eo ee SaaS Sees ET . Se Rew VDork State College of Agriculture At Cornell Aniversitp Ithaca, 42. DV. Library Forestry in Minnesota. Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www. archive.org/details/cu31924003019563 FORESTRY IN MINNESOTA. BY SAMUEL B. GREEN, PROFESSOR OF HORTICULTURE AND FORESTRY, "THE UNIVERSITY OF MINNESOTA. PUBLISHED BY THE GEOLOGICAL AND NATURAL HISTORY SURVEY OF MINNESOTA. PREFACE TO FIRST EDITION. This book has been prepared especially for the classes in forestry in the School of Agriculture of the University of Min- nesota. It is really a compilation of the lectures and mimeo- graphed notes that I have found useful in my experience in teaching the elementary principles of forestry. The word for- estry is here used in the broad sense in which it is often used in this section and includes much that, strictly speaking, would come under several allied heads. In the use of botanical names I have followed, so far as possible, those given by Dr. George B. Sudworth in his “Nomenclature of the Arborescent Flora of the United States,” which has been adopted as the standard for the Agricultural Colleges and Experiment Stations. Oth- erwise the Index Kewensis has been followed. But where these names are different from those commonly used by horti- culturists in current literature the more familiar term is also generally given in brackets. I have received many kind suggestions and criticisms from Dr. Otto Lugger, St. Anthony Park; Hon. L. R. Moyer, Mon- tevideo; and Messrs. John §. Harris, La Crescent; Clarence Wedge, Albert Lea; F. H. Nutter, Minneapolis, and J. M. Underwood, Lake City. Professor Conway McMillan has fur- nished many specimens for drawings. My assistant, Mr. W. A. Wheeler, has given much carerul attention to the revi- sion of the manuscript and has corrected many errors that would otherwise have crept in. I am especially indebted to all these parties who have aided me in this work, and I wish to extend my sincere thanks for their interest and kindness. In the preparation of this book I have freely consulted the “Silva of North America” (Prof. C. S. Sargent); “Illustrated 4 PREFACE TO FIRST EDITION. Flora of the United States” (Britton & Brown); the publica- tions of the Division of Forestry of the Department of Agri- culture; “Baume und Striucher des Waldes” (Hempel & Wil- helm); and Flora von Deutschland, Oesterreich u. d. Schweiz (Prof. Dr. Thome). S. B. G. University of Minnesota, St. Anthony Park, July 20, 1808. PREFACE TO SECOND EDITION. The first edition of 10,000 copies of “Forestry in Minne- sota’ was published by the Minnesota Forestry Association and has been received with much favor. It is now probably used in more than fourteen of the agricultural colleges as their chief text book on this important subject and it is also used in a number of normal and high schools in this and other states, either as a text book or as supplementary reading. The first edition is practically exhausted, but the demand for it continues to increase, and it is this demand, and the fact that it concerns a subject closely related to the development of this state, which has induced the Board of Regents to publish it as a portion of the report of the Geological and Natural History Survey of Minnesota. This edition covers all the ground reached by the first edi- tion, but it has been improved by the better classification and extension of the matter in Part I, and some additions and cor- rections to Part II. I think it greatly improved for the pur- poses of a text book, for which it is primarily intended. Since the publication of the first edition the world of science and especially the state of Minnesota have lost two helpful men in the death of Dr. Otto Lugger and J. S. Harris, each of whom assisted in preparing the first edition of “Forestry in Minnesota.” To me this is a personal bereavement, and I extend to their wives and children my most heartfelt sympathy and best wishes. In this revision I have had the loyal and painstaking help of my assistant, Mr. T. L. Duncan, and the chapter on Forest Mensuration has been almost entirely prepared by him. The drawings, with few exceptions, have been made under my direction by Miss M. M. Cheney. The half tone illustra- tions are mostly from photographs taken in the division of Horticulture and Forestry. Figure 32 is from a photograph 6 PREFACE TO SECOND EDITION. loaned by Professor John Gifford, Figure 9 is from H. B. Ayres, Figure 32 from W. H. Rau. By permission of Houghton, Mif- flin & Co. the typical botanical figures of plates 14, 15, 21, 22, 23, 24, 26, 31, 35, 43, 45, 49, 55 and 63 have been redrawn from the “Silva of North America.” The typical botanical figures of plates 1, 6, 7, 10, 20 and 25 are redrawn from “Baume und Straucher des Waldes.’’ Plate 52 is redrawn from Flora von Deutschland, Oesterreich u. d. Schweiz. SAMUEL B. GREEN. January 30, 1902. Chapter I. Chapter IT. Chapter ITT. Chapter IV. Chapter V. Chapter VI. Chapter VII. Chapter VIII. Chapter IX. Chapter X. Chapter XI. Chapter XIT. Chapter XIII. Chapter XIV. Pinacee. Pines, Larches, Spruces, Hemlock, Douglas Spruce, CONTENTS. PART I. ELEMENTARY FORESTRY. The Tree. The Forest. Forest Influences. Tree Planting on Prairies. Forest Regencration and Treatment. Propagation. Nursery Practice. Forest Protection. Rate of Increase. Forest Mensuration. Forest Problems in Minnesota. Wood and its Uses. Durability of Wood. Forest Economics. PART II. TREES OF MINNESOTA. Pine Family. Arborvitz and Junipers. Juglandacce. Walnut Family. Walnut, Butternut and Hickories. Salicacee. Willow Family. Willows and Poplars. Betulacce. Birch Family. Birches, Alders, Hornbeam and Blue Beech. Fagacce. Oak Family. Chestnut and Oaks. Firs, 8 CONTENTS. Ulmacee. Elin Family. Elms and Hackberry. Moracee. Mulberry Family. Mulberries. Rosacee. Rose Family. Wild Crab. Mountain Ashes, Serviceberries, Thorns, Flum and Wild Cherries. Leguminose. Pea Family. Honey Locust, Coffeetree and Locust. Aceracee. Maple Family. Maples and Boxelder. Hippocastanacce. Buckeye Family. Horse Chestnut and Ohio Buckeye. Rhamnacee. Buckthorn Family. Buckthorn. Tiliacee. Linden Family. Basswoods. Elacagnacce. Olcaster Family. Russian Olive. Oleacee. Olive Family. Ashes. Bignoniacce. Bignonia Family. Catalpa. Caprifoliacee. Honeysuckle Family. Sheepberry. PART III. FOREST TREES OF THE UNITED STATES. GLOSSARY. INDEX, Wild PART I. ELEMENTARY FORESTRY. CHAPTER I. THE TREE. A tree is a woody plant with a single stem more or less branched and taking on what is commonly known as the form. tree The most evident parts of a tree are roots, stem or trunk, branches, buds, leaves, flowers, fruit and seed. The Stem, Branches and Roots are made up of inner bark, outer bark, sapwood and heartwood. Cross-section of Woody Figure 1. Stem —diagram showing (a) outer bark, (4) inner bark or bast, (c) cam- bium, (d,¢, f,g and /) annual rings of wood, and (2) pith. The outer bark, sap- wood and_ heartwood are made up of concentric circles termed annual rings. During each period of growth two new rings are formed—one on the outside of the sapwood and another on the inside of the outer bark and as we sel- dom have more than one sea- son of growth each year but formed on the one ring is wood in a year; so that by counting the rings of wood in the stem we can determine very closely the age of trees. In very rare cases we have two periods of growth in one year, as in 1894, when the drouth of midsummer ripened up the wood of the trees by the first of August and the rainsof autumn started a new growth, and caused some trees and shrubs to Hower in October, but such occurrences are very uncommon and the extra rings formed 12 ELEMENTARY FORESTRY. are readily detected by their being smaller than adjoining rings and less distinctly defined. The age of trees could be told by the rings of the outer bark nearly as well as by those of the wood were it not for the fact that the outer layers of bark fall off as the tree grows older. In some experiments the bark of rapidly growing branches was peeled back in the spring for a few inches, the wood cov- ered with tin-foil and the bark replaced. At the end of the sea- son there was found a ring of wood outside of the tin-foil, thus showing where the annual growth of the tree was made. The Bark covers the whole exterior surface of the trunk, branches and roots and serves as a protection. It is made up of two parts, the outer or corky layer which is dead bark and the inner or live bark. These vary much in appearance and thickness on different kinds of trees. For instance, on the White Birch the corky layer is pure white, very thin and tough, while on our White Pine it is very dark brown and often an inch or more in thickness and quite brittle. The Sapwood is the portion of the wood next to the bark. It varies much in thickness in different species and in trees of the same species; the most rapidly grown trees contain the largest amount. It is the most active portion of the wood in the growing tree, and contains considerable plant food and more water than the heartwood. The Heartwood is the wood in the center of the trunk and is generally distinguished from the sapwood by its more com- pact structure and darker color, though in some cases it may be lighter colored than the sapwood. It is also harder and more valuable for fuel, shrinks less in drying, and is more dura- ble in contact with the soil than the sapwood. There is very little movement of the sap in the heartwood. The Roots furnish water and nourishment that the plant receives from the soil, but only the young roots have the power of taking up the soil water; the older roots are most useful in holding the tree in place. It is common to classify roots into surface roots and tap roots, depending on their shape and the depth they go in the ground. Some trees have nearly all surface roots, as the Birch and Spruce, others have nearly all tap roots, which often go to a great depth on dry land, as those of the Bur THE TREE. 13 Oak, White Oak, Black Walnut and Butternut. Most of our trees have a combination of the two kinds, as the Maple, Hack- berry and Ash. Seedling trees of most kinds have a decided tap root when young, but in many species it ceases to grow down ward when a few years old. This is true of the Red and Scarlet Oaks, which often have a tap root extending four feet in depth Figure 2. Characteristic Root Formation. On the left two Hackberry, on the right two White Birch, each 2-year seedlings from same seed bed. “The first with a divided tap root, the second without tap root. before the tree has attained a corresponding height above ground, but after about five years large lateral roots develop and the growth of the tap root nearly ceases. Root growth is relatively less to the extent of ground occu- pied in moist and fertile soil than in dry and poor soil, but the roots are proportionately more branched. In wet seasons the root development is less for a given plant than in dry seasons, because the roots may get their needed food and water from a small area. Nursery trees grown on moist rich land have a more compact root system than those grown on poor land. At the Minnesota Experiment Station a small Bur Oak growing on dry, gravelly soil had a tap root that was evidently 20 feet long, while on moist fertile clay land in the same section such trees probably seldom have tap roots more than six feet long. Buds are placed regularly on the young branches and are 14 ELEMENTARY FORESTRY. said to be cither alternate or opposite. When they occur on the stump or on roots they are not arranged in any regular order. There are two kinds of buds—flower buds, which develop into flowers and fruit; and leaf buds, which develop into leaves and branches. These can generally be @4istinguished from each other by their shape and size and by cutting through them and noting their construction. Flower buds are generally more lia- ble to injury from climatic changes than leaf buds. The Leaves of our trees vary much in size and shape. They are simple when composed of but one piece, as the leaves of the Oak, Maple and Birch, and compound when composed of more than one piece, as the leaves of the Locust, Ash and Black Walnut. Leaves are made up of a framework filled in with cellular tissue and covered with a thin skin. This skin has very many small pores in it called stomata, through which the plant takes in carbon dioxide from the air and gives off oxygen and water. All our trees shed at least a part of their leaves each year. All the broad-leaved trees and the Tamarack shed their entire foliage yearly, while our so-called evergreen trees lose a part of their leaves each year. The length of time leaves remain on this latter class of trees varies from two or three years, in the case of White Pine growing in very severe locations in this section, to perhaps eight years, in the case of Red Cedar favora- bly located. The time that leaves remain on the branches of evergreens depends to some extent on the location and age of the individual tree. The following table gives the approximate length of time that leaves of conifers remain on trees in Minnesota: THE TREE. 15 LENGTH OF TIME THAT LEAVES OF CONIFERS REMAIN ON TREES IN MINNESOTA. Botanical Name. Common Name. Year of Falling. PINUS SLVOBUS . oie vee eevee eee | White Pine sii... 2204 2d and 3d. PURWS Pl@RLUS 4 se suean sree de evnaes Western White Pine.| sth and 6th. PIBUS VESINOSA! a sicissnde Ho eies S00 ones Norway Pine........ 4th and sth. Pinus Qtvar1eala aa cicaveae Gh ene4 59 | Jack: Pine: oo: sseiunede 2d and ad. Pinus ponderosa scopulorum ...... | Bull Pineas vecesccnane 3d and 4th. PINUS SYLUESUITS. ie o's a sie ts BGS | Scotch Pine .......... | 3d. Pinus lartcto austriacd...... 0.4.5. Austrian Pine........ 4th and sth. Pinus montana pumtla.... 0.0.0... Dwarf Pine occ. eke sth, 6th and 7th. LOX AVCHD seve sain nioens 24 vse ne | Tamarack esses 00 vi 1st winter. EGVLE CUROPER Leased. gikus bos ....| European Larch.....) rst winter. Picea canadensts .................. | White Spruce ..... 4th and sth. PICEA MAKIANA 20. Levee ee eee Black Spruce......... 4th and sth. LACED. DUNGEONS: siccden Reokuain iayend Blue Spruce.......... 6th and 7th. Picea ENGEIMAUNE Cove e cc cceccceee. Engelmann Spruce ..| 5th and 6th. BECCA CEMCOVSA, 5.2 visa ens it eee pe esti Norway Spruce .. -| 5th. TSUfa CORAMENSIS sscc000 sc. 000r | Memlock: 2.2.0 22260: 2d and 3d. Pseudotsuga taxtfolia....... 6.000. | Douglas Spruce...... 5th. ALOIES GOS HEED Rese ievislra eine eehaetiae | Balsam Fir ove! Sth. AO eSHEOMCOTON a, dhud acreg otis eed | Wihlites BID 2. cin cae ae sth. THUZA. OCCTMENLAMS 3.025 03.5 eS Arborvite ...........| 4th and sth. SUNTPEVUS VIF EINTANA .... 0s | Red Cedar............ 5th and 6th. SUNTPCYUS COMMUNIS coe veee cere | Dwarf Juniper....... sth and 6th. Flowers are parts of the plant especially modified for the reproduction of the plant by seed. Both sexual organs may be located together in the same flower, as those of the Bass- wood, Mountain Ash and Cherry; or in separate flowers on the same plant, as those of the Birch, Oak and Black Walnut; or they may be separate on entirely different plants, as in the Willow, Poplar, Boxelder and Ash. 16 ELEMENTARY FORESTRY. The Fruit, botanically defined, is the seed-containing area, derived from a single flower. As used in nursery practice the term is generally applied to seeds having a fleshy covering or an adjoining fleshy part. The Seed, botanically defined, is the ripened ovule, but as the term is used in nursery practice it often includes the ovary and other parts that may be attached to it. What is commonly called the seed of Maple, Ash, Elm, Walnut and Basswood is really the fruit. Distribution of Seeds. The seeds of plants are distributed in various ways, the most common of which are (1) by means of floats or wings which buoy the seeds up in the air or water, and (2) by animals. The seeds of Ash, Arborvite, Boxelder, Catalpa, Elm, Maple, Pine and Spruce have wings which allow them to be blown great distances by the wind, especially when they break loose from the upper branches of high trees during severe winds. The seeds of the Honey Locust are not shed from the pod until after it has fallen, and as the pod is ten inches or more long and spirally twisted it may be blown long distances on level ground or snow crust. The seeds of the pop- lars and willows have a cottony float attachment which buoys them up in the air. In the case of the Basswood, the parachute- like bract attached to the seed cluster aids in spreading the seeds by carrying them through the air or along the snow crust. The seeds of Mountain Ash, Wild Black Cherry, Hawthorn and oth- ers are largely distributed by wild animals which eat the fruit and allow the seeds to pass through the alimentary canal unin- jured or carry off the fruit and spit out the seeds. Many seeds or seed vessels have bur-like or sticky coats by which they adhere to animals and are thus carried considerable distances. Very often bodies of water aid in the distribution of seeds, since all that are spread by the agency of the wind and most of those that have fleshy coverings will float on the surface of the water and may in this way be scattered. Shapes of Trees. Different species of trees naturally develop different shapes. Some, like Spruces, Tamarack and Balsam, have a decided tendency to form a strong stem and to take on a conical form in preference to the development of a crown or head; while others, like the Basswood, Oaks, Maples and Boxelder, develop their crown in preference to their stem. THE TREE. 17 The actual shape of trees depends on the space they have to grow in, on the soil, situation, and on the age of the trees. Where trees have plenty of room to grow, and their natural development is not interfered with, their individual character- istics are most apparent. TREE GROWTH. Assimilation. Plants are made up of various tissues and these are formed of numerous cells. The material of which the cells are composed is largely carbon. This carbon is derived irom the carbon dioxide of the air which enters into the leaves and under the action of light, air and water is there decom- posed; the oxygen is given off and the carbon is retained, and, combined with water obtained from the roots, forms starch, sugar, gum and other plant foods. This process of food making is called assimilation and can be carried on only in the green parts of the plant, and in these only when exposed to light and air. Hence, foliage, air and light at the top are essential prerequisites for tree growth, and, other conditions being favorable, the greater quantity and bet- ter development of foliage and the more light this foliage has at its disposal for its work, the more vigorously will the tree grow. In general, therefore, the growth of wood may be reduced either by the removal of foliage, which reduces the working surface, or by shading, which somewhat checks the activity of the fohage by hindering hght action. Transpiration. The flow of sap in trees