in a curved line, sometimes joined so as to form a compound scar. Q FLOWERS — Appear about May before the leaves. Staminate and pistillate borne on the same or different trees; the stamina te in dense, dark purplish clusters; the pistillate in rather open panicles. « FRUIT — A samara which resembles the fruit of the White and Red Ashes, but differs in that the wing is broader, decidedly notched at the apex, and completely surrounds the somewhat flattened seed bearing portion. WOOD — Ring-porous; heavy, smooth, soft, not strong, rather coarse -grained, somewhat dur- able. Heartwood dark brown with white sapwood; marked difference between spring and sum- mer wood; annual layers of the wood easily separated. Pores in spring wood in a broad zone often comprising one-half of the ring. Pores in summer wood large, few, scattered. Weighs 39.37 Ibs. per cubic foot. Used in the manufacture of baskets, hoops, chair bottoms, and the interior finishing of houses. DISTINGUISHING CHARACTERISTICS— The Black Ash, also known as Hoop, Swamp, Basket, and Brown Ash, can readily be distinguished from all the other species of Ash in Pennsylvania in summer by its opposite and compound leaves with sessile leaflets. The leaflets of all other species of Ashes are evidently-stalked. In winter it can be recognized by its black and acute buds, its scaly, non-fissured bark, and its tall and slender form. In autumn by its fruit with a flattish body which passes insensibly into the wing. RANGE — Newfoundland to Manitoba, south to Virginia and Arkansas. DISTRIBUTION IN PENNSYLVANIA— Generally distributed over the State. Common in the eastern, southern, central and western parts. Rare in mountainous portion except in moist valleys. HABITAT — Prefers swampy habitats, in this respect differing very much from the other species of Ash native to the State. Flourishes best in the cooler portions of its range. Seldom thrives on dry ground. IMPORTANCE OF THE SPECIES — This species has probably never been grown for forestry purposes. It may be so recommended where natural reproduction may be depended upon and in such locations where other more valuable trees will not grow. Few better species grow in its chosen home and consequently it may be one which we will plant in the future in extremely wet locations together with others such as Spruce, Fir, and Larch. 216 RED ASH. Fraxinus pennsylvanica, Marshall. FORM — Tree of middle or large size, usually attaining a height of 30-60 ft. with a diameter of 1-3 ft., but may reach a height of 70 ft. with a diameter of 5 feet. Trunk similar to that of White Ash, but smaller and bearing numerous upright branches which form -a rather irregular and compact crown. BARK — Grayish-browu, roughened by numerous fissures separating prominent ridges which in time become scaly. Fissures usually diamond-shaped. Ridges often sub-divided by transverse secondary fissures. TWIGS — Similar to those of the White Ash but not so stout and covered with a dense velvety pubescence, or sometimes almost smooth. See "Twigs" under White Ash, page 214. BUDS — Opposite; terminal bufl present; ovate, brown, covered by brownish scales, 2 pairs of which are usually visible. Scales of the lateral buds usually have an obtuse apex while those of the terminal buds have a more acute apex. See "Buds" under White Ash, page 214. LEAVES — Opposite, compound, about 11 inches long, with 5-9 stalked leaflets. Leaflets from 3-5 inches long, 1-1J inches wide, ovate, acute at apex, slightly toothed on margin, wedge- shaped at base. At first coated on the lower surface with white tomentum, later becoming yellowish-green above, and decidedly velvety-pubescent beneath. LEAF-SCARS — Opposite; semi-circular in outline, conspicuous, slightly notched on the upper margin; bundle-scars numerous, usually small, and arranged in a curved line. Sometimes a number of bundle-scars unite to form a compound bundle-scar. FLOWERS — Appear about May before or with the leaves. Staminate and pistillate are usually borne on different trees. Stamina te occur in dense purplish-red clusters; pistillate in open greenish-red panicles. ^ FRUIT — A samara, borne in open panicles which often persist far into winter. The individual samara varies in length from 1-2 inches, and consists of a seed bearing portion and a winged portion. Fruit resembles that of the White Ash, but has the wmged portion attached not only to the apex of the seed but also along the sides, while the White Ash has the wing attached at the apex only. WOOD — Ring-porous; heavy, hard, rather strong, light brown, with rather wide and light colored sapwood. Pores in the spring and summer wood are similar to those of the White Ash, but the lines of pores in the summer wood are longer than in the White Ash. Weighs 44.35 Ibs. per cubic foot. Used for the same purposes as the White Ash, but is somewhat in- ferior to it from a commercial point of view. DISTINGUISHING CHARACTERISTICS— The Red Ash can be distinguished at any season of the year from the other species of Ash native to Pennsylvania by its velvety-pubescent twigs and. petioles. In addition it can be distinguished from the White Ash by its fruit, the wings of which are attached to the apex and the sides of the seeds, while those of the White Ash are at- tached at the apex only. The leaflets of the Red Ash are decidedly stalked while those of the Black Ash are sessile. The buds of the Red Ash are brown in color and usually