is not well under- stood. Ina general way it may be said that the sapwood trans- mits the water irom the roots to the leaves, where a part enters into the assimilated sap and goes to build up the plant, and the remainder, which is by far the greater part, passes off as vapor. The amount thus transpired varies greatly with the species, age of the tree, amount of foliage at work, amount of light at its disposal. climatic conditions and the condition of tree growth The amount of water transpired is so large in comparison to the amount retained in the tree that while an acre of forest may store in its frees 1,0co pounds of carbon, 15 or 20 pounds of mineral substances and 5.cco pounds of water in a year, it may 5) a 1s ELEMENTARY FORESTRY. have taken from the soil and given off to the air from 500,000 to 1,500,000 pounds of water, or from one-quarter to one-half as much as agricultural crops. It has been estimated that the leaves of deciduous trees transpire one-sixth to one-third as much water as an equal surface of water. Large deciduous trees undoubtedly give off as much as a barrel of water a day in dry summer weather. Coniferous trees transpire much less water than most deciduous trees, frequently not over one-sixth as much. Mineral Substances are taken up in small quantities and consist mostly of lime, magnesia and potash. They are carried to the leaves, where they are used (pei:haps also on their passage through the tree), with a part of the water, in food preparation. The main part of the mineral substances taken up remains as the water transpires in the leaves and young twigs, and is returned to the soil when the leaves are shed, and when the tree is cut and the brush leit to decompose and make humus. - The Soil of Woodlands is Improved from year to year if the leaves and litter are allowed to remain on the ground and fire is kept out, since the mineral matters taken up by the tree are largely returned to the soil in a more soluble form and the amount of humus is increased. For this reason there is little need of alternating woodland crops. Almost any soil can furnish a sufficient quantity of mineral substances for the production of a crop of trees, provided it is moist and the leaf mould is not removed. Good soils will con- tinue to furnish mineral matter in sufficient quantity, even if a portion of the leaf mould is carried away. If, however, this removal is continued annually for a long period, any but exceed- ingly fertile soils are likely to become exhausted, just as land on which field crops are grown cannot produce crops forever without manuring. The Yearly Round of Life in a Tree. In the spring the tree starts into growth and feeds on the plant food stored up the preceding year; the leaves unfold and commence furnishing plant food. These two sources of food push the growth along very rapidly in the spring and carly summer. By the first of July the food stored up the previous season is exhausted in many trees, and growth is entirely dependent upon the food fur- TREE GROWTH. 19 nished by the leaves. The growth at this time is gencrally much slower than in the spring, and as the capacity of the tree for building up plant food increases it commences to store up starch, sugar and other foods in its cells with which to start growth the following spring, and the cell walls become thicker and firmer. This maturing of the tree is termed the ripening of the wood, and when completed the tree is ready for winter. Our hardiest trees generally ripen their wood early in the autumn and then cease growing, although probably some food is being stored up so long as the leaves remain green on the trees. Rest Period of Plants. With very few exceptions all plants require an occasional rest period for their best development. Some species get it naturally by being dried and others by being frozen. And even when plants are kept under growing condi- tions the year round they have periods of rest and of excite- ment. During the rest period the plants undergo very few changes, and yet there is undoubtedly some growth during mild weather in winter, and, as evaporation must be going on most of the time from twigs and buds. water must be supplied from the roots. The Amount of Water Lost by Trees in Winter. Aiter many careful experiments, A. L. Knisely, M. 5., concludes that a Soft Maple standing 30 or 35 feet high with a trunk 15 to 18 inches in diameter near the ground, exposing from 750 to 800 square feet of bark surface, may lose daily by evaporation from 6 to 7 pounds of water when dormant. An apple tree 30 years old and 15 inches in diameter at the base, exposing from 800 to 1,000 square feet of bark surface, may lose daily while dormant from 10 to 13 pounds of water. These figures are from results obtained during winter weather in New York, where the relative humidity of the air is higher than in Minnesota, which would lessen evaporation. It is probable that during our winters here the evaporation from trees will greatly exceed that in New York, and that greater evaporation is nearly always responsible for some trees being tender here and hardy in New York and other places with similar conditions. ‘ We know that in this section after a prolonged period of severely cold weather, the twigs of Soft Maple, Apple and some 20 ELEMENTARY FORESTRY. other trees have a decidedly shrivelled appearance, which disap- pears after a few days of mild weather. Soft Maple trees stand- ing on dry land will sometimes in the spring appear to have been dried out and to have become partly or entirely dead. It is probable that during our coldest weather very little, if any, moisture can be suppl'ed from the roots, which may account for this shrivelled condition. Second Growth. Sometimes warm, moist weather in late autumn will cause trees to start a strong second growth in October, which draws on the stored plant food and perhaps exhausts it, and winter sets in before the tissues have again become hard and stored with food. In such cases trees are liable to injury. No characteristic of hardiness is more impor- tant in plants than that of early maturity of wood. One part of the tree may start into growth without regard to the conditions of the other parts. For instance, a branch brought into a warm room in winter without severing it from the tree will grow for some time. Sun seald is probably due to the bark on the side most exposed to the sun starting into growth very early, after which a sudden freeze destroys the young cellular tissue. CHAPTER II. THE FOREST. Forest is a Term variously applied in this country. As here used it applies to all collections of trees except such as are grown for fruit. It may, then, apply to a picce of land on which seedlings have only recently been planted, or to what is termed brush land, or to land heavily stocked with trees. TREE GROWTH AFFECTED BY LIGHT CONDITIONS. So Important is Sunlight to the Growth of Trees that it is sometimes said to be the purpose of trees to convert sunlight into wood. Practically all trees make their most rapid growth in full sunlight There is, however, quite a difference in the power of various trees to get along with small amounts of direct sunlight. It is the object of good forestry to grow as much good timber as possible upon the land, just as good agriculture consists in growing the largest amount of farm crops upon the land. An acre of land covered with trees of the same species, it is estimated, will lay on the same amount of woody fibre whether the stems are large or small, the amount of wood formed each year being in direct ratio to the amount of foliage covering the land that is in good active condition. It is known that some trees will do very well in the shade of other trees. This gives a chance to grow trees in a sort of two-storied fashion, having the land nearly covered with the foliage of one set of trees which require the full exposure to sunlight, and underneath the land covered with the foliage of trees which will endure the shade of those above them, just as pumpkins can be grown under corn. On account of this peculiarity of trees, foresters have divided them into two classes, one of which is called light demanding and the 22 ELEMENTARY FORESTRY. other shade enduring. ‘The words tolerant and _ intol- erant are also used as distinguishing the peculiarity of trees in this respect, and they are perhaps better terms. Trees that are known as tolerant generally have a thicker mass of foliage than those that are intolerant of shade. ‘This simply means that their lower leaves can withstand the shade of their upper leaves. While it is not an absolute rule that tolerant species have a thick mass of foliage and intolerant trees open foliage, yet it is so generally true that where the characteristics of a tree are known it serves as a very reliable indication. Most trees are much more tolerant of shade when young than when old. Among our tolerant trees may be mentioned the Spruce, Oak, Balsam, White Cedar, Red Cedar, Hornbeam and Hard Maple. Among our intolerant species are Poplars, Cotton- wood, Willows, Soft Maple and Birch. Of our native pines, the White Pine is much more tolerant than either the Jack or the Norway Pine, which are quite intolerant of shade and soon succumb if they are protected from the full sunlight. Trees Protect One Another and are Mutually Helpful, and many trees that are quite hardy on the limits of their growth when grown in groups, will fail if grown singly, as for instance the Hard Maple in exposed parts of Minnesota. Trees also interfere with one another and struggle for light and soil conditions, and the weaker trees are destroyed. So true is this that where the land is thickly seeded with even-aged trees, they may all become weak and sickly because of hindering one another. On the other hand, this crowding of trees forces them to take on an upward growth and kills out the lower branches. Trees growing under such conditions make long timber free from knots, which is therefore most valuable. SOIL CONDITIONS. Water Supply. Water is the most important element in soils for tree growth, and the greatest attention must be given to its conservation and distribution through the soil. Trees do not grow to best advantage in very wet or in very dry soil, although some can live and almost thrive under Ritch euntaverds ble conditions. There is very little land, except in the arid SOIL CONDITIONS. 23 region, but that will support some form of tree growth. The soil best adapted to all kinds of trees is one that is moderately but evenly moist, porous, deep and well drained; yet with a subsoil compact enough to transmit the subsoil water from below upwards without its being so solid that it cannot be easily penetrated by the roots. It does not matter about its being stony if it has these qualities. On land that is very wet in this section, as the muskegs of northern Minnesota, which are covered with Tamarack and Spruce, the trees never get to be of large size. In the case of one Spruce grown on such land, 73 years was occupied in growing a tree 1% inches in diameter, and a Tamarack under similar conditions formed a diameter of only 1 1-10 inches in 48 years. We also find that growth is extremely slow on very dry land. On very open porous land the water sinks quickly out of reach of the roots, and where the soil is too compact it cannot be penetrated by the water or by the roots, so that on such soils trees generally suffer for moisture a part of the year. Relation Between Trees and Soils. The growth of trees and the kinds growing on land are good though not infallible indexes to the value of the soil for agricultural purposes. For instance, land on which Black Walnut, Hard Maple, Hackberry or Hickory grow to large size is of good quality for grasses, grains and other agricultural crops, while Black Oak is gener- ally abundant on dry, gravelly ridges and sandy soil. Where White Pine in this section is the prevailing tree the land is gen- erally of good quality. Norway Pine will endure more drouth than the White Pine, outgrows it, and becomes the prevailing tree on drier land, while the Jack Pine is the most abundant on the very dry sandy lands of Northern Minnesota. In the more humid climate of the eastern states the White Pine grows on very sandy soils. Mechanical Condition of Land in Forests. The agri- culturist aims to keep the soil porous, yet moderately compact, that the roots may penetrate it easily and the subsoil waters may be readily transmitted upwards to the roots of plants. He aims to prevent the soil from becoming too compact and from the loss of water from evaporation by cultivating the surface soil, and to keep out standing water by drainage. The forest at ELEMENTARY FORESTRY. grower cannot rely upon such methods, because they are too expensive or entirely impracticable. He may indeed plow for his first planting and cultivate the young trees, but alter a few years cultivation will become impossible and the effects of the first preparation will be lost. He must therefore attain his object in another way, that is, by mulching the soil. The shading is done at first by planting very closely, so that the ground may be protected as soon as possible from sun and wind. The shade should be maintained well throughout the life of the tree, even if more planting is necessary to accomplish it, and if in later life the trees get thin in the tops or die out, it may become necessary to plant underbrush to protect the land. Undergrowth in Forests may be rather injurious in pre- venting the proper development of young trees, but it is gen- erally very beneficial in retarding evaporation from the surface soil, in retaining the snow in the spring and in killing out grass and weeds. Forest Floor is a term used to indicate the mulch on the eround in forests. This is made up of the fallen twigs and leaves which remain on the ground, where they slowly decay and form a cover of rich mould or humus. This protective covering serves a most useful purpose; it permits the rain and snow waters to penetrate the soil without at the same time mak- ing it too compact, thus keeping the soil granular so that the air can enter, and in the best condition for conducting water, while at the same time it prevents washing away of the land and too rapid or excessive evaporation from the surface; the humus is also an active agent in aiding decomposition of the mineral substances in the soil. Subsoil. Tree growth is less dependent on the condition of the surface soil and more dependent on the subsoil than is the growth of agricultural crops. For instance, in the case of drift- ing sand overlying a moist subsoil, it has been found that where pains are taken to get the young trees started they will often do well although such land is poorly adapted to agricultural crops. There are many acres of land in Minnesota and Wis- consin that have such conditions, and they should seldom be entirely cleared of trees. Washing of Soils. The soils most likely to wash badly SOIL CONDITIONS. 25 are those that are fine grained without much adhesive power, such as fine sand and some kinds of clays. When, however, such soils have a forest growth on them they are protected from washing by the forest floor, tree roots and the humus in the soil. Soil which contains large quantities of humus does not wash much, since the particles of organic matter bind it together; thus we find that newly-cleared timber land which contains large amounts of humus may not wash much for a number of years after the clearing, and then commence to wash very badly. The washing away then is due to the humus havy- ing become used up and there being nothing left to bind the soil particles together. In such cases the application of organic matter will help very materially. For this purpose manure, straw or other material may be applied, or crops like clover and the grasses, which leave considerable organic matter, may be grown on the land. Crops that leave very litthe humus in the ground, such as nursery stock, which is dug out by the roots, are most harmtul in exhausting the humus in the soil, and land used for this purpose needs heavy manuring with stable manure and an occasional seeding down to grass or clover. Alkali Soils. In the prairie portions and occasionally elsewhere in this section, we have a kind of soil in which there is a superabundance of carbonate and sulphate of soda. This kind of soil seldom extends over large areas and generally occurs in places lower than the surrounding land. In some places the alkali occurs in such abundance as to coat the surface of the soil with a white crust. On such land very few agricul- tural crops or trees grow well. The leaves of the trees growing there generally take on a yellowish color and the wood does not mature well in the autumn. Such land should be drained so that the surface water at least can run off. In this way the alkali can generally be washed out in a few years. It is seldom advisable to plant trees on these places, but if this seems desira- ble, as is sometimes the case on prairies, the best trees to plant are probably the Cottonwood and White Willow. 26 ELEMENTARY FORESTRY. EFFECT OF SLOPE AND ASPECT ON TREE GROWTH. The slope of the land affords drainage and so affects the growth oi trees, but trees will grow on any slope, even on precipices, if they can find room for their roots and the soil is somewhat moist. The direction of the slope usually has a very marked effect on the growth of vegetation. This is especially the case where high ranges of hills and other local conditions modify the climate. A Northern Slope receives no full sunlight; the sun’s rays fall obliquely in the morning or toward evening, according to the angle of elevation. The winds it receives in winter are colder than those received by the southern slope, but the few winds which strike it during the growing season are not strong, hot or very dry. As the vegetation is a little delayed on a northern slope, there is less danger from late spring frosts than on a sunnier aspect, and, as the snow melts slowly, there is a better chance for its waters to soak into the ground. In con- sequence of these facts trees are less liable to suffer from drouth on the same kind of Jand with a northern than with a southern exposure. The trees keep a more regular form and growth is more uniform and certain. It will generally be found that where timber is cut off from a northern slope growth renews itself very quickly, for tree seeds are most likely to grow undei the conditions found there. An Eastern Slope receives the sun in the cool morning hours when the temperature and light are moderate. It is not exposed to our hot, dry winds nor to the intense heat of the sun. The soil retains its moisture fairly well and trees make a eood growth. For trees it ranks next in value to a northern slope. A Southern Slope receives the most direct rays of the sun, and the full force of our hot, dry winds and beating rains during the growing season. Consequently vegetation is more liable to injury by late spring frosts, because of starting earlier in the spring, than in any other location. The soil is most liable to erosion from beating summer rains and dries up most quickly after the spring rains. The trees grow irregular in form, the seeds seldom start well on southern or western slopes, ASPECT. 27 and when once cleared tree growth is often difficult to renew As proof of the importance of these conditions as affecting tree growth we have the commonly observed fact that the south and west sides of steep hills and mountains are more likely to be bare than any others. This can be very plainly seen on the bluffs along the Mississippi River in Minnesota. A Western Slope receives the sun’s rays obliquely, but in the warmest part of the day, and in this section gets the full foree of our hot dry southwest winds. The effect of such an exposure on growth is about the same as the southern slope. CHAPTER III. FOREST INFLUENCES. Upen careful observation it will be found that a single large spreading tree growing in an open field appreciably affects climatic and soil conditions in the following ways: (1.) During the day the ground under a tree is protected from the sun's rays and is therefore cooler than soil not protected. As a result of this protection, the air under the tree is cooler than the air in the open, and, as it is constantly in circulation, tends to cool the air in the immediate vicinity of the tree on sunny days. (2.) At night a tree retards the radiation of heat from the ground under it. This tends to equalize the temperature of not only the soil and air under the tree, but that in the near vicinity. Therefore, though a tree may reduce the temperature of the soil and air on sunny days or during a short period of warm weather, it may, on the other hand, increase the temper- ature at night or during a short period of cool weather. For example it may be noticed that vegetables growing near trees are frequently uninjured by autumn frosts which destroy those growing in the open. (3.) A tree aids in retaining water in the surface soil to the leeward by breaking the force of the wind, and thus retarding evaporation, for it is known that evaporation increases with the rapidity of the air currents. It retains the water in the surface soil under the tree by shading the soil and thus retarding evap- oration. The large amount of water which is transpired by a tree is largely drawn from the subsoil, and this increases the humidity of the surrounding air without drawing on the water of the surface soil. But some kinds of trees take up so much of the water from the soil as to preclude the growing of crops in such places near them. FOREST INFLUENCES. 29 (4.) The leaves that fall to the ground form a mulch which pre- vents the drying out of the soil. They check the flow of water over the land, thus preventing the washing away or compacting of the soil by heavy rains, and giving the water a better chance to soak into the ground. (5.) A tree protects from the destructive force of severe winds. A single tree or group of trees may seem to have little effect on tornadoes, but large groups of trees may possibly prevent their formation or greatly lessen their violence. Protection from severe winds may greatly affect the growing of plants, since on account of the winds many plants that may be suc- cesstully grown when protected by shelter belts cannot be grown on the open prairie. This protection, when present, serves to lessen the fuel necessary to warm dwelling houses and also lessens the food eaten by animals. It also keeps the surface soil in fields from being blown away. In these five principal ways a single tree affects the condi- tions of climate and soil in its immediate vicinity. To be sure, some of them are not so very evident where a single tree grows in an open field, but where trees are growing in groups or on large tracts of land all of these factors are important in modily- ing climate and soil conditions, and will be referred to at greater length. INFLUENCE OF FORESTS ON WATER SUPPLIES. It is very evident that the proper disposition of water upon the land is the most important factor in the growing of crops, and it is equally evident that nature’s changeful and wasteful ways of supplying water to crops are not the best ways of so doing, for we know that not only in the arid regions, but in gen- eral wherever irrigation is used, crops are produced in greatest abundance and certainty. This once recognized, then the proper distribution of the available water supplies becomes a question of immediate interest. Human effort can, to a limited extent, direct the laws of nature that influence climate and soil condi- tions, and it becomes necessary that we have a clear understand- ing of the forces that are at work in nature in order that we may know where we may or may not expect to be successful in directing them. In order that we may better understand this 80 ELEMENTARY FORESTRY. subject, I quote the following extract on forest influences from the report of the Forestry Division of the U. S. Department of Agriculture for 1889, with a few changes in the nature of abbre- viations: “The water capital of the earth may be regarded as consist- ing of two parts, the fixed capital and the circulating capital. The first is represented not only in the waters on the earth but also by that amount of water which remains suspended in the atmosphere, being part of the original atmospheric water-masses which, after the rest had fallen to the cooled earth, remained in suspension and is never precipitated. “The circulating water capital is that part which is evap- orated from water surfaces, from the soil, from vegetation, and which, after having temporarily been held by the atmosphere in quantities locally varying according to the variations in tem- perature, is returned again to the earth by precipitation in the form of rain, snow and dew. There it is evaporated again, either immediately or after having percolated through the soil and been retained for a shorter or longer time before being returned to the surface, or, without such percolation, it runs through open channels to the rivers and seas, continually returning in part into the atmosphere by evaporation. Practically, then, the total amount of water capital remains constant; only one part of it—the circulating capital—changes in varying quantities its location, and is of interest to us more with reference to its local distribution and the channels by which it becomes available for human use and vegetation than with reference to its practically unchanged total quantity. “As to the amount of this circulating water capital we have no knowledge; hardly an approximate estimate of the amount circulating in any given locality is possible with our present means Of measurement; for it appears that so unevenly is the precipitation distributed that two rain gauges almost side by side will indicate varying amounts, and much of the moisture which is condensed and precipitated in dews escapes our obser- vation, or at least our measurements, entirely. Thus it occurs that while the amount of water calculated to be discharged annually by the river Rhone into the sea appears to correspond to a rainfall of 44 inches, the records give only a precipitation over its watershed of 27.6 inches. FORESTS AND WATER SUPPLY. 31 “We must therefore enter into our discussions acknowledg- ing ignorance of one of the most important factors, at least as to its numerical or quantitive value. “The distribution of the circulating water capital is influenced by various agencies. The main factor which sets the capital afloat is the sun, which, by its heat and the air currents caused by it, and by the rotation of the earth, produces the evaporation which fills the atmosphere with vapor. Anything, therefore, that influences the intensity of insolation, the action of the sun, or obstructs the passage of winds, must influence the local dis- tribution of the water capital. The great cosmic influences which produce the variability of all climatic conditions, and therefore also of the circulating water capital, are the position of the earth’s axis to the sun, by which the angle and therefore the heat value of the sun's rays vary in different parts of the earth and at different times of the year; the distribution of land and water areas, which produces a difference of insolation because the water has less heat capacity than the land, and which also influences the direction of air and sea currents; the configura- tion of the earth, by which the density of the atmosphere is made unequal, and in consequence of which differences of inso- lation and of air temperature are induced. Thus we have not only climatic zones, but also continental climates and mountain climates in opposition to coast climates and plain or valley cli- mates. “While this classification of cosmic climates satisfies the climatologist, there are many local climates to be found within the range of the cosmic, and the local climatic conditions are those which affect human life and human occupations most sen- sibly. “The same causes, different only in degree, which modily the cosmic climates, making a classification of the same possi- ble, effect further modifications and give rise to local climates; these causes are different in the degree of insolation, obstruction to air currents, presence of water surfaces, or moisture-laden, air strata. “Among the factors which thus modify the cosmic climate and help to produce a local climate differing from other local climates, the soil cover, and especially the presence of forest areas, is claimed as one that, under certain conditions, is potent: be ELEMENTARY FORESTRY. and this factor, being under the control of human agency more than any other possible modifier of climate, must therefore be of greatest interest to us. It is clear, from what has been stated so far, that the influences of the forest, if any, will be due mainly to its action as a cover protecting the soil and air against insola- tion and against winds. That the nature of a cover, its density, thickness, and its proper position has everything to do with the amount of protection it affords, everybody will admit. A mos- quito net is a cover, so is a linen sheet or a woolen blanket, yet the protection they afford is different in degree and may become practically none. It will also be conceded that it makes a great difference whether the cover be placed before or behind the wind. Just so with the influence of the forest; it makes all the difference whether we have to do with a deciduous or conifer- ous, a dense or an open, a young low or an old high growth, and what position it occupies with reference to other climatic elements, especially to prevailing winds and water surfaces. In the following discussions, when the word forest is used, unless differently stated, a dense growth of timber is meant. “The question of forest influences on water supplies can be considered under three heads, namely—influence upon precipi- tation or distribution of atmospheric water; influences upon conservation of available water supplies; influence upon the dis- tribution or ‘run-off’ of these supplies. INFLUENCE UPON PRECIPITATION. “Whether forest areas are, or are not, capable of appreciably increasing precipitation within their limits or on neighboring eround is still a matter of dispute, and the complexity of the elements which must enter into the discussion has so far baf- fled solution based upon definite and strictly scientific observa- tion. Yet new evidence is accumulating all the time which apparently shows that under certain conditions forest areas obtain larger precipitations than open grounds, that is, they may inerease at least the amount of precipitation over their own immediate and near lying areas. {In Minnesota popular opinion inclines to the belief that there is a close connection between the existence of forests and the rainfall of this section, and that with the disappearance of ELEMENTS OF DISSIPATION. 33 our forests will come a much more rigorous climate and a decrease in rainfall. But the records of the weather bureau do not show that there is any connection between the two or that there has been any apparent change in the general climate or amount of rainfall due to the removal of our forests. The flow of water in most of our rivers, and in many cases the flow of water from springs, and the height of the water table in the land, have been most seriously affected by the removal of our forests and should be regarded as the ways by which our water supply is to suffer most severely from deforestation. ] DISPOSAL OF WATER SUPPLIES. “Given a certain amount of precipitation in rain or snow over a certain area, the disposal of the water after it has fallen, and the influence of the forest cover on its disposal, require our attention. For the sake of convenience we can divide the ele- ments which need consideration in this discussion into elements of dissipation, elements of conservation, elements of distribu- tion. “The difference in effect between the first two classes of ele- ments will give us an idea of the amount of available water sup- ply or run-off resulting from precipitation, while the third class bears upon the methods of distributing the available water sup- ply. ELEMENTS OF DISSIPATION “Elements of dissipation are those which diminish the avail- able water supplies; they are represented in the quantity of water which is prevented by interception from reaching the ground, in the quantity dissipated by evaporation, in the quan- tity used by plants in their growth, and in that used by trans- piration during the process of growing. Interception. The amount of rainfall and snow which is prevented by a forest from reaching the soil varies considerably according to the nature of the precipitation and to the kind of trees which form the forest, as well as the density and age of the growth. “A light drizzling rain of short duration may be almost entirely intercepted by the foliage and at once returned to the atmosphere by evaporation; if, however, the rain continues, 3 3 ELEMENTARY FORESTRY. although fine, the water will run off at last from the foliage and along the trunks. : “Altogether for the rainfall conditions of Austria, Prussia and Switzerland, where measurements have been made, a dense forest growth will on the average intercept 23 per cent of the precipitation; but if allowance be made for the water running down the trunks, this loss is reduced to not more than 12 per cent. “The amount of interception in the open growths which characterize many of our western forest areas would be consid- erably smaller, especially as the rains usually fall with great force, and much of the precipitation is in the form of snow. Although branches and foliage catch a goodly amount of this, the winds usually shake it down, and consequently but very little snow is lost to the ground by interception of the foliage. “There is also a certain amount of water intercepted by the soil cover and held back by the soil itself, which must be sat- urated before any of it can run off or drain away. This amount, which is eventually dissipated by evaporation and transpiration, depends, of course, upon the nature of the soil and its cover. especially upon their capacity to absorb and retain water. “The water capacity of litter depends upon its nature and of course its thickness to a certain degree, but is much greater than that of soils. “Altogether an appreciable amount of the precipitation does not run off or drain through the forest cover, but is retained by it; yet, while this is apparently a loss, we shall see further on that this moisture retained in the upper strata fulfills an impor- tant office in checking a much greater loss due to evaporation, and thus become an element of conservation.” Evaporation. The loss by evaporation after the water has reached the ground depends in the first place upon the amount of direct insolation of the soil, and hence its temperature, which again influences the temperature of the air. The nature of the soil cover, the relative amount of moisture in the atmosphere and the circulation of the air are also factors determining the rate of evaporation. The importance of evaporation as an ele- ment of dissipation may be learned from the experiments of Prof. T. Russell, Jr., of the U. S. Signal Service, made in 1888. We learn from these that the evaporation on the western plains WIND-BREAKING POWER OF FORESTS. 35 and plateaus may, during the year, amount to from 50 to 80 inches, nay, in spots, 100 inches, while the rainfall (diminishing in reverse ratio) over this area is from 30 to 12 inches and less. “Thus, in Denver, where the maximum annual precipitation may reach 20 inches, the evaporation during one year was 69 inches. ‘This deficiency of 49 inches naturally must be supplied by waters coming from the mountains, where the precipitation is large and the evaporation low. (On Pike's Peak alone there may be 45.6 minus 26.8 or 18.8 inches to spare.)” Evaporation from the soil is dependent upon its covering, and this is important, as the soil in forests is always covered with dead branches, leaves, etc. In some experiments which were carried on in Germany during the months of July and August, 1883, to determine the amount of evaporation from different soils, it was found that from 1,000 square centimeters of bare ground 5,730 grams of water were evaporated, and that from the same area of similar soil covered with two inches of straw 575 grams were evaporated. This shows that the naked soil evaporated more than ten times as much as the covered soil. It is evident then that the soil covering has an important function in preventing evaporation. Wind-breaking Power of Forests. If the loss by evap- oration from an open field be compared with that of a forest- covered ground, as a matter of course it will be found to be less in the latter case, for the shade not only reduces the influence of the sun upon the soil, but also keeps the air under its cover relatively moister, therefore less capable of absorbing moisture from the soil by evaporation. In addition, the circulation of the air is impeded between the trunks, and this influence upon available water supply, the wind-breaking power of the forest, must be considered as among the most important factors o/ water preservation. Especially is this the case on the Western plains and on those Western mountain ranges bearing only a scattered tree growth, and where, therefore, the influence of shade is but nominal. The evaporation under the influence of the wind is dependent not only on the temperature and dryness of the same, but also on its velocity, which being impeded, the rate of evaporation is reduced. 