obtuse, while those of the Black Ash are black in color and usually acute. The bark of the Red Ash is prominently-fissured while that of the Black Ash is not fissured but decidedly scaly and presents somewhat of a corky appearance. RANGE — Vermont west to Minnesota and southward to Florida and Texas. DISTRIBUTION IN PENNSYLVANIA — Found in the eastern and southern parts of the State. Not known to occur in other parts. HABITAT — Prefers rich soil In valleys; also found in swampy lowlands and along the margins of streams, lakes, and ponds; occasionally found upon rather dry hillsides. IMPORTANCE OF THE SPECIES — The Red Ash in many respects resembles the White Ash, but It Is of less economic importance since it does not attain so large a size as the White Ash, its wood is not quite so valuable, and it requires a somewhat moister soil. The White Ash will grow in all places where the Red Ash thrives, and consequently the White Ash should be favored. It is sometimes planted for ornamental purposes but the White Ash is generally regarded more attractive and just as free from the attacks of insects and fungi. The only place where the Red Ash could be recommended for planting for forestry purposes would be in such situations where it is too wet for the White Ash to thrive. PLATE CXXVI. RED ASH. 1. Branch with staminate flowers, x J. 2. A panicle of pistillate flowers, x J. 3. A mature compound leaf, x J. 4. A cluster of fruit, x i. 5. A winter twig, x J. 6. Section of a winter twig, enlarged. PLATE CXXVII. FRINGE-TREE. 1. A flowering branch with immature leaves, x J 2. A fruiting branch with mature leaves, x J. 3. A winter twig, x J. 4. Section of a winter twig, natural size. 217 FRINGE-TREE. Chionanthus virginica, Linnaeus. GENUS DESCRIPTION — The genus to which the Fringe-tree belongs has only one other rep- resentative. Both species are cultivated primarily for ornamental purposes. The generic name of these trees, Chionanthus, refers to the white flowers which resemble snow. FORM — A slender, small-sized tree usually attaining a height of 20 ft. with a diameter of 6-8 inches, but may reach a height of 40 ft. with a diameter of 12 inches. Trunk usually short, bearing numerous, stout, and ascending branches which form a rather deep, narrow crown. BARK — On main trunk rather thin, scaly, reddish-brown; on branches light brown to orange, and smooth. TWIGS — Rather stout, light brown tinged with green, somewhat angled, slightly hairy. Marked by large, conspicuous and elevated leaf-scars and dark colored lenticels. BUDS — Opposite, ovoid, sharp-pointed, about i of an inch long, covered with about 5 pairs of scales which increase in length from the outer surface and ciliated on the margin. LEAVES — Simple, opposite, thickish, ovate, 4-8 inches long, 1-4 inches wide, wedge-shaped at base, entire on margin, acute at apex, dark green above, pale and smooth below except along the veins. LEAF-SCARS — Opposite, raised, semi-circular in outline, upper side of margin partly surrounds bud; bundle-scars solitary, large, located on cushions. FLOWERS — Appear in May or June when leaves are just developing. Borne in drooping panicles about 4-6 inches long; perfect, white, and slightly fragrant. The appearance of the snow white flowers resembles fringe, hence the common name Fringe-tree. FRUIT — A berry, borne in loose clusters. Dark blue in color, about i-1 of an inch long, and surrounded at the base by a persistent calyx. Stalks bearing the fruit may bear leaf-like bracts. Skin of fruit usually thick and stones usually thin. WOOD — Light brown in color, with rather wide and lighter colored sapwood; heavy, hard, close-grained. Weighs about 40 Ibs. per cubic foot. It is put to no special commercial uses. DISTINGUISHING CHARACTERISTICS— The Fringe-tree, also known as Old Man's Beard, White Fringe, American Fringe, Flowering Ash, and Snow Flower tree, is native to only a few counties in the southern part of the State. This limited distribution, together with its small size and its simple, opposite, entire-margined and thick leaves will enable one to dis- tinguish it quite readily during the summer. The white fringe-like panicles of flowers will also assist during a limited portion of early summer. In winter, the opposite, rather stout branches bearing sharp-pointed, opposite buds covered with more than 4 pairs of scales, are also charac- teristic. The berry-like fruit combined with the opposite branching will distinguish this tree from practically all others found in the State. RANGE — Southern New Jersey and southeastern Pennsylvania to Florida and Texas. It is essentially a southern species. DISTRIBUTION IN PENNSYLVANIA— This tree is found locally in about 6 counties in the southeastern part of the State. It is nowhere abundant, nor does it attain any large dimensions. HABITAT — Usually found in rich, moist soil; also frequents banks of streams, lakes and swamps. IMPORTANCE OF THE SPECIES— The Fringe-tree is planted extensively for ornamental purposes as far north as Massachusetts. Its beautiful flowers and its attractive form recommend it for planting in lawns and parks. The main objectionable feature is the fact that it retains its foliage for a relatively short period during the summer, since the leaves are late to appear and early to disappear. The poor quality and small size of the wood which it produces, to- gether with its limited distribution and selective situations, do not recommend it for forestry purposes. It can readily be grafted upon our common species of Ashes. This enables one to develop it upon situations somewhat dry for the tree itself. 