36 ELEMENTARY FORESTRY. Interesting experiments for the purpose of ascertaining the changes in the rate of evaporation effected by the velocity of the wind were made by Prof. T. Russell, Jr., of the Signal Service, in 1887. The result of these experiments (made with Piche’s hygrometers whirled around on an arm 28 feet in length, the results of which were compared with those from a tin dish con- taining 4o cubic centimeters of water exposed under shelter) show that, with the temperature of the air at 84 degrees and a relative humidity of 50 per cent, evaporation at 5 miles an hour was 2.2 times greater than in a calm; at 10 miles, 3.8; at 15 miles, 4.9; at 20 miles, 5.7; at 25 miles, 6.1, and at 30 miles the wind would evaporate 6.3 times as much water as a calm atmos- phere of the same temperature and humidity. Now, if it is considered that the average velocity of the winds which constantly sweep the Western subarid and arid plains is from 10 to 15 miles, not rarely attaining a maximum of 50 and more miles, the cause of the aridity is not far to seek, and the function of the timber belt or even simple windbreak can be readily appreciated. Professor King has found in experiments made in Wiscon- sin that the influence of even a thin stand of woodland on the rate of evaporation was considerable. In one experiment made in the month of May the instruments were so placed as to meas- ure the evaporation to the leeward of a scant hedgerow six to eight feet high, having in it a few trees twelve feet high and many open gaps. It was found that at 300 feet from the hedge the evaporation was 30.1 per cent greater than at 20 feet, and at 150 feet it was 7.2 per cent less than at 300 feet. The experiment was made during a moist north wind. It is suthciently evident, therefore, that even a thin hedgerow exerts an influence that can readily be measured. In fact the presence or absence of protecting belts of trees under the conditions often existing on our prairies may make a difference between a good and a poor crop. All who are acquainted with our prairie sections know that great damage is often done to wheat, corn and other crops by the hot southwest winds which we are likely to have during the growing months. In Kansas and Nebraska during the sum- mer of 1894 immense tracts of corn, fully tasselled out, were killed by such winds. At the same time it was noticed that where corn was protected by trees or slopes of land, or where -1 WIND-BREAKING POWER OF FORESTS. 3 the humidity of the wind was increased by passing over bodies of water or clover fields, the injury was greatly lessened. What the possibilities of evaporation from hot and dry winds may be can be learned from statements regarding the ‘“Fcehn,” which is the hot wind of Switzerland, corresponding to the “chinook” of our western country. The change in temperature from the normal, experienced under the influence of the Fcehn, has been noted as from 28 degrecs to 31 degrees Fahr., and a reduction of relative humidity of 58 per cent. A Foehn of twelve hours’ duration has been known to “eat up” entirely a snow cover 2% feet deep. In Denver a chinook has been known to induce a rise in temperature of 57 degrees Fahr. in twenty-four hours (of which 360 degrees in five minutes), while the relative humidity sank from 100 to 21 per cent. The degree of forest influence upon rate of evaporation by breaking the force of winds is dependent upon the extent and density of the forest, and especially on the height of the trees; for according to an elementary law of mechanics the influence which breaks the force of the wind is felt at a considerable ele- vation above the trees. This can be practically demonstrated by passing along a timber plantation on the wind-swept plains. Even a thin stand of young trees not higher than five feet will absolutely calm the air within a considerable distance and height beyond the shelter. Professor King found that an oak grove 12 to 15 feet high exerted an appreciable effect in a gentle breeze at a distance of 300 feet. In a strong wind the effect of such a grove would be felt at a much greater distance to the leeward. At the Dominion Experiment Station in’ Assiniboia Dr. Saunders found on one occasion that windbreaks exerted an appreciable influence at from 50 to 8o feet to leeward for every foot in height, but this was during a very severe wind. It may probably be laid down as a general rule that windbreaks will exert an appreciable influence for at least one rod for every foot in height. ; It may not be necessary to state that the damage done to crops by the cold, dry winter winds is mainly due to rapid evaporation, and that plants are liable to suffer as much by win- ter drouth as by summer drouth. 38 ELEMENTARY FORESTRY. This is certain—that since summer and winter drouth, that is, rapid evaporation due to continuous dry winds, is the bane of the farmer on the plains, rationally disposed timber belts will do much to increase available water supply by reducing evap- oration. Evaporation, of course, goes on much less rapidly within than without the forest. How great this difference is in this section we have no exact figures to tell, but it is certain that it is much more than in Bavaria, where the following result was obtained:* In an experiment which was carried on to determine the amount evaporated from April to October*it was found that from a certain area without the forest 40.8 centi- meters were evaporated, within pine wood 15.9 centimeters and within deciduous woods 6.2 centimeters. This shows that the evaporation was six and one-half times as great in the open field as in deciduous woods. Transpiration. Another factor by which forests dissipate water supplies and which has been referred to (page 17) is transpiration. The quantity of water so used is as variable as the amount of precipitation, and in fact within certain limits depends largely upon it; that is to say, a plant will transpire in proportion to the amount of water which is at its disposal. Transpiration is also dependent on the stage of development of the plant, on the nature of its leaves and amount of foliage, on temperature, humidity and circulation of the air, on intensity of the sunlight, and on temperature and structure of the soil and on other meteorological conditions. Rain and dew reduce transpiration; wind increases it. The amount of transpiration depends considerably upon the thickness of the leaves; therefore the suriace of the foliage is not a reliable measure, but should be compared with the weight. In some European experiments carried on during the period of vegetation, the amount of water transpired by the different species per pound of dry matter in the leaves was as follows: TRANSPIRATION. 39 Pounds of Water. Bireli sand Mindemecco-te eek sea eae netieece aw eules 600 to 700 ASSlliie <3 oimieecetutine> waePniee eum eat leat nk Nin eat 500 to 600 HE Nc Let I hatin teed AN ede pm we OC RIEU EO 450 to 500 Maple wearin een ener ns tre tan oan eens: 400 to 450 CY ata errs Rese rata ROR ANY OS Tucan Wah ae ech VAP ESA 200 to 300 Spruce and “Seotely Pitiéw,.occccayescosiehes ae 50 to 70 IAT Sa Sicse es semen ane ees Aptaapn btn ae apa dener Tee hain) Suan = GOAL: AO: 1B} Wet baal 2h al nema ee Rare fe cree CNyt a Nam as 30 to 40 Average, deciduous trees..............-.0 000s 470 Average, evergreen trees........ 0.0000 c see eee 43 This shows that there is a great difference in the amounts of water transpired from deciduous trees and evergreen trees. In this case the deciduous trees transpired about eleven times as much as the evergreens. “The variability of transpiration from day to day is of wide range; a birch standing in the open and found to have 200,000 leaves was calculated to have transpired on hot summer days 700 to 990 pounds, while on other days its exhalations were prob- ably not more than 18 to 20 pounds. But while trees transpire large amounts of water, our agri- cultural crops and other low vegetation transpire much larger amounts to the same areas. A small factor in the dissipation of water supplies is the amount of water that is retained in the plant itself. As before mentioned this may amount annually to about 5,0co pounds per acre. The water in fresh cut woods forms a large part of their weight. In hard woods, such as Ash, Oak, Elm and Birch, it forms 38 to 45 per cent, and in soft woods 45 to 55 per cent or more. ELEMENTS OF CONSERVATION OF WATER SUPPLIES. In discussing the elements of dissipation as to the degree of their effect under forest cover as compared with the same ele- ments at work in the open field, we have seen that the shade, the low temperature, the relative humidity, the absence of strong air currents and the protective and water-holding capacity of the forest floor are all factors in the conservation of the water supplies. We have also seen that the quantity of water lost by evaporation, the greatest source of dissipation, may be more 40 ELEMENTARY FORESTRY. than six times as great in the open as in the forest. The only other conservative effect of forests on water supplies is their effect in retarding the melting of the snows. This acts as an important function in the prevention ot freshets by giving the snow a longer time to melt, so that the snow water has a bet- ter chance to sink into the ground. It is of course more evi- dent in evergreen than in deciduous forests. On the grounds of the Minnesota Experiment Station, where the woodland con- sists of a low growth of Oak, the snow is often retained in the woods a week longer than in the open. This often allows the snow water from the fields to almost wholly run off before it has begun to flow from the woods. Then again the daily flow of snow water from the woods is much shorter than from the open fields during spring weather, when we have warm days and cold nights, for it begins later in the morning and stops earlier in the afternoon. Under the dense shade and mulch of the cedar swamps of northern Minnesota the snow and ice often remain until the beginning of summer. The Indians claim there has never been a time when they could not find ice for their sick in the cedar swamps of that section. This retarding effect on the melting of snows in the spring and in preventing the run-off is of far greater importance in the case of streams that rise in the high mountains than in Minnesota and Wiscon- sin, where the land is more nearly level. Where streams have their sources in mountains, as those of Colorado and other Rocky Mountain States, the cutting away of the forests causes a heavy flow of water early in the spring and little water in the summer, when it is most needed for irrigation purposes. This has become so evident that the Chamber of Commerce of Den- ver, Colorado, recently petitioned the President of the United States to reserve such land in forests and administer it at public expense, and in their petition used in part the following lan- guage: “The streams upon which the irrigation system of Colorado depends are fed by the springs, rivulets and melting snows of the mountains, which in turn are nourished and protected by the native forests. Where the forests have been destroyed and the mountain slopes laid bare most unfavorable conditions pre- vail. The springs and the rivulets have disappeared, the winter snow melts prematurely, and the flow of the streams, formerly DISTRIBUTION OF WATER. 41 equable and continuous, has become fitful and uncertain. Floods and drouth alternating clearly indicate that the natural physical conditions of the region have been unduly disturbed. In winter and early spring, when heavy masses of snow have been accumulated on treeless precipitous slopes, snow and land slides frequently occur with disastrous result to life and prop- erty.” THE DISTRIBUTION OF WATER. The distribution or “run-off” of the water is often a more important factor in its economy than the quantity available. It is influenced by the surface conditions of the soil cover, by the porosity and structure of the soil and by the slope. There are two kinds of run-off, the surface run-off and the under- ground run-off or percolation. The former is likely to do injury by eroding the soil, while the latter is generally beneficial to vegetation in the formation of springs and in raising the water level in the soil. It is evident that the less surface drain- age and the more underground drainage the greater the spring- water supply and vice versa. We are, therefore, interested in determining the factors that increase underground drainage and reduce the surface flow. It is plain that whatever retards the flow of water over the land aids it in sinking into the soil. We find this exemplified in swamps, where the soft, rough ground retards the surface flow, and in forests, where the foliage checks the water in its descent to the ground and the forest floor retards the surface run-off. Theoretically such a cover should promote the flow of springs and maintain the height of water in wells, and in practice we find that this is often the case. In some cases springs had entirely disappeared after the clearing of near-by forests, but have commenced their regular flow since the trees have been allowed to grow again. Springs in turn influence the flow of water in rivers, so that forests about the headwaters of streams often have a most potent effect in maintaining their flow. There is in fact no influence of the forest that is of greater importance in the distribution of water supplies than its effect in retarding the run-off, even though its effect in pre- venting evaporation is very important. 42 ELEMENTARY FORESTRY. FOREST INFLUENCES ON WIND AND HAIL STORMS. We have seen that the wind-breaking power of the forest is avery important factor in retarding evaporation, and in prevent- ing the drifting of sandy soil and snow. Jn the forest the air may be rather still while in the open a piercing gale may be blowing; in consequence there are no blizzards in a wooded country. Tornadoes of great force have occasionally broken down wide areas of timber in this section, but instances are very rare in which they have continued for long distances through forests, and it is probably true that forests have a tendency to prevent their formation and perhaps entirely break up those of lesser violence. M. Becquerel is said to have found by careful study that in some parts of central France hail storms show a marked disinclination to enter forests, and yet occasionally they do so, but nothing of this sort has been noticed here. FOREST INFLUENCES ON FOGS AND CLOUDS. The influence of forests on fogs and clouds has frequently been mentioned. The fog seems to linger in the woods after it has cleared off elsewhere. Trees act also as condensers and gatherers of dew, hoar-frost and ice; the latter phenomenon is especially remarkable in the so-called ice storms, where the accumulation of ice on the trees is so great as to break them down. The load of ice on some large trees is probably a ton or more. In this case the tree acts simply as an inorganic body. IMPROVEMENT OF LAND ON WHICH TREES GROW. As has been shown, trees add large amounts of soluble min- eral matters to the soil through the fall and decay of their leaves. In the same way they add large amounts of humus to the land, which helps to keep the soil porous and yet makes it more retentive of moisture and gases. The roots of trees often penetrate deep into the soil and bring up plant food that would not be reached by agricultural crops. A part of this is returned to the surface soil by the yearly fall of the leaves and in the twigs and branches that are left on the ground when the tree is cut down. The roots deepen the soil, and by their decay fur- nish plant food to the soil and leave channels through which WHY THE PRAIRIES ARE TREELESS. 43 water and air may enter the subsoil. It has been estimated that after a sandy soil in New England is so exhausted that it will produce nothing but red mosses it may be renewed to its pristine vigor and productiveness by the growth of trees on it for thirty years. WHY THE PRAIRIES ARE TREELESS. This question has been answered in many ways, but often, it would seem, by persons not acquainted with the principles of forestry. It seems that the best way of getting a clear under- standing of this matter is to consider two extremes of tree growth. astern Minnesota has a rainfall of perhaps 26 to 35 inches and a comparatively moist air, and at least during a part of the year is well adapted to the growth of the hardier kinds of trees. Here we find the White Pine, Basswood, Oak, Elm, Poplar and other trees attaining large size. Western Dakota has a very light rainfall, mostly in the spring, and a very high rate of evaporation. Trees can scarcely be made to grow in this section without irrigation, and the low vegetation, the grasses, which require a less amount of water, replace the trees. It is evident that between locations having such extremes of tree growth there must be a place where the trees give way to the lower forms of vegetation. Such a meridianal zone is found in central Minnesota, and though it has probably changed with fluctuating rainfall its general location has remained practically the same for many years. The location of this zone was proba- bly gradually driven eastward, for many years previous to set- tlement, by the practice of the Indians of burning over prairies in order to furnish good pasturage for the buffalo. Of late years, since the prairie fires have been largely prevented, the tree line has moved westward and gained a little on the prairies. When left to itself the western limit of this tree zone would not make very great progress westward, but with man’s assistance in cultivation and various other ways it may be extended much farther towards the arid regions than if left to natural conditions. So we find that, while great sections of the interior of this coun- try are treeless on account of lack of water, trees planted on them and properly cared for may often grow thriftily. But trees planted on our prairies always require more care to make them 44 ELEMENTARY FORESTRY. do well than those planted in sections of greater rainfall, and we should not expect them to grow as large as in the timbered sections without irrigation. RAINFALL AND HEIGHT OF WATER TABLE IN THE LAND. A few years ago it was argued by many friends of tree plant- ing that it was practicable by the planting of trees to increase the rainfall and prevent evaporation in the great continental plain sufficiently to materially change the climate. The large rainfall and the good crops produced for a number of years in the drier portions of this area after considerable planting had been done seemed to endorse all that the most enthusiastic of tree planters claimed. But it must be very evident to any care- ful student of the subject that such small plantings as were made, even had they been maintained, could scarcely have had any appreciable effect on the general climate of so vast a territory. It is very evident, too, from a study of the annual rainfall, that it has fluctuated greatly in this section, and that we have perhaps not recorded the least or the greatest amount for any one year. There are some facts that seem to show plainly that there must have been a time when the water level of our lakes was much lower than it is now or than it was during the very dry years from 1890 to 1895, when the rainfall in most cases pro- duced no flow in the streams. There is a lake near Devils Lake, N. D., where in 1890 the old overland trail leading west termi- nated abruptly on one side of the lake and was taken up again in the continuation of its direction on the opposite side. The trail is clear and distinct, showing it to have been of compara- tively recent use. It is a reasonable inference that when this trail was in use this lake was dry. There are places near the shores of Devils Lake where upright stumps are standing sub- merged in water. The same phenomenon has been noticed in other places. These are almost certain indications of a time or times when the beds of these lakes, where the stumps are, were out of water or very nearly so for a sufficient length of time for the trees to grow. The climate must have been very dry, and the great continental plain, or at least portions of it, must have bordered pretty closely upon a desert, and the “Great American Desert” may have beena reality. It would seem, then, HOT WINDS. 4 oO that the knowledge we are gaining of the unknown past, as well as the records of more recent years, point to the recurrence of great fluctuations in the annual rainfall of this section, and it seems probable that such changes follow series of years, and that the recedence of our lakes may be followed by periods of higher water. But the influence of the cultivation of the soil on water sup- plies must be taken into account in this connection, for it is undoubtedly true that man has changed the conditions of the soil sufficiently to greatly influence the run-off. The breaking up of large areas of prairie sod, with its low rate of evaporation, and the planting of such land to agricultural crops with a rela- tively high rate of evaporation, has resulted in a loss of soil water. Then the cultivated soil takes up more water than the sod-bound prairie slopes, so that it does not have so good an opportunity to collect in lakes and swamps, which often supplied the water of wells. And further, the straightening and cleaning out of water courses, and the draining of swamps in the effort to get arable land, has had a similar effect on subsoil water sup- plies. HOT WINDS. The hot winds of the plains which so often cause serious injury to farm crops in Kansas, Nebraska and the Dakotas have been ascribed to the arid “staked” plains, whence, taking a north- easterly direction, they draw all the moisture from the vegeta- tion with which they come in contact. The view has also been presented that they have their origin on the Pacific Coast, ascend the Rocky Mountains, lose their moisture and descend on the eastern slopes. But all theories that ascribe their origin to a distant source are inadequate to explain their phenomena. For instance, all who are acquainted with these winds know that they blow only during very dry weather, when the earth is heated very hot, that a good rain speedily brings them to an end, and that they blow only during the daytime, commencing about 9 A. M. and continuing until sundown. This daily move- ment is often constant for several weeks, showing that there is evidently some connection between them and the course of the sun. For these reasons and others which would require too 46 ELEMENTARY FORESTRY. much space to give here, the best authorities unite in attributing them to local origin. Mr. George C. Curtiss describes the process of the produc- tion of a typical hot wind as follows: “The necessary condi- tions are those of the ‘warm wave,’ namely, a diminishing pres- sure to the northward, producing southerly winds which initially elevate the temperature above the normal. A cloudless sky favors an intense insolation, as a result of which the dry ground is soon raised to an extreme temperature, and the air is heated from it by radiation, reflection and conduction. The resulting diminution of density due to the rise of temperature furnishes impetus to previously existing horizontal currents, and by 10 o'clock in the morning the hot wind is fully developed. Hun- dreds of miles of hot dry earth contribute to maintain and feed the current, and, gathering strength as the sun mounts higher, the hot wind sweeps over the defenseless prairie. Neither hills nor forests rise in its path to break its power or dispute its sway, and, with no enemy save the tardy raincloud, the fetid blast sucks out the life-sap of the growing grain. It will be readily seen then that each of the states, Kansas, Nebraska and North and South Dakota, develops its own hot winds and cannot charge them to the account of its neighbors.” The local origin of these winds at once suggests the desira- bility of frequent windbreaks on the prairie farms, as offering the most practical way of breaking them up. Irrigation of large areas will also undoubtedly do much to prevent them. CHAPTER IV. TREE PLANTING ON PRAIRIES. The subject of tree planting in this section naturally divides itself under the two heads of prairie planting and forest planting. The former relates to the limited planting of trees on our prairies for ornament, protection and use. and the latter to the care and management of timber lands and the planting of trees for profit from their growth. Our people are very generally impressed with the importance of prairie planting for protection and orna- ment, but are too prone to regard the care and management of timber lands for the production of timber crops as a matter of little concern and very impracticable. (The subject of the regen- eration of forests is treated in the chapter on forest Planting and Treatment.) PRAIRIE PLANTING. Whatever the ulterior object of prairie planting, the subject of protection to the buildings, their occupants and the cattle in the field should always be first considered. Our crops in this sec- tion are most liable to injury from the southwest wind of sum- mer, which dries them out, and the northwest wind of winter, which blows the snow from the land, causing it to lose the snow water. It also causes a loss of evaporation, which goes on even in winter from the bare ground, and from exposed crops, causing them to winter-kill. The same winds are also the most uncom- fortable to the occupants of farm buildings, and are most likely to cause dust storms, which should be especially guarded against. Windbreak is a general name given to anything that gives protection from wind. On the prairies it is often applied to a single row of trees planted for protection. Shelterbelt is a term more often used to signify several or a large number of rows of trees, but the term is often used inter- changeably with windbreak. Grove is a term that refers to comparatively large bodies of trees which may be planted for shelter, fuel or other purposes. 48 ELEMENTARY FORESTRY. Protection to Buildings may be furnished by a few rows of a grove of trees. It is generally best to locate the buildings in a grove, or grow one up around them, so that protection may be afforded from every quarter to the best advantage. The garden should also be included in the grove or shelterbelt about the buildings. Distance ofthe Trees from the Buildings and Roadways. Of whatever the protection consists, it should not be close to the buildings or to any paths which are used in winter, for the snow drifts which always form to the leeward of such protection may become a great nuisance under such circumstances during win- ters of great snowlall. The windbreak had better be placed about one hundred feet back from the buildings, and if shade is wanted it can be obtained from scattered trees near the buildings, which will not drift the snow. The same rule applies to the planting of trees on the north side of a roadway. The drifts of snow which would®be formed to the leeward of a windbreak so planted would take longer to thaw in the spring, and would keep the road muddy and in poor condition after those that were not protected had become dry and firm. A row of trees is very ap- propriate by the side of a street or roadway and affords a pleas- ant shade, and if not planted too closely together will not drift the snow sufficiently to be an objection. Protection to Crops by Windbreaks. The objection to windbreaks close to driveways may also be made against their use in fields, for they often keep the land for a short distance to leeward wet and in unfit condition to work after the rest of the field has become dry. This is an objection where spring grains are grown, but to winter grains it is an advantage. On the other hand, the protection of a windbreak may give a much need- ed or beneficial covering of snow to crops on the leeward side. The protection from dust storms and drying winds has alréady been mentioned. The important question is how to get the ad- vantages without the disadvantages. In many sections the dis- advantage of having the snow linger on the field near the wind- bréak may be overcome by leaving a strip of land near it in permanent meadow, or use it for a rotation that does not take in eréps that require very early planting. But even with spring- planted grains it is more than probable that windbreaks properly WINDBREAKS. 49 planted are an advantage when their benefits are considered for a series of years. It ofttimes happens that low windbreaks are more beneficial than high windbreaks in holding the snow on the land, for the high windbreaks often form a great drift that may remain late in the spring, while the low windbreak nowhere forms a large drift, but spreads the snow for long dis- tances. Professor Budd says that in parts of the great conti- nental plain of Russia, where the climatic changes are much the same as in this section, the use of low windbreaks in wheat fields is very common. Height of Windbreak. From the preceding paragraph it will be seen that low windbreaks may often serve a better pur- pose than high ones in protecting fields. Exactly what is meant by a low windbreak may be an open question, but for the pur- poses of this discussion a low windbreak may be considered one under twenty feet in height. In Russia and at the experiment station at Indian Head, Manitoba, windbreaks of Artemisia tobolksiana, which seldom grows more than eight feet high, are often used. About farm buildings windbreaks cannot be too high, and for this purpose the largest, longest-lived trees should be used. Kinds of Trees for a Windbreak. In too many instances too many tree planters on the prairies have put out exclusively quick-growing, short-lived trees, such as the Cottonwood and Lombardy Poplar, and after fifteen or twenty years they have found their trees dying and nothing coming on to take their places. The quick-growing kinds are very desirable as a pro- tection for the near future, but they are often short lived and should never be planted alone. Among them should be planted a sufficient number of long-lived and perhaps slower-growing kinds, to afford protection in later years, when the short-lived kinds have died out. ‘The soil and location have much to do in determining the longevity of varieties; for instance, the Cot- tonwood and Lombardy Poplar are generally short-lived trees when planted in this section, but when planted in locations where their roots reach the permanent water level their period of life may be considerably lengthened, and they may then even be regarded as long-lived trees. In starting a grove or windbreak on the prairie in this sec- tion, there is probably no better tree to begin with than the 4 50 ELEMENTARY FORESTRY. White Willow. It is quick-growing, rather long-lived in most situations, makes good summer fuel and renews itself very rap- idly from the stump. The Green Ash would probably rank next Figure 3. A young White Willow windbreak on dry prairie at Coteau Farm. Grown entirely by mulching after being well started. as a pioneer tree. The White Elm is also very valuable for this purpose, but generally should follow the White Willow. The Cottonwood may sometimes, though very seldom, be the best to use, but on average prairie land it would be better if the White Willow or Green Ash were always planted instead. After a good windbreak has been secured it is safe to plant out the hardy coniferous evergreens and such trees as the Mountain Ash, European White Birch and other similar orna- mental trees. Wind protection is beneficial to all trees and necessary for many of our best ornamental kinds and often makes the difference between success and failure in growing them. Distance Apart. In the planting of groves we should aim to get the Jand shaded by the trees as soon as practicable, and to keep it covered with a canopy of leaves. The United States government recommended the planting of trees four feet apart each way, with the idea that when so planted they would quickly shade the ground and consequently keep out grass and retard evaporation. Some successful plantings have been made on this plan, but when planted so closely together the branches grow into the rows after a few years and cultivation must be discontinued. In this section, where we have so much very DISTANCE APART. 51 bright sunshiny weather that grass can grow under foliage that would kill it out in a more humid climate, we find that trees planted four feet apart each way seldom afford sufficient shade to kill the grass under them for many years. This is especially true of such trees as the Cottonwood, Lombardy Poplar and White Elm when planted alone, as they have open foliage that does not furnish a dense shade. Among tree planters who have had a large experience in prairie planting there has been a tendency of late years to plant two feet apart in rows eight feet apart, and some of our most successful planters prefer even more room than this between the rows. When plantings are made 2x8 feet the same number of trees are required for an acre as when planted 4x4 feet, but the former distance has the advan- tage over the latter in that the space between the rows can be cultivated for perhaps ten years or more, by which time most trees will have formed a dense shade and be able to take care ‘of themselves. Where a much greater distance than eight feet is allowed between the rows we generally fail to ect forest con- ditions for many years, and to that extent fall short of an impor- tant requisite in prairie planting. The distances given here might need to be modified to suit different varieties and local climatic conditions. Clear Plantings. Most of the plantings on our prairies consist wholly of one kind. In some cases good results are thus obtained, but they are seldom as satisfactory as plantings made up of several different kinds. One of the greatest drawbacks to plantings made up entirely of one kind is the fact that drouth, insects or fungous disease may destroy the whole planting at one time, while in a judiciously mixed planting this could hardly occur. Mixed Plantings, when properly made. have the following advantages: (1) They make possible the growing of species that form a protection in the least possible time, and still have coming on in the same grove longer-lived and better kinds to take their places. (2) Many kinds that are somewhat tender are helped very much by being grown among the hardier kinds until well established. In this case the protecting trees are called nurse trees. The Scotch Pine is seldom a success when standing alone on our Western prairies, but when partially pro- tected by some deciduous tree it stands very well. The same 52 ELEMENTARY FORESTRY. is generally true of Hard Maple in this section and of Catalpa and Black Walnut in Southern Minnesota. (3) In good mixed plantings the ground is more likely to be properly shaded and protected from winds than it would be in clear plantings of such thinly-leafed species as the Cottonwood or White Elm, which do well and afford good shade when mixed with Green Ash bs Figure 4. \ good tree claim. Planted by Mr. Gardner, of Lyons county. Located on high prairie. Soil very dry. Ilas planted about 30 acres in trees. or Boxelder. (4) Mixed piantings are most interesting and ornamental. (5) They attract more birds by their better pro- tection and the greater variety of food offered. (6) While the chance of injury to some of the species by climatic changes, dis- eases and insects is increased, the possibility of total loss from any or all of these causes is reduced to the minimum. The Most Important Constituent of a Prairie Grove of mixed trees in this section should be some well-known dura- ble kind, as the Elm, Ash or Boxelder, of which there should be a sufficient number to completely shade the ground when the others are gone. On the outside, especially on the north and west, it is often a good plan to put at least » few rows of White ae) TREES FOR MIXED PLANTINGS. 