218 SWEET VIBURNUM. Viburnum Lentago, Linnaeus. FAMILY AND GENUS DESCRIPTION— The Honeysuckle family, Caprifoliaceae, is rather widely distributed in temperate regions. It comprises about 10 genera with 275 species of shrubs, trees, vines, and a few perennial herbs. About 8 genera are native to North America and 7 to Pennsylvania. The 7 genera native to this State comprise about 31 species, most of which are shrubs. The principal native genera are: The Elderberries (Sambucus), the Viburnums (Viburnum), the Bush Honeysuckles (Diervilla), the Honeysuckles (Lonicera) and the Snowberries (Symphoricarpos). Since most of the representatives of these genera are shrubs only a few have been discussed in this publication. A description of the others may be found in Gray's New Manual of Botany, or Porter's Flora of Pennsylvania. The Elders, belonging to the genus Sambucus, are among our best known shrubs. The Common Elderberry (Sambucus canadensis L.) is probably the best known. The flowers are conspicuous and sometimes jised in making wine. The fruit is eaten and also made into wine, pies, and jellies. The Honeysuckles (Lonicera) are very common in our gardens and parks as ornamental shrubs and vines. They comprise about 100 species of which number at least 10 species are native to Pennsylvania. The Viburnums (Viburnum) also comprise about 100 species of which number about 20 species are native to North America and 11 to Pennsylvania. All of our species are usually shrubs, rarely small trees. The two species described on the following pages are occasionally found as small trees. FORM — A shrub or small tree usually attaining a height of 10-15 ft., but may reach a height of 30 ft. with a diameter of 10 inches. Trunk usually short, bearing a round-topped crown formed by slender and usually drooping branches. BARK — Disagreeable in odor, reddish, roughened in older specimens by division and subdivision into thick plates which are scaly on the surface. TWIGS — At first greenish and covered with rusty hairs, later reddish to orange and rather smooth. BUDS — Opposite, long, slender, scurfy, reddish-brown, covered by two rather rough scales. Lateral buds are usually leaf-buds and closely appressed to twigs. Terminal buds are often flower buds with a marked swelling at the base, and about | of an inch long. LEAVES — Opposite, simple, ovate, about 2* inches long, sharp-pointed, narrowed or rounded at base, closely and very sharply serrate on margin, bright green, smooth on both upper and lower surfaces. Veins conspicuously connected by veinlets. Petioles often winged and grooved. LEAF-SCARS — Opposite, wide, broadly U-shaped, not encircling twigs, and usually with 3 bundle-scars. FLOWERS — Small, perfect, white, appearing in May or June in dense, many-flowered, sessile, terminal cymes which are usually 3-5 inches broad. FRUIT— A black or dark blue fleshy, sweet, rather juicy drupe, containing a flat oval stone, and grouped into small clusters borne on slender, reddish, and often drooping stalks. WOOD — Diffuse-porous; heavy, hard, dense, yellowish-brown, with very disagreeable and per sistent odor. Weighs 45.51 Ibs. per cubic foot. Not important commercially. DISTINGUISHING CHARACTERISTICS— The Sweet Viburnum, also known as Sheepberry, Nannybery, and Wild Raisin, resembles the Black Haw more closely than any other of our native Viburnums. It can be distinguished from the latter by its leaf-blades with acuminate apexes, its long-pointed buds, and its winged petioles. The Black Haw has leaf-blades with obtuse or merely acute apexes, short-pointed buds, and no winged leaf-petioles. The small lateral branches of the Black Haw are often stiff and stand out almost at right angles to the main axis, while those of the Sweet Viburnum are flexible and more erect. RANGE — Quebec to Manitoba, south to Georgia, Indiana and Missouri. DISTRIBUTION IN PENNSYLVANIA— Common in the eastern, southern, and central parts of the State; local in the western part, and less frequent in the northern part. HABITAT — Usually found along or near banks of streams and borders of lakes located in or near wooded areas. IMPORTANCE OF THE SPECIES — The Sweet Viburnum has no commercial value, so far as wood production is concerned. Its form, flowers, fruit, and foilage make it one of the most attractive of our small ornamental trees. PLATE CXXVIII. SWEET VIBURNUM. 1. A twig showing the opening of a terminal bud, x J. 2. A branchlet. with leaves and two cymes of flowers, x J. 3. A braiK-hlet with leaves and two clusters of fruit, x J. 4. A winter twig with lateral leaf-buds and terminal flower buds, natural size. 5. A leaf-scar with three bundle-scars, enlarged. PLATE CXXIX. BLACK HAW. 1. A branchlet with leaves and two cymes of flowers, x J. 2. A branchlet with leaves and two clusters of fruit, x J. 3. A winter twig with a large terminal flower bud and three leaf-buds. Two leaf-buds are op- posite, and located about the middle of the twig, while the third is at the base and to the right of the terminal flower bud, natural size. 219 BLACK HAW. Viburnum prunifolium, Linnaeus. FORM — A shrub or small tree usually attaining a height of 15 ft., but may reach a height of 35 ft. with a diameter of 10-12 inches. Trunk short, often crooked, bearing a rather broad and