5: Willow or possibly Cottonwood to furnish a quick protection. The rest of the grove should consist of hardy sorts, and may include some of the evergreens and such fruit-bearing trees or shrubs as the Wild Plum, Wild Black Cherry, Russian Mul- berry and Juneberry. These latter furnish food for the birds and may often be a help in supplying the home table. The plan of planting with a view of providing some food for birds is not mere sentiment, for they protect our gardens from many insects, and if we furnish an abundance of Russian Mulberry they will not trespass much on our strawberries or raspberries. It is the author’s opinion that in all our prairie planting we should pay more attention to using our native fruits and Rus- sian Mulberry as plants of secondary importance. List of Trees for Mixed Plantings. Some suggestions may be found in the following lists, but several other trees might often be used to give a variety or a tasteful display. For Porous Moist Soils in Southern Minnesota. White Elm, Black Walnut, Green Ash and Hard Maple in equal quan- tities with a scattering of the fruit plants. The Hackberry may wholly or in part take the place of the White Elm, and the Box- elder the place of the Green Ash. The White Willow, Bass- wood and Soft Maple would also do well in such a location. One of the main kinds might be replaced by the White or Nor- way Spruce, Douglas Fir or White Pine. In fact such land as this will grow any of the trees adapted to this section. For High Prairie Soils in Southern Minnesota. Green Ash, Boxelder, White Elm and White Willow in equal quanti- ties, with scattering of fruit plants. Basswood might be used to a limited extent, and White Spruce, Red Cedar, Norway Pine, White Pine or Scotch Pine might be used in the place of one of the main kinds. For Moist, Porous Prairie Soils in Northern Minnesota. White Willow, White Elm, Boxelder, Basswood and Green Ash in equal quantities, with a scattering of fruit plants. In some localities it might be best to use Cottonwood on the out- side of the grove. Hackberry might take the place of part of the White Elm and White Spruce, Arborvite, Norway Pine, Red Cedar, and some other conifers might be used to a limited extent, ht ELEMENTARY FORESTRY. For High Prairie Soils in Northern Minnesota. Cot- tonwood, White Willow, Boxelder and White Elm in equal quantities, with a scattering of fruit plants. White Spruce and native Red Cedar might also be used in a small way. Lists of trees commonly planted, arranged in the order of their hardiness: Deciduous trees—Green Ash, White Willow, White Elm, Boxelder, Basswood, White Poplar, Hackberry, Soft Maple, Canoe Birch and Yellow Locust. Evergreen trees— Red Cedar, Dwarf Mountain Pine, Jack Pine, Bull Pine, White Spruce, Austrian Pine, Scotch Pine, Douglas Spruce, Norway Pine, Norway Spruce and White Pine. Size of Trees. In the case of deciduous trees it is gener- ally best to start with one year old thrifty seedlings, although trees two years old may often be used to advantage. The Oak, Walnut and similar trees are better started from seeds where they are to remain, and the White Willow should be started from cuttings. Seedling Flm, Ash and Cottonwood may often be pulled from some river bank or lake shore, or bought of nursery men at a very low figure, or they may be raised from seeds. White Willow cuttings can generally be obtained from some neighbor or from nurseries. In the case of conifers, transplanted seedlings should be used. Whatever the source of any stock that is to be planted, it should be thrifty and vigorous and not weak or diseased. Methods of Planting. The methods used in prairie plant- ing are much the same as for transplanting in the nursery. In every case much pains should be taken to have the soil in the best condition. It is generally better to delay planting for a year than to attempt it in poorly prepared soil. Tree plantings have been made on our prairies by sowing tree seeds broadcast in autumn after first carefully preparing the soil, but the plan is seldom successful. A start can, however, be made from seeds by planting the seeds in hills either alone or with corn or beans. In the latter case the tree seedlings often do very well and do not interfere with the growth of the crop. The seedlings are culti- vated in the spring alter the crop is removed and as they are in rows this is a very simple matter. The common and generally most successful plan with trees that can be easily transplanted is to start with seedlings and plant in rows. The simplest and easiest way of doing this is to furrow one way, mark out the CULTIVATION AND THINNING. 55 other way and plant the trecs in the furrows at the intersections. If Black Walnut or any of the oaks are wanted in a mixed plant- ing it is generally best to plant the other species first and put in the nuts or acorns afterwards. Where it is desirable to plant seedlings or cuttings to fill vacancies, a pointed stick or spade may be used to make the hole. Whatever method is used in planting, it is most important that the soil be packed firmly around the roots, so they will not dry out. If the soil is dry it cannot be made too solid around the roots. If cuttings are used they should be made about 14 inches long, and in planting be pushed into the loose soil in a slanting position, leaving only one bud above the surface, as recommended in the planting of cuttings. . Cultivation should be commenced shortly after planting and be repeated often enough to keep the top three inches of soil loose, so as to form a dust blanket to retard evaporation during dry weather. The soil should never be allowed to become baked hard after a rain, but the crust should be broken up with a horse cultivator as soon after a rain as it can be worked. Cultivation should be discontinued after the first of August, in order to encourage early ripening of the wood. The weeds that grow after this time of year will do no harm. One of the best tools for early cultivation of small seedlings is Breed’s Weeder, which may be worked both ways and cleans out the weeds to perfection. The ordinary corn cultivator is also a good implement for this purpose. Later cultivation should consist of working the soil with a one-horse cultivator or plow. If the horse implements are properly used there will be no necessity of hand hoeing, for the few weeds that grow in the rows of trees will do no injury to them. Some planters sow oats among the young trees for protection when cultivation ceases, but if field mice are abundant it may be best not to do so. Late in autumn of the first year or two after planting some soil should be turned towards the trees with a plow, to protect them. e Thinning. In growing prairie groves we should always aim to have the tops of the trees just touch one another without serious crowding, but still have the soil shaded and protected from wind. In order to bring this about, the grove must be thinned occasionally, for although the trees would thin them- 56 ELEMENTARY FORESTRY. selves if left alone it would be at the expense of growth and per- haps cause serious injury. ‘T'rees that are crowded together may suffer more from drouth than those that have plenty of room for their roots. This is especially true of tender trees on dry land. If the trees begin to crowd one another the poorest should be removed, but this should be done carefully and never to such an extent as to let in the sunlight, which would encour- age the growth of grass, weeds and side branches. Thinning may be done at any time, but if the wood taken out is to be used for fence posts or poles it would be better to cut in winter and peel at once to aid it in curing. The Blowing Out of Small Seedlings planted in prairie soil is not uncommon where they are in very exposed situations. The movement of the young seedlings by the wind keeps the soil loose around them, which the severe winds blow away. Occa- sionally by such means the roots may be left three or four inches out of the ground the first season. In such very severe loca- tions it is often a good plan to mulch the soil with straw or sim- ilar material until the seedlings are well established, after which they may be cultivated, or the mulching process may be contin- ued until they will take care of themselves. The Proper Location of the Buildings on a Farm is a very important matter and seldom receives the attention which its importance demands. The position of the buildings determines the location of the drives and of the shelterbelts if any are to be planted. There are many factors which should enter into the study of this question, among the first of which is the lay of the land. Good drainage and good water are the first requisites for the location of a home, after which come con- venience and beauty. It is very desirable that the first location be made just right, since when other improvements and build- ings have been commenced it can seldom be changed without much extra expense. In the case of most of our farms the sub- ject of plans is conspicuous by its absence, as small cramped grounds about inconveniently arranged buildings bear abundant evidence. In figure 5 is shown four plans suggestive of the proper loca- tion of the shelter belts about farm buildings located on level prairies, and varying according to the location of the main high- way. Five acres in the form of a rectangle, 25 rods wide and 32 LOCATION OF FARM BUILDINGS. aT rods long, are included in the land about the buildings, and this has a shelter belt five rods wide on the north and west sides. and on'the south side two rows of trees ten feet apart, with the NORTH. Figure 5. Suggestion for laying out the grounds about the buildings on prairie farms, showing arrangements adapted to a highway located on four different sides. Size 30x37 rods, enclosing five acres, exclusive of shelterbelt on north and west sides five rods wide. Rows of trees indi- cated. See figure (6) for further details and suggestions. trees one rod apart in the rows. Within this enclosure are all the farm buildings, orchard, fruit and vegetable garden, barn- yards, etc. The house should be within too feet of the road, and the stock buildings at least 100 feet from the house and garden. About the buildings and garden some supplementary wind- 58 ELEMENTARY FORESTRY. breaks and ornamental trees and shrubs will be needed for wind protection and for beautifying the place. This arrangement gives plenty of room for the buildings, barnyards, garden and orchard, and, while all the land enclosed may not be needed for these purposes, the remainder is well adapted to the growing NORTH. RSE OY- I ane ears aa aes cae ald as Weare ae dca Pas * Orchard [ li Megetebles. |i co (2. 33 30 rods----- Tigure 6. Suggestion in detail for laying out the grounds about the buildings on a prairie farm. Highway on south, size 30x37 rods enclosing five acres; windbreak on north and west five rods wide. Two rows of trees next to highway. Rows of trees indicated. of general farm crops. The plans are only suggestive and no attempt is made to work out details, and there are compara- tively few farms that they would fit exactly. For instance, while itis desirable to have the buildings centrally located, their posi- tion must frequently be pushed to one side on account of a swamp or lowland which is not suitable for them, or their posi- tion may be determined by a beautiful natural grove. Figure 6 shows a plan for a south front drawn on a larger scale. It may often be desirable to change the shape of the land enclosed, but LOCATION OF FARM BUILDINGS. 59 in the great majority of prairie farms a plan similar to this would work out to good advantage and the area enclosed by wind- breaks could often be increased to ten acres to good advantage. A rule that should be carefully followed in all tree plantings is that the view from the most commonly used rooms of any- thing that is suggestive of pleasant associations or that is especially interesting or entertaining should not be cut off. Under this head would be included the view, from the living- room windows, of the traveled wagon road or perhaps of the railroad, of the neighboring houses or perhaps a nearby lake, and of the important fields on the farm, especially those where stock is pastured. ‘hese views can generally be secured without seriously impairing the value of the windbreaks, by cutting small openings in them or perhaps by simply shortening the trees, so that they will not interfere with the line of sight. CHAPTER V. FOREST REGENERATION AND TREATMENT. The timber lands of Minnesota should, as a rule, be managed so as to get the greatest cash returns from them, for that only is practical forestry which has this fundamental feature always in view. Our virgin forests have contained, and those remaining now contain, a large percentage of trees past their prime and losing in value each year they stand. Such forest products should be worked up as soon as a good market is found for them. In virgin forests there is no increase, the annual growth being just balanced by the annual decay under normal conai- tions. The Cultivation of Trees on timber lands in this section has never received much attention, and the only data as to the rate of increase that we have to follow are what can be obtained from the native forests, and these are for this reason only approximately correct. In European countries and elsewhere it has been proved by long experience that more timber is grown per acre, and that the growth is much more rapid, on land where some attention is given to systematic forestry than on that which is left to itself, and it will seem reasonable to believe this, when we consider that much of the energy of trees may be expended in fierce competition with neighbors, which may weaken them all and perhaps bring about unhealthy conditions, and that natural forest land is generally unevenly stocked with trees, many of which are rotten or otherwise defective, and often with those that are not the most profitable kinds to grow. In the cultivated forests unnecessary crowding is prevented by judicious thinning, and the land is kept evenly and completely stocked with the most profitable kinds. Succession of Tree Growth is an expression sometimes used as though there were a natural rotation of trees on the land. There is nothing of the sort. Sometimes hard woods will follow pine, or the pine the hard woods, where the two were mixed at FOREST REGENERATION AND TREATMENT. — 61 Figure 7. Virgin Forest. C White and Red Pine mixed. Near Mille Lacs. Good Natural Regeneration. 62 ELEMENTARY FORESTRY. the time of cutting and there was a young growth of one or the other kind which had a chance to grow when its competitor was removed. Where land is severely burned after being cut over, the trees that show first are gencrally the kinds with seeds that float long distances in the wind, such as Poplar and Birch, or those having fruits especially liked by birds, such as the Bird Cherry, which is very widely distributed. These show first on account of getting started first. The pine and the other trees may come in later owing to their being seeded later or owing to the later advent of conditions favorable to their germination and growth. It may happen in the case of burnt-over pine land that pine seed is distributed over it the first year after it is burned, but owing to there being no protection from the sun the young seedlings of White and Norway Pine which are very delicate, are destroyed. After a young growth of Poplars has appeared the pine seed may find just the right conditions for growth for a few years and finally get ahead of the poplars and crowd them out, while in the meantime it is being much improved by the presence of the poplars, which grow rapidly and force the pines to make a tall growth. On the other hand, however, the poplars, birches and other trees and shrubs and even weeds may sometimes make so strong a growth as to kill out the young pine seedlings if they are not sufficiently well established at the time the mature growth is cut. Regeneration is a term commonly used in forestry to sig- nily the renewal of forest trees upon the land. It is a convenient term and well worthy of general introduction into the forest literature of this country. The different forms of regeneration may be referred to as (1) regeneration by natural seeding, (2) regeneration by artificial seeding, (3) regeneration by sprouts and suckers, (4) regeneration by planting seedlings, (5) regen- eration by planting cuttings. The method of regeneration best adapted for one section may not be at all fitted for another under different conditions, and often it is best to combine two or more of the different forms of regeneration. Regeneration by Seed. Where natural regeneration by seed can be easily brought about, it is generally the best practice. This is especially true in sections where timber is comparatively cheap, as is generally the case in this country. It may be greatly assisted by stirring the surface cf the soil in good seed NATURAL REGENERATION. 63 years, and in other ways bringing about conditions conducive to the germination and growth of the seeds. Where it is prac- ticable to use it, a disk harrow is an admirable implement for breaking up the forest floor so as to allow the germination of seeds. Where a disk harrow cannot be used to advantage, and it can seldom be so used on new land in this country, it is a good plan to use a drag made by tying together several oak branches or small logs. Good seed years do not occur very often in our most desirable species, and it is very important to take advantage of these good years when they do come. At such times it is often a good practice to make extra cuttings in order to let in light and air, as well as to stir the soil and so make it possible to secure a good catch of the seed. The methods adopted to secure natural regeneration by seed may be divided into three systems, each of which may be best adapted to some special conditions. These are known (1) as the Selection Method, (2) as the Strip Method and (3) as the Group Method. The Selection Method refers to the cutting of the mature trees and to the removal of inferior trees to make room for the better kinds. In this system much care should be exercised to prevent the growth of grass, which generally comes in when the cutting is done more rapidly than the seeding trees can seed the bare land. On the other hand it is just as important to exercise care that the young seedlings which have started have sufficient light so that they can make a good growth and not be shaded out by the older trees. The removal of a single tree often lets in so very little light that seedlings cannot get a good start. On this account the group method is probably best adapted for general use. Strip Method is a term that is applied to the system where the trees are removed in narrow strips across which the remain- ing older trees can easily scatter their seed. The best width of strips will depend on the species and the local conditions. Some who advocate this method claim that the strips should not be wider than the height of the trees, while others would allow strips three or four times the height in the case of the elm, maples and pine, and in the case of birch even eight times may not be too much. Such strips should generally begin on the side opposite from the prevailing winds at seeding time, so the G4 ELEMENTARY FORESTRY. seed will be blown onto the denuded land. In the case of hill- sides the strips should generally extend along near the sum- mits, and successive strips should be on the lower sides to pre- vent washing of the soil. The strips may extend on one or two sides, and in shape should often be adapted to the contour of the land. 3 The Group Method is a system of cutting strips suc- cessively on the inside of certain groups. This may be termed a Figure 8 Diagram illustrating the system followed in the group method of cutting. Cuttings are begun at points marked 3, and are gradually extended by successive cuttings as indicated by figures 2, 3, 4 and 5. After Schlich. natural method, and for general use, especially in mixed woods and where the land and conditions are quite valuable, it is much REGENERATION BY ARTIFICIAL SEEDING. — 65 the best. It gives a chance to adapt the method of cutting to the different species and to the different conditions which may be found in the forest. For instance, a tamarack swamp, dry knoll covered with oak, a steep hillside, and level, rich, rocky land, each covered with the trees peculiar to it, would very likely all be included in almost any forest tract of any considera- ble size in the northern states, and each portion should receive special treatment. We can begin with one group or several, and we can start our regeneration in each group perhaps where there is already a good growth of young trees. In fact this sys- tem gives us a chance to begin regeneration where the greatest necessity or the best chance for it already exists. The size of the opening will depend here as in the strip method on the species grown and their conditions. Generally the first openings will be from one-fourth to one-half acre or more, and the strips taken around it should in width not greatly exceed the height of the trees in the strip next to be cut. Of course the regeneration in any case should be managed with the same care that should be given to any well managed forest to bring about the predominance of the most valuable kinds under the best light and soil conditions. Regeneration by Artificial Seeding. Occasionally it may be desirable to sow seed in woodlands. This is especially so in the case of some of our nut trees such as black walnut, butter- nut and oaks, which readily renew themselves by such means. Tn the case of pine and Spruce. however, success is quite uncer- tain under such treatment. Perhaps it is most certain with pine and spruce where it is practicable to furrow out with the nlow, as for instance it might be on some of the sandy lands of Min- nesota where furrows might be run between the trees or the land loosened in patches with a hoe. In this case the standing trees afford the proper shade conditions for the seedlings. In the case of clear fields, it is quite a simple matter to sow the seed in furrows. Where the moss is thick on the surface of the soil, it is a good plan to cut it off in squares, or long strips may be sown alter preparation. The seed will seldom grow if it is sown in deep or thick moss. Where seed is sown broadcast over ordinary forest land the seedlings are liable to be killed out by the weeds, which generally come in quickly as soon as the sun- light is allowed upon the soil. Pine and many other seeds are o 66 ELEMENTARY FORESTRY. sometimes sown in clear fields with oats, when the straw protects from the sun in summer and the stubble holds the snow and acts as winter protection. Seed of ash, maple, elm and some other trees may sometimes be sown in the hills with corn to advantage in prairie planting, and willow cuttings may also be used in the same way or with beans. Natural Reseeding of the land is then almost the only practical means of restocking the land in this section, which should receive attention here, as other methods are too expen- sive. It generally takes place in this section, and the only rea- son why it is not more successful is the frequent destruction of the young seedlings by fires. The small crooked branching pine and other seeding trees that are always left by lumbermen in their operations here, and generally considered worthless, per- form a very important work in producing seed, and it is a pity that there are not more such trees leit to produce seed for our cut-over lands. When such trees escape the first burning after the land is cut over, they often remain for twenty years doing their blessed work of distributing seed each year, and when the conditions exist for germination and growth the seed grows and lives. Sometimes where such trees are not left by lumbermen, or where they have been destroyed by fire, it has taken twenty years to get the land properly reseeded to White Pine by the slow process of seeding from trees at a distance of half a mile or more. The Covering of Tree Seeds in Woodland, whether the seeds are sown naturally or artificially, can often be best accomplished by stirring up the soil with a strong harrow or a brush drag made of the branches of an oak or other tree having strong wood. This may sometimes be done most advan- tageously before the seeds fall, and at other times alter they have fallen. Where the soil is made loose and the forest floor is broken up before the seeds fall, they are generally sufficiently covered by wind and rain. ‘Shey may sometimes be covered most satisfactorily by driving a flock of sheep over the land after the seed has fallen, the feet of the sheep pressing the seed into the ground. Regeneration by Planting Seedlings. This form of regeneration is practiced to a considerable extent in sections where timber is high in price. Tt is often the most economical REGENERATION BY PLANTING SEEDLINGS. 67 way of securing a stock of coniferous trees upon the land. Under the conditions which frequently prevail on our cut-over land there is very little chance for natural or artificial regenera- tion of desirable kinds by seed, owing to the fact that all the seed-producing trees were cut when the land was logged, or have since been destroyed by fire and the ground covered by a Figure 9. Old pine cuttings after being once burned over. growth of weeds and inferior trees; but seedling pines can often be set out at intervals ‘of perhaps ten feet apart each way where they would be sufficiently crowded by the weeds, poplar and other fast growing trees, so that they would take on an upright form quite free from side branches until their tops interlaced, after which they would crowd one another. Such planting can be done here at an expense of about five dollars per acre. It is necessary for the success of such work that weeds be pre- vented from smothering the trees, which they are liable to do 68 ELEMENTARY FORESTRY. until the seedlings get well started, and to prevent this it may be necessary to cut back the crowding plants every summer. It is quite common in European forests to see patches of land, perhaps four feet square, at twenty-foot intervals, which have been stripped of their mossy cover and sown to seed. These afford a sort of nursery throughout the forest, from which seedlings may be transplanted and on which a number of seed ling plants are left and form a good forest cover. Mound Planting is a term which signifies the planting of trees on mounds or on the surface of the land. This is some- times done on wet lands for the purpose of getting the roots above standing water, and it is a practice which can be followed in the case of several trees that do well upon rather moist soil, although they may die if put at once into standing water when young. Regeneration by Cuttings. There are few trees that can be grown in general practice from cuttings, but it is the best way to start willows, since seedlings of them are generally quite diffi- cult to obtain. Some species of the poplar can also be grown to best advantage in this way. Regeneration by Sprouts and Suckers. Some trees, such as the willow, poplars, oaks, chestnuts and maples renew themselves very readily by sprouts and suckers. Land that is managed on this plan for renewal is termed coppice. With the exception of the willow and possibly one or two other trees, the growth from coppice is not so large as that from seedlings, and it is seldom employed for other purposes than the production of firewood. In order to get the best growth in this way, the trees should be cut close to the ground when they are dormant, and the stumps left highest in the center, so they will tend to shed water and not rot. The advantage of cutting close to the ground is that the sprouts that come out from the trunk soon get roots of their own, which makes them more durable than when they depend entirely upon the old stump roots and they are much less liable to be broken off in high winds. Pollarding consists in cutting back the side branches of a tree, or cutting off the main stem at a few feet from the ground. The branches may be cut off close to the main stem or at a short distance from it, the latter method being preferable. New PRUNING OF FOREST TREES. 69 shoots spring from the cuts, and these are again cut when of suitable size. What has been said in regard to the season and manner of cutting in the previous paragraphs is practically true here. This process is mostly used in the case of willows and poplars to obtain material for basket work, small poles, fuel, etc. Time of Rotation is a term used to indicate the age to which trees are grown. The length of this time will depend on the species and on the conditions. For some species not less than eighty years should be allowed for full maturity, while still others may be successfully worked on a thirty-year rotation period. It is not used in the same sense as in ordinary agri- cultural operations, where it signifies frequent changes of the crop for several years with a view to getting the most out of the soil. Since trees do not impoverish the soil, but improve it, there is no necessity for any such method of rotation in forestry as there is in agriculture. Pruning of Forest Trees is generally an expensive opera- tion and little is required if trees are properly crowded when young, so that they take on an upright form free from side branches. If they are not crowded when young, many side branches are formed, which generally die out when the trees get large enough to shade all the ground. In some cases these dead branches drop quickly to the ground, and in others they remain for years, producing knots and irregularity in the wood formed in the meantime and should be removed. Trees grown in the open retain their lower branches more or less throughout life and they produce in consequence timber of inferior value as compared with trees grown in crowded woods. Large wounds made by cutting off green branches should be covered. It is often desirable to remove dead branches and it is the practice to do so in some of the plantings of Wnite Pine that have been made in New England. It is said that the lum- ber there is so greatly improved by so doing that the operation is a paying one. But under ideal conditions for the develop- ment of timber trees very little is gained by pruning. The Young Growth is Often Injured in ordinary lumber- ing operations by the felling of the trees, which bend them to the ground and often break them. Where special care is desired to protect the young growth it may be desirable to lop off the 70 ELEMENTARY FORESTRY. branches before felling. This is practiced to some extent where forests are very valuable. The Small Dead Twigs on such trees as spruce, and also the shrubbery which may surround them, are often a very val- uable protection against sun-scald. This also protects from drying winds, which would otherwise, perhaps, sweep through the forests and do them injury. Forest trees seldom do best where they are subject to a strong draft of wind around the trunks. While, under some conditions, it may be desirable to remove the dead branches from trees, yet even if it is decided to do this in the interior of the forest, it is generally best to leave the borders without such pruning in order to protect it from drafts. Forest Weed is a term used to signify any growth that may occur in forests which crowds the other growth, and so pre- vents it from developing to the best advantage. It may apply to raspberry bushes, hazel brush, poplars and other similar materials which often come in our forests in the early growth of the plantation; or even to large inferior trees which are in the way of the proper development of the better species. Buta tree may at one period of its growth be of much value in a for- est in producing shade and acting as a nurse tree, while later on in its growth, after its usefulness has been completed, it may be regarded as a weed. Thinning is the most important part of the forester’s art in securing good timber and in reseeding the land. The ideal con- dition in the life of timber trees is to secure a natural crop of seedlings so crowded when young as to increase very rapidly in height and produce slender trunks free from side branches. When this crowding has gone far enough the less valuable and weaker trees should be removed to give the better trees suf- ficient room for their crowns to develop. These remaining trees in the course of a few years will again crowd one another too severely, and this process of removing poorer trees must then be repeated. ‘Then when the final stand of trees is approaching maturity, thinning should be commenced to let in light and air to produce the conditions under which seedlings develop to best advantage. Heavy thinning should be practiced only after very careful IMPROVEMENT CUTTINGS. 71 consideration. Tt is seldom desirable, as it lets in too much sun- light and may encourage a growth of grass. Where natural regeneration is practiced, only such openings should be made as will be shortly covered with valuable species. Important Principles that Should be Remembered: (1) That increase of wood is proportional to leaf surface and therefore the lands should be kept as nearly as possible covered with a canopy of leaves, which should be on trees that are valua- ble for their timber. (2) That leaves need light; therefore partly shaded branches form but little and imperfect wood, and those that are very heavily shaded die out; crowding prevents the formation of branches on trees and is important in securing the best timber. The amount of waste in branchwood varies greatly, it being very much in trees that are entirely open grown, and very little in trees that have been severely crowded. But as over-crowding causes decay it is important to do the thinning as soon as the tree has taken on a proper form. Crowding on one side causes crooks, and these can be prevented by cutting off the crowding tree or branch. Waste in Forests occurs, as has been partially stated, in branchwood, crooks, rot, and in growing of the kinds of trees that are not marketable. The kinds that are marketable depend largely on the demand. In considering this subject it is best to be conservative and to select kinds that are of stable value, and not likely to go out of fashion. Since crowding is best done by small trees among the large timber trees, they should be of a kind that are marketable when small. Much waste in timber is caused by cutting trees when small. The amount of waste in the shafts of straight trees, excluding trunks, branches and bark, may vary from eighty-one per cent in a tree eight inches in diameter and ninety feet high, to six per cent in a tree forty inches in diameter on the stump and one hundred feet high. It will thus be seen that there is great loss from cutting trees when small, especially if they are growing rapidly. Improvement Cuttings is a term used to signify an improvement of forests by cutting out inferior and crowding trees. This is a very important matter in getting almost any forest tract into a condition where it can be managed to best 72 ELEMENTARY FORESTRY. advantage under the group, strip or other systems. Generally it will at first consist in removing the dead, rotten and mature trees and those of inferior species, and so give better oppor- tunity for the more valuable kinds. This is a matter that calls for much good judgment. Care should be exercised not to make openings so large but what they will shortly be occupied by seedlings of valuable trees. Where large openings are made they are apt to become covered with grass, which is a great detriment to any forest growth and always indicates that the cutting has been done too rapidly for best results. The Ax and Saw, then, as will be seen from the foregoing paragraphs, furnish the most important means when used judiciously in securing the best growth of timber in forests of this section and the proper succession of growth on forest land. The Farm Woodlot is a customary feature on many farms in the northeastern states. As a rule it occupies land that is of very little value for any other purpose. It is generally not man- aged at all, but left to look after itself, and often it is pastured. It is expected to furnish firewood, posts and poles and an occa- sional stick of dimension stuff. Too often the best is cut and the poorest left to grow. Under such rough treatment the woodlot becomes stocked with an inferior growth that is of little value ~ except for firewood, and it does not produce as much of that as it might under a different system of management. Improving the Woodlot. The general rules laid down for the management of forests will apply here. The cattle should be kept out, so as to give the young seedlings a chance to grow. Improvement cuttings should be introduced with a view of get- ting rid of the crooked and mature trees and those of inferior species and of encouraging a growth of young seedlings of val- uable kinds, CHAPTER VI. PROPAGATION. Trees are Grown from Seeds or by Division. The latter term includes increase by cuttings, layers, buds and _ grafts. Plants grown from seeds are generally more vigorous and longer lived than those of the same species propagated in any other way. Trees should be grown from seeds when it is prac- ticable to do so, but willows and some other trees are apparent exceptions to this rule and seem to do as well when grown from cuttings as when grown from seeds. Varieties do not generally perpetuate their peculiar characteristics when grown from seeds, and must therefore be propagated by some method of division. The Most Desirable Trees from Which to Propagate are those of good form and healthy growth; the latter is the one most important requisite, especially if new plants are to be grown by any method of division. It is not so essential in selecting seeds, as even weak plants may produce good seed- lings, but unhealthy cuttings, layers or grafts are of very uncer- tain growth. In general, it is best that the stock trees be healthy throughout, but a tree may have a rotten trunk due to some injury and still have perfectly healthy branches and be a desirable tree from which to propagate. SEEDS. Sources of Seeds. In growing trees from seeds the source of the seeds is very important. It may be given as a safe general rule that seeds are most desirable which come from trees grown in as severe a climate as that in which the seeds are to be sown. It has been found that trees of Boxelder and Red Cedar grown from seeds gathered in Missouri are not nearly so hardy in this section as those from seeds grown in our own state. It has also been found that seeds from the western slopes of the Rocky Mountains, where the climate is very humid, produce trees which are not so well adapted to withstanding the condi- -1 ELEMENTARY FORESTRY. tions of this section as trees grown from seeds from the eastern slopes, where the summers are very dry and hot and the winters very dry and cold. Our climate is especially trying to trees, and it is necessary to exercise much more care in the selection of tree seeds here than it is in the more favored climate of the castern and western coast states. There are Conditions Under Which Every Species of Tree Thrives Best and makes its greatest growth, but the trees produced under these conditions are not always the hardiest. As we reach the limits of their growth, trees have a tendency on account of drouth or cold to become smaller, more compact in form and to fruit younger; e. g., the Boxelder is a large tree in Kansas and Missouri, but as it gets towards the Manitoba line we find it becomes dwarfed and more bushy in habit. Towards the southern limit of its range the tree becomes more open in habit and more liable to disease. The Scotch Pine seeds imported into this country are generally saved from the small scrubby trees that are found in the higher altitudes of the mountains of Europe, because such trees produce the most seeds and they are most easily gathered from them, while seeds are seldom gathered from the large timber trees