round-topped crown formed by stiff lateral branches. BARK — About 2/5 of an inch thick, reddish-brown, rough, broken into thick plate-like scales. TWIGS— At first reddish and smooth, then green, and later, during first winter, spine-like, gray tinged with red, and often covered with thin film-like bloom. Usually marked with orange-colored ienticels. BUDS — Opposite, \-$ of an inch long, covered with 2 rusty pubescent scales which enlarge into leaf-like bodies in spring when growth begins. Axillary buds I of an inch long, flattened, closely appressed to twig. Flower buds swollen near base. LEAVES — Opposite, simple, oval, 1-3 inches long, obtuse or slightly pointed at apex, usually wedge-shaped at base, finely serrate, on margin, , sometimes leathery when old, dark green above and pale green below; petioles usually round, rarely winged. LEAF-SCARS — See "Leaf -scars" under Sweet Viburnum. FLOWERS — Small, perfect, white, appearing about May in dense, many-flowered, sessile, and terminal cymes which are -3-4 inches broad. FRUIT — Fleshy, dark Wue drupe which is persistent, sweet and rather juicy; contains a flat oval stone; grouped in few-fruited clusters borne on reddish stalks. WOOD — See "Wood" ,under Sweet Viburnum. DISTINGUISHING CHARACTERISTICS— The Black Haw, also known as Sweet Haw, Sheep- berry, Stag-bush, and Nanny-berry, closely resembles the Sweet Viburnum. See "Distinguishing Characteristics" under Sweet Viburnum. The Black Haw and the Sweet Viburnum may further be distinguished from the Maple-leaved Viburnum (Viburnum acerifolium) by the palmate vena- tion of the leaf-blade and the small gaping buds of the latter, and from the Arrowwood (Viburnum dentatum) by the coarsely dentate leaves, the small gaping buds, and the evidently- stalked flower clusters of the latter. RANGE — Connecticut, south to Georgia, and west to Arkansas. DISTRIBUTION IN PENNSYLVANIA— Common in the eastern and southern parts of the State, and local to sparse in the other parts. HABITAT — Prefers dry rocky hillsides. Sometimes found in rather moist locations. Fre- quent along fences and roadsides where seeds may have been dropped by birds. Often forms almost impenetrable thickets along fences, especially when coppiced. IMPORTANCE OF THE SPECIES — It is of no commercial importance as a wood-producing tree, but for ornamental purposes deserves to be planted extensively. The bark of the roots is valuable medicinally. 220 GLOSSARY. Abortion. Imperfect development or non-development of an organ. Abortive. That which Is brought forth prematurely; coming to naught before it is completed. Achene. A small, hard, dry, 1-celled, 1-seeded fruit which does not open by valves. Acrid. Sharp or biting to the taste. Acuminate. Decidedly tapering at the end. Acute. Tapering at the end. Aesthetic. Pertaining to the beautiful. Afforesting. Turning ground into forest after being without a forest for a considerable length of time. Alluvial. Relating to the deposits of sand, clay, or gravel made by river action. Alternate. Not opposite to each other, but scattered singly along the axis. Ament, A peculiar, scaly, unisexual spike. Anther. The enlarged terminal part of a stamen which bears the pollen. Apex. The tip or end of a bud or leaf, i. e. the part opposite the base. Apical. Pertaining to the tip, end, or apex. Appresscd. Lying tight or close against. Arborescent. Tree-like in appearance, size, and growth. Aromatic. Fragrant ; with a pleasing odor. Astringent. Contracting; drawing together; binding. Axil. The upper angle formed by a leaf or branch with the stem. Axillary. Situate in an axil. Axis. The central line of an organ; a stem. Bark. The outer covering of a trunk or branch. Basal. Pertaining to or situated at base. Berry. A fruit which is fleshy or pulpy throughout. Bisexual. Having both stamens and pistils, i. e. male and female organs. Bloom. A powdery or somewhat waxy substance easily rubbed off. Bole. The body or stem of a tree. Boreal. Pertaining to the north. Bract. A modified leaf subtending a flower or belonging to an inflorescence. Bud-scales. Modified leaves covering a bud. Bundle-scars. Scars on the surface of a leaf -scar. Severed ends of the flbro-vascular bundle which connected the twigs with the leaves. Calyx. The outer portion of a flower, usually green in color. Cambial. Pertaining to the cambium. Cambium. A thin-walled formative tissue between the bark and wood. Capsule. A dry fruit composed of more than one carpel and splitting open at maturity. Carpel. A simple pistil or one member of a compound pistil. Oatkin. An ament or spike of unisexual flowers. Chambered. Said of the pith when interrupted by hollow spaces at rather regular intervals. Ciliate. Fringed with hairs on the margin. Coherent. Sticking together ; connected. Collateral. Accessory buds at the sides of axillary buds. Complete. Said of flowers when all parts are present. Compound, Composed of two or more similar parts united in a whole. Concentric. Said of growth rings when the growth center coincides with the geometrical center. Confluent. Flowing together ; uniting. Said of the bundle-scars when the separate ones flow together and appear as one. Conical. Cone-shaped. Conifers. A group of trees which usually produce their fruit in the form of a cone. Coniferous. Cone-bearing. Conniving. Brought close together. Contorted. Twisted together or back upon itself. Convergent. Tending to one point. Cordate. Heart-shaped. Corolla. The inner portion of perianth, composed of petals. The bright colored part of most flowers. Corymb. A flat-topped or convex flower cluster, blooming first at the edges. Corrugated. Shaped into grooves, folds, or wrinkles. Crown. The upper mass of branches, also known as head. Cyme. A flower cluster blooming from apex or middle first, usually somewhat flat. Cymose. In a cyme; cyme-like. Deciduous. Falling -off, usually at the close of the season. Decurrent. Extending down the stem below the insertion. Defoliation. Removal of foliage. Dehiscent. Splitting open. Deliquescent. Said of the form of a tree with a broad spreading habit. The branches subdivide until they apparently disappear. Deltoid. Delta-like, triangular. Dentate, Toothed, usually with the teeth directed outwards. Diffuse-porous. Equal-pored. Said of wood when pores in a growth ring are equal in size. 221 Dig Hotels-compound. With the members arising at the same point at the end or top of the support. Dioecious. Unisexual, with the two kinds of flowf.rs on different plants. Disseminated. Scattered; thrown broadcast. Divergent. Pointing away; extending out. Said oi buds which point away from the twigs. Downy. Covered with fine hairs. Drupe. A fleshy fruit with a pit or stone. Eccentric. Not circular. Said of growth rings when growth center does not coincide with geometrical center. Elongated. Long drawn out. Embryo. A young plant in a seed. Entire-margined. Margin smooth, not cut or roughened. Epidermis. The outer layer or covering of plants. Equidistant. Equal distances apart. Even-pinnate. With all the leaflets occurring in pairs. Excurrent. Said of a tree with a continuous trunk and erect habit of growth. Exfoliation. Splitting or cleaving off of outer layers of bark. Exotic. Of foreign origin. Exudation. Oozing out of sap, resin, or milk. Fascicle, A cluster, usually dense. Fertilisation. The process by which pollen stimulates the ovule to produce a seed. Fetid. Ill-smelling. Fibro-vascular bundles. The conducting strands which connect the leaves with the stem. Fibrcnis. Consisting of fibers; woven in texture. Filament. The stalk bearing the anther. Fissures. Grooves, furrows, or channels as in the bark. Flora. The complete system of plants found in a given area. Fluted. Grooved, corrugated, channeled. Follicles. A dry fruit of one carpel, splitting on one side only. Forestry. The rational treatment of woodlands for their products. Fruit. A developing or ripened ovary. It may also include the axis containing the real fruit. Funtjus. A plant devoid of green color such as mushrooms and rots. Gaping. With an open slit at the end or apex. Genus. A group of related species, as the pines or the oaks. Glabrous, Smooth, without hairs. Glandular, Bearing glands or gland-like. Glaucous. Covered with a bluish or whitish waxy coating ; a bloom. Globose. Ball-like or nearly so. Globular. Ball-like. Habitat. The home of a plant. Head. A dense cluster of sessile flowers or the crown of a tree. Heartwood. The dead, central, usually highly colored portion of the trunk. Herbaceous. Herb-like, soft. Heterogeneous. Composed of dissimilar elements, as the wood of the hardwoods. Homogeneous. Composed of closely resembling elements, as the wood of the conifers. Imbricated. Overlapping like the slate on a roof. Incomplete. Said of flowers in which one of the outer parts is wanting. Increment. Growth ; increase. Indehiscent. Applied to fruits that do not split open to let out the seeds. Indigenous. Applied to plants that are native to a certain locality. Inflorescence. The flowering part of a plant, and especially its arrangement. Intolerant. Not shade enduring. Requiring sunlight. Involucre. A circle of bracts surrounding a flower or cluster of flowers. Irregular. Said of flowers showing inequality in the size, form, or union of similar parts. Keeled. With a central ridge, like the keel of a boat. Lamina. The blade or flattened portion of a leaf. Lanceolate. Shaped like a lance ; several times longer than wide. Lateral. Situated on the side, as the buds along the side of the twig. Leaflets. One of the small blades or divisions of a compound leaf. Leaf-scars. The scar left, by the falling of a leaf. Lenticels. A corky growth on young or sometimes older bark which admits air to the interior of the twig or branch. Linear. Line-like, long and narrow, with parallel edges. Lobed. Said of leaves that have the margins more or less cut or divided. Lunate. Of the nhape of a half-moon or crescent. Manna. A sweetish secretion used in medicine as a mild laxative. Medullary, Pertaining to the pith or medulla. Medullary Ray. Radial lines of tissues crossing the growth rings at right angles and extending into the bark. Midrib. The central or main rib or vein of a leaf. Mongrel. Composed of two elements of entirely different origin. Monoecious. Bearing stamens and pistils in separate flowers on the same plant. Morphological, Pertaining to the form and structure of plants. Mucilaginous. Shiny, or gummy when chewed. Naked. Said of Luds without scales and seeds without a covering. Naval Stores. Refers to tar, turpentine, resin, etc. 222 Nerve. One of the lines or veins running through a leaf. Node, A place on a twig where one or more leaves originate. Non-porous. Without pores. Nut. A dry, 1-seeded, iiidehiscent fruit with a hard covering. Nutlet. A small nut. Ob-. A prefix meaning inverted or reversed. Oblique. Slanting, uneven. Oblong. About twice as long as wide, the sides nearly parallel. Obovatc. Reversed egg-shaped. Obtuse. Blunt. Odd-pinnate. With an odd or unpaired leaflet at the tip of the compound leaf. Opposite. Said of leaves and buds, directly across from each other. Orbicular. Circular. Ovary. The part of the pistil producing the seed. Ovate. Egg-shaped. Ovoid. Egg-shaped or nearly so. Ovule. The body which after fertilization becomes the seed. Palmate. Hand-shaped; radiately divided. Panicle. A compound flower cluster, the lower branches of which are longest and bloom first. Parasite. Growing upon and obtaining its nourishment from some other plant. Parenchyma. A class of plant tissue found in the green layers of the bark, in wood and pith. Pedicel. The stalk of a single flower. Peduncle. The stalk of a flower cluster or of a solitary flower. Pendulous. Hanging. Perennial. Last for more than onp year. Perfect. A flower with both stamens and pistils. Perianth. A term applied to the calyx and corolla taken together. Persistent. Remaining after blooming, fruiting, or maturing. Petals. The part of a corolla, usually colored. Petiole. The stalk of a leaf.. Pinna. A division, part, or leaflet of a pinnate leaf. Pinnate. With leaflets On both sides of a stalk. Pistil. The central part of the flower containing the prospective seed. Pistillate. Bearing pistils but no stamens. Pith. The soft central part of a twig. Pod. Any dry and dehiscent fruit. Pollen, The dust-like substance found in the anthers of a flower. Pollination. The process of bringing the pollen of the male flower in contact with the stigma of the female flower. Polygamous. With both perfect and imperfect, staminate or pistillate, flowers. Pome, A fleshy fruit with a core, such as the apple. Prickle. A sharp-pointed, needle-like outgrowth. Profligate. Wasteful, extravagant. Propagative. Said of buds containing reproductive organs. Pseudo-l A prefix meaning false, not true. Pubescent, Hairy. Pungent. Ending in a sharp point; acrid. Pyramidal. Shaped like a pyramid with the broadest part near the base. Raceme. A simple inflorescence of flowers borne on pedicels of equal length and arranged on a common, elongated axis. Ray. See Medullary ray. Reflexed. Abruptly turned backward or downward. Reforestation. The process of putting a forest growth upon an area which had its forest growth removed recently. Regular. Said of flowers which are uniform in shape or structure. Resin-ducts, A passage for the conduction of resiu found in the leaves and wood of the Pines. Ring-porous. Said of wood which has pores of unequal size, the larger ones being found in the spring wood and the smaller in the summer wood. Rugose. Wrinkled. Rugosities. Projections, wrinkles, knobs. Saccharine. Pertaining to or having the qualities of sugar. Samara. An indehiscent winged fruit. Sapwood, The recently formed, usually light wood, lying outside of the heartwood. Scales. The small, modified leaves which protects the growing-point of a bud or the part of a cone which bears the seeds. The small flakes into which the outer bark of a tree divides. Scurfy. Covered with small bran-like scales. Sepal. One of the parts of the calyx. Serrate. Having sharp teeth pointing forward. Sessile, Seated; without a stalk. Sheath, A tubular envelope or covering. Shrub. A low woody growth which usually branches near the base. Silky. Covered with soft, straight, fine hairs. Simple, Consisting of one part, not compound. Sinus. The cleft or opening between two lobes. Species. A group of like individuals as Red Oak, White Oak, etc. Spike. An enlongated axis bearing sessile flowers. 223 Spile. A small peg or wooden pin. Sometimes synonymous with pile. Spine. A sharp woody outgrowth. Stamen. The part of a flower which bears the pollen. Staminate. Said of flowers which bear only stamens. Sometimes spoken of as male. Sterigmata. The projections from twigs bearing leaves. Sterile. Barren ; unproductive. Stigma. The end of a pistil through which pollination takes place. Stipule. A leaf-appendage at the base of the leaf-stalk. Stipule-scar. The scar left by the fall of the stipule. Stoma. An opening in the epidermis of a leaf communicating with the internal air cavities. Striote. Marked with fine elongated ridges or lines. Striations. Long narrow lines or ridges. Strobile, A fruit marked by overlapping scales as in the Pine, Birches, etc. Style. The pin-like portion of the pistil bearing the stigma. Sub-. A prefix meaning under or nearly. Sucker. A shoot arising from an underground bud. Superposed. Said of buds when they are arranged one above the other. Symmetrical. Regular as to the number of parts. Having the same number of parts in each circle. Terminal. Pertaining to buds located at the end of twigs. Thorn. A stiff, woody, sharp-pointed projection. Tolerant. Applied to trees which endure certain factors, particularly shade. Tomentum. A dense layer of hairs. Tomentose. Densely pubescent; hairy. Truncate. Ending abruptly, as if cut off at the end. Tubercle, A small tuber or tuber-like body. Tufted. Growing in clusters. Umbel. A flower-cluster with all the pedicels arising from the same point. Unisexual. Consisting of one sex only, either staminate or pistillate. Valvate. Said of buds in which the scales merely meet without overlapping. Vegetative. Said of buds which do not contain reproductive organs. Veins. Threads of fibro-vascular tissue in leaves or other organs. Versatile. Used for many purposes. Viscid, Glutinous ; sticky. Whorl. A group of three or more similar organs, as leaves or buds, arranged about the same place of attachment. Whorled. Borne in a whorj. Xylology. The science which treats of the form and structure of wood. (224) INDEX. Page. Abies balsamea, 84 Abies Fraseri, 84 Acacia, 181 Three-thorned, 179 Acer, 190 Negundo, 197 pennsylvanicum , 192 platanoides, 198 Pseudo-platanus , 198 rubrum, 55, 56, 196 saccharinum , 195 saccharum 61, 194 spicatum, 193 Aceraceae, 190 Aesculus : glabra, 200 octandra, 201 Hippocastanum, 200 Ailanthus, 38, 187 glandulosa, 187 Alder, 38, 47, 48 Black, 39, 121 Smooth, 121 Alders, 45 Alnus rugosa, 121 Alternate-leaved Dogwood, 205 Amelanchier canadensis, 174 Anacardiaceae, 182 Angelica Tree, 199 Anonaceae, 160 Apple, American Crab, 172 Aralia spinosa, 199 Arbor Vitae, 41, 86 Arrow-wood, 219 Ash, :..... 22, 23, 47, 212 Basket, 215 Biltmore, 213 Black, 215 Brown, 215 Canadian , 214 Green, 213 Hoop, 215 Mountain, .' 48, 173 Page. Red, 216 White, 214 Ash-leaved Maple, 197 Asimina triloba, 160 Aspen, 38, 94 American, 96 Large-toothed, 97 Quaking, 96 Small-toothed, 96 Trembling, 96 Balm of Gilead, 94 Balsam, 84 Basswood, 35, 38, 44, 48, 202 White, 203 Beaked Hazelnut, 122 Beaked Willow, 93 Bear Oak, 144 Bebb's Willow, 93 Beech, 30, 35, 39, 45, 49, 123, 125 American , 12Ji Blue, 120 European , 125 Water, .- 120 Beech family, 124 Bee-tree, 202 Benzoin aestivale, 161 Betula, 112 alba var. papyrifera, 114 lenta, 118 lutea, 115 nigra, 116 populifolia, 117 Big Tree of Tule, 32 Big Trees, 33 Bignoniaceae, 211 Bignonia family, 211 Bilsted, 163 Birch: Black, 118 Oanoe, 114 Cherry, 118 Gray, 115, 117 Oldfield, 117 15 (225) 226 Page. Paper, 36, 57, 114 Poplar, 117 Poverty, 117 Red, 116 River, 57, 116 Silver, 115 Sweet, . 118 Yellow, 115 Birch family, Ill Birches, 30,31,38,44,45,47,48,112 Bladder Nut, 49 Bow-wood, 153 Box Elder, 197 Boxwood, 204 Buckeye: Big, 201 Fetid, 57, 200 Ohio, 200 Stinking, 200 Sweet, 57, 201 Yellow, 201 Buckeyes, • — 41 Butternut, 38, 102 Buttonball, 175 Buttonwood, 31,34,35,39,47,175 Calico-bush, 207 Canoe Birch, 114 Caprifoliaceae, 218 Carolina Poplar, 99 Carpinus caroliniana , »....*. 120 Carya, ... 104 alba, 108 cordiformis, .................. 110 glabra, ,.,..,,,,,,«».. 109 illinoensis, , .. v«nviiit*tt«*: 105 laciniosa, .,< «*««.<*««<*< «i«i 107 microcarpa > ................... 105 ovata, .....><»,..».***>i«i»,,..,,>,*»,, ,t?;.20j 57, 87 White, ........... ..,,^..36, 57, 85 Page. Celtis: crassifolia, 152 occidentalis, 152 Cercis canadensis, 180 Chamaecyparis thyoides, 85 Cherry : Appalachian, 165 Bird, 168 Black, 166 Cabinet, 166 Choke, 167 Domestic, 165 Fire, 168 Perfumed, 165 Pin, 168 Rum, 166 Sand, 165 Sour, 165 Sweet, 165 Wild, 166 Wild Black, 45, 166 Wild Red, 168 Chestnut, . .- 20,23,27,30,31,33,38,40, . 45,46,47,57,125,126 Chinquapin, 33, 127 Chionanthus virginica, 217 Cigar Tree, 211 Coffee Nut, 178 Coffee- tree, Kentucky, 178 Colorado Blue Spruce, > 79 ornaceae, 204 Cornel, Flowering, 204 Cornus: alternifolia, 205 florida, ,... 204 Corylus: americana, 122 rostrata, i .;..<»«. i*« 122 Cotton Tree, ,..,.., 99 Cottonwood, .;.94, 99 Black, ....t;:;^;. 98 River, .....»;<.; ..;*>; 98 Swamp, ;;.... 98 Crab Apple, American, .;«:.,.,.:. 172 Crack Willow, ....;;..*....*...... 89 Grata egus: coccinea, .......... :..<:.. •...'. 171 Orus-galli, ui.i.iii.Uiiiiiiu 170 Cucumber Tree, .;<<;.......;<;.;.,. 157 Custard Apple family, .>........,: 160 Cypress, Bald, 30 227 Page. Date-plum, 210 Deerwood, 119 Diospyros virginiana, 210 Dogwood, 44, 204 Alternate-leaved , 205 Blue, 205 Flowering, 204 Purple, 205 Ebenaceae, 210 Ebony family, 210 Elder, 38 Elderberry, Common, 218 Elkwood, 158 Elm, 38 American , 151 English, 149 Ofay, 151 Moose, 150 Red, 150 Slippery, 150 Water, 151 White, 151 Elms, 46, 47, 149 Ericaceae, 207 Evergreen Oaks, 128 Fagaceae, 124 Fagus: grandifolia, 123 sylvatica, 125 Filbert, 122 Fir, Balsam, 35, 84 Fire Cherry, 168 Firs, 31, 55 Fraxinus, 212 americana, 55, 214 Biltmoreana , 213 excelsior, 212 nigra, 215 ornus, 212 pennsylvanica var. lanceolata, 213 Pennsylvania , 216 Fringe Tree, 217 Gleditsia triacanthos, 179 Great Laurel , 208 Gum: Black, 33,36,38,206 Red, 163 Sour, 206, 209 Sweet, 35, 163 Gymnocladus dioica, 178 Hackbejry, 35,38,47,152 Hackmatack , 77 Hack-tree, 152 Page. Hamamelidaceae, 162 Hamamelis virginiana, 162 Haven-wood, 187 Haw, 170 Black, 219 Sweet, 219 Hawthorn, 170, 171 Scarlet, 171 Hazelnut, 45 American, 122 Beaked, 122 Common, 47 Heath family, 207 Hedge-tree, 153 Hemlock, 31,33,35,36,50,51,57,83 Ca rolioa, 83 Ground , 67 Spruce, 83 Hercules' Club, 199 Hickory: Big Bud, 108 Big Shell-bark, 107 Bitter, 110 Bitter Nut, 110 Brotfm, 109 Mocker Nut, 108 Pecan, 105 Pignut, 109 Shag-bark, 36, 106, 107 SbeU-bark, 106 Small-fruited, 105 Swamp, 110 . White-heart, . . 108 Holly: American, 31, 188 Deciduous, 31 European, 188 Large-leaved, 18t) Mountain, 189 White, 188 Honey Locust, 38, 179 Honey Shucks, 179 Honeysuckle family, 218 Hop Hornbeam, American, ..44,45,49,119 Hornbeam, American, 120 Horse-chestnut, 200 Ilex: aquif olium , 188 monticola , 189 opaca, 188 verticillata , 189 Indian Bean, 211 Ironwood, 119, 120 228 Judas Tree, Juglans, cinerea, nigra, regia, .. Page. . 180 101 . 102 . 103 101 Juglandaceae, 100 June Berry, 174 Juniper: Common, 41,87 Dwarf, .07 Red, 87 Juniperus: communis, 87 virginiana, ' 87 Kalmia latifolia, 207 Kentucky Coffee-tree, 38, 41, 178 Larch, 30, 50, 55 American, • 67, 77 Black, 77 European, ' 77 Larix: laricina, 77 decidua, ,77 Lauraceae, , 101 Laurel: Great, 208 Mountain , '. 31, 207 Laurel family, 161 Laurel Magnolia, 31, 57, 156 Leguminosae, 176 Leverwood , 119 Lime-tree, 202 Linden , 202 White, 203 Linden family, 202 Liquidambar, 163 styraciflua, ... 163 Liriodendron Tulipifera, 159 Live Oaks, 128 Locust: Black, 181 Common, 41,42,45,48,181 Honey, 38, 179 Sweet, 179 White, 181 Yellow, 181 Lombardy Poplar, 33, 94 Lynn, 202 Madura pomif era , 153 Magnolia, 38,41,44,57,155 acuminata, 157 Laurel, 31,57,156 Smnll, 156 Page. tripetala, 158 virginiana , 57, 156 Magnoliaceae, 155 Magnolia family, 155 Mahogany, 178 Maple: Ash-leaved, 197 Hard, 194 Mountain, 38,57,193 Norway, 198 Red, 38,56,57,196 River, 195 Rock, : 194 Silver, 195 Soft, 195, 196 Striped, 38,39,45,192 Sugar, 38,60,61,194 Swamp, .. 196 Sycamore, »... 198 White, 195,196 Maple family, 190 Michaux Basswood, 202 Moosewood, • 192 Morus : ,alba, 154 •rubra, 154 Mulberry, 45, 47 Black, 154 Red,. 154 White, 154 Nannyberry, 218, 219 Nettle family, ..-. 47, 148 Nettle-tree, 152 Nicker Tree, 178 Ninebark, 164 Nyssa sylvatica, 206 Oak: Barren, 145 Bear, 56, 144 Black, 35, 142 Black Jack, 145 Bur, 134 Chestnut, 137 Chinquapin, 136, 138 Dwarf Chinqun pin , 138 Ground, 144 Iron, 133 Jack, 145, 146 Laurel, 146 Mossy-cup, 134 Over-cup, .• 134 Peach, 147 Pin, 33,34,35,140,147 229 Page. Post, 133 Red, 33,56,139 Rock, 40, 137 Scarlet, 141 Scrub, 33,56,144 Scrub Chestnut, 138 Shingle, 146 Spanish , 143 Swamp, 140, 147 Swamp White, 135 Water, 140,146,147 White, 33,57,132 Willow, 147 Yellow, 136, 142 Oilnut, 102 Old Man's Beard, 217 Olea Europaea, 212 Oleaceae, 212 Olive family, ' 212 Olive Tree, 212 Osage Apple-tree, 153 Osage Orange, 47, 153 Osier, Green, 205 Ostrya virginiana, 119 Oxydendrum .arboreuni , 209 Papaw, 38,41,45,47,160 Paradise Tree, 187 Peach, 165 I'epperidge, 206 Persimmon, 50, 210 Physocarpus opulifolius, 164 Picea, 78 Abies, 79, 82 mariana, 81 pimgens, 79 rubra, 80 Pigeon-berry, 205 Pinaceae, 55, 67 Pine: Austrian , 68 Jack, 55, 71 Jersey or Scrub, 33,57,75 Nigger, 55, 71 Norway, 72 Pitch, 20,55,71 Poverty, 73 Red, 22,55,57,72 Scotch, 68, 76 Pine: Short-leaf, 74 Table Mountain, 57,73 White, 20,22,31,32,33,48,55,70 Yellow, 57, 74 Page. Pine family, 55, 67 Pinus: echinata , 74 laricio var. austriaca, 68 pungens, 73 resinosa, 55, 72 rigida, 55, 71 Strobus, 55, 70 sylvestris, 68, 76 virginiana, 75 Plane Tree, 175 Plane Tree family, 175 P.latanaceae, 175 Platanus: occidentalis, 175 orientalis, 175 Plum: Porter's, 165, 169 Red, 169 Wild, 169 Wild Yellow, 169 Poison: Dogwood, 184 Elder, 184 Ivy, 182 Oak, 182,184 Sumach, 184 Poplar, 94,96,97 Balsam, 94 Birch, 117 Carolina, 99 Downy, 98 L/ombajdy, 33, 94 Silver-leaf, 94 Swamp, 98 White, 94 Yellow, 159 Popple, 96,97,159 Populus, 94 alba, 94 balsamif era , 94 candicans, 94 deltoides, 99 grandidentata , 97 heterophylla , 98 nigra var . italica , 94 tremuloides, 96 Prunus, 165 alleghaniensis, 165 americana, 169 avium , 165 Cerasus, 165 cuneata , 165 230 Page. Mahaleb, 165 pennsylvanica , 168 Persica, 165 pumila, 165 serotina, 166 virginiana, 167 Pulse family, 47, 176 Pussy Willow, 92 Pyrus: americana, 173 coronaria, 172 Quaking Aspen, 96 Quassia family, 187 Quercus, 128 alba, 55, 132 bicolor, 135 coccinea, 141 falcata, 143 ilicifolia, 56, 144 imbricaria, 146 macrocarpa, 134 marylandica, 145 Muhlenbergii, 136 nana, 66 palustris, : 140 phellos, 147 prinoides, 138 Prinus, 137 pumila, 56 rubra, 56, 139 stellata, 133 velutina, 142 Redbud, .%. 180 Rhododendron, 31, 208 maximum, 208 Rhus: canadensis, 182 copallina, 186 Cotinus, 182 glabra, 182 Toxicodendron, 182 typhina, 185 Vernix, 184 Robinia Pseudo-Acacia, 181 Rosaceae, 164 Rose Bay, 208 Rose family, ; 164 Salicaceae, 88 Salix, 89 babylonica, : 89 discolor, 92 fragilis, 89 lucida, ., 91 Page. nigra, 90 rostrata , 93 Sambucus canadensis, 218 Sapindaceae, 200 Sarvice, 174 Sassafrac, 161 Sassafras, 38,50,161 variifolium, 161 Savin, 87 Saxifrax, 161 Sequoia, 32, 33 Service Berry, 174 Shad Bush, 38,48,174 Sheepberry, 218,219 Simarubaceae, 187 Slippery Elm, . .. 150 Smoke Tree, 182 Soapberry family, 200 Sorrel Tree, 209 Sour Gum, 206,209 Sour-wood, 209 Spanish Oak, 143 Spice Bush, -. 161 Spruce, .31,36,50,55,78 Black, 81 Colorado Blue, 79 European, ... 82 Norway, 22,79,82 Pine, 80, 83 Red, 80 Stag-bush, 219 Sugarberry, 152 Sumach, 38, 48 Dwarf, 186 Fragrant, 182 Mountain, 186 Poison, 184 Smooth, 182, 185 Staghorn, 185 Swamp, 184 Velvet, 185 Sycamore, 175 Tamarack, 77 Taxaceae, 67 Taxus canadensis 67 Thorn Apple, 170 Newcastle, , 170 Scarlet, 171 Tree, : . : 179 Thuja occidentalis, 86 231 Page. Tilia: americana, 202 heterophylla, 203 Michauxii, 202 Tiliaceae, 202 Tree of Heaven, 187 Tsuga: canadensis, 83 caroliniana , 83 Tulip Poplar, 159 Tulip Tree, 31,33,34,38,44,45,159 Tupelo, 206 Ulmus, 149 americana , 151 campestris, 149 fulva, 150 Umbrella Tree, 158 Urticaceae, 148 Viburnum: dentatum, 219 Lentago, 218 Maple-leaved, 219 prunifolium, 219 Sweet, 218 Page. Walnut, 22,38,44,45,101,103 Black, 38,43,103 English, 101 White, 102 Walnut family, 100 Whistle-wood, 192 Whitewood, 159,202 Willow, 31,45,46,47,89 Beaked, 93 Bebb's, 93 Black, 90 Crack, 89 Glaucous, 92 Glossy, 91 Oak, 147 Pussy, 92 Shining, 91 Weeping, 33, 89 Willow family, 88 Winterberry, 189 Witch-hazel, 45,48,162 Yellow-wood, 153 Yew, American, 67 (232) Pamphlets Ponnsylvs P4P3 . 301953 UNIVERSITY OF CALIFORNIA LIBRARY