of this species, and it is very likely that this poor seed stock is responsible for much of the scrubby appearance of many Scotch Pine planta- tions in this section. Trees Have a Strong Tendency to Perpetuate Qualities which have been developed in them by climate and soil condi- tions. Hence, even though an essential point in considering the value of any tree is its hardiness, the question of size is impor- tant and should be taken into account, as we generally wish to grow trees of as large size as practicable. We may conclude, then, that since trees from a very cold climate generally lack in hardiness, and those from a very severe climate may lack in size, it is best to procure seeds from the best trees grown near by or from those grown under similar climatic conditions else- where. It is not generally necessary to limit this range very closely, as a hundred miles north or south of a given point will seldom make much difference in hardiness, unless the climatic conditions are very dissimilar. The Place Where the Trees that we ate to Set Out are Grown is not of so great importance as the source of the seeds GERMINATION OF SEEDS. TS from which they are grown; ec. g., seedlings of Red Cedar grown in Missouri from seeds of native Minnesota trees would be safer to plant here than seedlings raised in Minnesota from the seeds of native Missouri trees. Seedling Variations. In our common trees variations are not sufficiently marked but that we think of the trees as coming true from seeds, and yet careful observation will show to any one that each seedling plant is different from neighboring plants of the same species. Sometimes a seedling will occur that pos- sesses especially pleasing or curious characteristics that are very marked and desirable. In such cases the seedling is generally propagated by some method of bud-division and makes a new variety. In this way have originated such highly-esteemed kinds as Wier’s Cut-leaf Maple, which was a chance seedling of the Soft Maple, the Weeping American Elm, Cut-leaf Birch, Weep- ing Mountain Ash, Pyramidal Arborvite, and a host of other kinds that are propagated by bud-division by nurserymen. The person who is on the lookout for these or other variations will have no trouble in finding many that may perhaps be worth naming and propagating. Gathering Seeds. All kinds of seeds should be gathered when ripe. In some cases it is best to pick them from the trees even before they are quite ripe, after which they will ripen if kept dry. Unripe seeds do not keep as well as perfectly ripe seeds. Most kinds of tree seeds are most cheaply gathered from the ground. In some cases this method can be greatly facili- tated by cleaning up the land under the trees so it will be smooth and even. Seeds of some species can often be swept up at little expense from under trees growing along the highway. Germination of Seeds. There are many conditions which affect the germination of seeds: (1) Seeds which are thoroughly ripened before they are gathered produce the best plants. Very immature seeds will very often grow, but the tendency with them is to produce weak plants. (2) Freshly gathered seeds, as a rule, are preferable to old seeds for sowing, and seeds that have never been allowed to become very dry are more likely to grow than those which have been severely dried. This is especially true of most of the kinds of seeds that ripen in early summer, the most of which lose their -l1 ELEMENTARY FORESTRY. vitality very quickly when stored. (3) Some seeds, such as those of the Plum, Cherry and Black Walnut, require severe freezing when moist in order to germinate. (4) Seeds that are covered with water will not generally grow. ‘This is true at least of our northern tree seeds. (5) The seeds of some trees germi- nate at a temperature near freezing, while others require a much higher temperature. (6) After seeds of some plants have become very dry, scalding may aid them in germinating, while with others scalding is injurious. It is sometimes desirable to soak seeds for one or two days in tepid water, and then mix with sand and freeze before sowing. Lindley records that seeds found in raspberry jam grew alter passing through the heat necessary to boil syrup (240 degrees Fahr.) and that seeds of Acacia and Lophantha grew after being boiled five minutes, but our com- mon tree seeds will not stand such treatment. Stratification, as the term is used inthis connection, refers to the storing of seeds mixed with layers of earth, leaves or other material. It is customary to apply the term solely to seeds that are mixed in this way and kept frozen over winter. It is the common practice with the seeds of such trees as the Black Wal- nut, Hickory, Basswood, Plum, Cherry and Mountain Ash. Where only small quantities are to be cared for they are gener- ally mixed in boxes and the boxes buried in well drained soil out of doors, but where large quantities are to be handled they may be mixed with soil on the surface of the ground and left until spring; stch a pile is termed a pit. One of the best materials with which to cover seed pits is inverted grass sod. It is a good plan to have the material that is mixed with the sced so fine that it will easily go through a screen and leave the seeds sep- arated for sowing. Wintering Acorns and Other Nuts in Large Quanti- ties. On account of the great liability to injury where a large amount of nuts are stored in heaps, and on account of the imprac- ticability many times of stratifying them with sand, the following plan is resorted to in some sections: A house is made, preferably with a sandy floor, so as to secure good drainage, and is covered with sod roof and sides, so as to keep out most of the frost. This may be of any size, but perhaps 20 feet in width and any length would be very convenient. The 7 CLASSIFICATION OF SEEDS. 7 nuts are spread over the ground about 18 inches thick, and are kept stirred until frozen in winter. As soon as they thaw out, they are turned once a day. In this way they are prevented from molding, and from the other injuries that are so common to nuts stored in large quantities. It would be desirable to keep the temperature from ever going much below freezing. Seeds May be Classified Into Three Groups: (1) Those that ripen in spring and early summer, (2) deciduous tree seeds that ripen in autumn, and (3) coniferous tree seeds. Seeds that Ripen in Spring and Early Summer should be gathered as soon as ripe, and, with the exception of the Red Elm, sown within a few days or weeks, as they retain their vitality but a short time. (Red Elm seed will not grow until the follow- ing spring). In raising seedlings of this class it is important to have land that will retain its moisture during the summer months or else that which can be conveniently irrigated, since these seeds must often be sown during very hot, dry weather, and as they cannot be covered deeply they are very liable to fail with any but the best conditions. The thousands of seedlings of Cottonwood, Elm and Soft Maple that spring up on the sand bars along our rivers and lake shores show what are the best conditions for these seeds to germinate. Cottonwood Seedlings can be grown by scattering the branches bearing unopened seed pods along rows in moist soil and covering the seed lightly when it falls, but they are of so uncertain growth that most of our nurserymen depend upon the sand bars and lake shores for their supply. Elm, Soft Maple and Mulberry seeds generally grow well on any good moist soil. They should be sown thickly in drills eight inches wide and three feet apart, or in narrow drills. Elm seeds should be covered with about one-half inch of soil, Mulberry with about one-fourth inch and Soft Maple with about one inch. If the weather is dry the soil over the seeds should be well packed, and if the weather continues dry the rows should be watered. Watering, however, is seldom necessary on reten- tive soil if the soil has been properly packed. With proper con- ditions seeds so planted will start quickly and grow rapidly; the Elm will grow from six to eighteen inches and the Soft Maple twelve to twenty-four inches high before the first autumn. Such 8 ELEMENTARY FORESTRY. seedlings are large enough for permanent setting in forest planta- tions or windbreaks. They may be allowed to grow in the seed bed another year without injury, but should be transplanted before the growth of the third season begins. Seeds of Deciduous Trees that Ripen in Autumn may be sown to advantage in the autumn; provided, (1) the soil is not of such a nature as to become too solidly packed over them before spring; (2) they are not liable to dry up or wash out; or (3) they are not subject to injuries from rodents, insects or other animals. In many locations some or all of these possible injuries may make spring sowing most desirable with most kinds of seeds. Our most successful nurserymen, however, prefer to sow in autumn, and try to bring about the conditions that make it successful. In the Matter of Storing Seeds it is difficult to lay down any exact rule to follow, and here, as in all other similar matters, considerable must be left to good judgment. As a rule, how- ever, it is perfectly safe to winter over all of the seeds of hardy plants which ripen in autumn, by burying them in sand out of doors. Tree Seeds that Ripen in Autumn may be divided into four classes, which require different methods of treatment to grow them, viz., dry seeds, seeds with fleshy coverings, nut seeds and leguminous tree seeds. * Dry Seeds, like those of the Ash, Birch, Hard Maple and Boxelder, are very certain to grow when sown in the spring in drills as soon as the soil can be easily worked, in the same way as recommended for Soft Maple and Elm. If not sown until spring they will have to be kept over winter, and when only a small quantity is to be kept over this is best done by spreading the seeds on the surface of the hard ground, covering with an inverted box and digging a ditch around it to carry off the water, or the seeds may be mixed with sand and kept in a dry, cool place. Large quantities may be kept on dry ground under a shed. These seeds will stand considerable drying, but if allowed to become very dry, hot, or moist, their vitality may be injured or destroyed. Seeds with Fleshy Coverings, as those of the Cherry and Pium, should be kept from getting dry before planting. The best way to handle them is to separate them from the pulp, mix with Ne} SEEDS OF CONIFEROUS TREES. v moist sand out of doors, and keep them moist until planted. It is generally safe to sow such seeds in the autumn on good land, but some growers prefer to sow them in the spring. This class of seeds requires to be frozen before germinating. If allowed to get dry before being frozen, they should be mixed with moist sand for a few days until plump, or they may be soaked in water. but care must be taken that they do not get water soaked. Some- times the dry, hard shells of such seeds seem to be waterproof. In this case, if the seeds are of special value, it is a good plan to file a hole through the shell, so as to let the seed become moist. Most seeds of this class grow the first year if properly handled, but some of them—jfor example, the Red Cedar and the Wild Thorn—even with the best management, will remain dormant in the ground for one year before growing. Nut Seeds, as those of the Oak, Hickory and Walnut, should be handled as recommended for seeds with fleshy cover- ings, but are more sensitive about being severely dried. As they do not transplant readily, it is very desirable to plant them where they are to remain permanently. They should be covered about two inches deep. Seeds of Leguminous Trees, as those of the Black Locust, Honey Locust and Coffeetree, will stand severe drying for a long time and still grow, provided they are treated with hot water just before planting. In this case the hot water should be poured over the seeds shortly before they are sown, and be allowed to stand until cool, when it will be tound that some of the seeds have swollen up; these should be picked out, and the remainder be treated again with hot water, and the process repeated until all have swollen. Seedlings of this class generally transplant readily, and are managed in the same way that is here recom- mended for the Ashes and Maples. Seeds of Coniferous Trees, such as Pine, Spruce, Tamarack and Arborvite, are dry and winged, but the Red Cedar has a fleshy, berry-like covering surrounding its seed. The seeds that grow in cones are most easily gathered before being shed from the cones. The cones should be gathered before they open, and then dried, after which those of most species will open, and the seeds can be threshed out. Cones of a few trees, as those of the Jack Pine, will not open without artificial heat. These 80 ELEMENTARY FORESTRY. can be opened by gently heating them over a stove or in an oven to a temperature of from 100 to 150 degrees Fahr. Seeds of this class grow readily when sown, but must be very carefully stored or they will lose their vitality. They should be kept simi- larly to the seed of the Ash and Boxelder, but are more liable to injury than these kinds from too much moisture or heat, and for this reason some careful growers prefer to always keep them mixed with dry sand in a cool shed. The seeds of the Red Cedar hang on the tree all winter, and must be picked by hand. They should be soaked in strong lye for twenty-four hours, the fleshy covering removed by rubbing them against a fine sieve, and then stratified in sand, where they will be frozen during the winter. Even with this treatment they will seldom grow until the second year. Raising Coniferous Trees from Seed. The land selected for sowing the seed should have a light, porous surface soil, preferably underlaid with a moist subsoil that will not dry out easily. It should be so located as to have good circulation of air over it, that the plants may dry om quickly after rains, and it must be so shaded as to keep off about one-half of the sunlight. This latter permits a play of light and shade over the bed all day, and is about the condition under which we find nature rais- ing such seedlings where trees partially shade the ground and protect them from the constant rays of the sun. In practice we aim to secure these conditions as follows: A piece of well drained, rather sandy soil, in an airy place, is selected, and laid out.in beds four feet wide. In May the seeds are sown rather thickly (about three good seeds to a square inch), either broad- cast or in rows, and covered with about one-fourth inch of sandy loam and then with about one-fourth inch of clear sand. Some of the smaller seeds, like those of White Spruce, should not be covered more than one-fourth inch. Before the seedlings break the ground, a framework, six feet above the beds, is made, and covered with laths, laid about one and one-half inches apart, running north and south, or with sufficient brush to shut out about one-half the sunlight. If the bed is very much exposed to the winds it should have similar protection on all sides. In such a place as this, or in woodlands where these conditions can be fulfilled, evergreens can be raised with much certainty, while if planted in the open ground most kinds are sure to fail. RAISING CONIFEROUS TREES. Si The most common cause of failure with those who try to raise evergreens is what is known as “damping off,’ which occurs only while the plants are growing rapidly the first year. In such a case the seeds start well, and the seedlings grow vig- orously for a short time, or until we have a spell of damp weather, and then die off with great rapidity. It seems that the sunlight and the mud that has been spattered on the plants so weaken them that they are liable to disease. For this reason we shade the bed, and cover with sand, which will not allow the mud to be spattered over the seedlings, and in very moist warm weather we occasionally apply dry sand to dry off the plants. Figure 10. Evergreen seed bed shaded with a screen of old brush placed on a frame. For most kinds of conifers the shade is required for at least two years. Coniferous tree seedlings grow very slowly when young, sel- dom making a growth of more than two or three inches the first year. The most rapid growing of our pines seldom produce a growth of more than sixteen inches in four years, and should not be moved to their permanent place until about this time. They should, however, be transplanted from the seed bed to a temporary place when two years old, to prevent crowding and to facilitate root growth. On the approach of winter the beds of coniferous seedlings should be covered with about three inches of straw or leaves, evergreen branches, or other material that will afford protec- tion from the sun and from alternate freezing and thawing. 6 xe ELEMENTARY FORESTRY. This should be removed in the spring after all danger from dry- ing cold winds has passed. Depth to Cover Seeds. Most of our tree seeds should, in good soil, be covered from one-half to three-quarters of an inch; but this is rather too much for such small seeds as the Birch, Alder and Cottonwood, while the Black Walnut, Native Plum, Acorns and other large seeds and seeds of Boxelder, Ash, Soft Maple and Basswood may often be covered two inches to advantage if the soil is somewhat dry. It is a good rule not to cover any tree seeds deeper than is necessary to secure permanent moisture, and on wet or heavy land only a very thin covering is desirable. If the land is very heavy, it is a good plan not only to cover lightly but to sow more thickly than usual, as a large number of seeds may be able to push up through the surface soil when a few would fail to do this. The Amount of Seeds of Deciduous Trees to Sow on a given area depends very much on the kind and quality of the seeds and the soil in which they are to be sown. As a rule, thick is better than thin sowing. The seeds of Boxelder, Ash and Maple should be sown at the rate of about one good seed to the square inch; Elm and Birch should be sown twice as thick. Plums and cherries sown in drills should be allowed about one inch of row for each good seed. Black Walnut, But- ternut, Hickory and similar seeds should preferably be planted three or four in a place, and all but one seedling cut out when nicely started. If sown in drills they should be placed from three to six inches apart. Rather thick seeding does not seem to be any hindrance to the making of a good growth by seed- lings of most of our broad-leaved trees the first year, but if left thick in the seed bed the second year they are often seriously stunted. On this account such seedlings should be transplanted or thinned out before the beginning of the second year. In nursery planting it is a good plan to sow in freshly stirred land, as the seeds are far more likely to get a good start in it than in soil that has remained untilled long enough to become crusty and lumpy. ‘Then, if the seeds are planted immediately after cultivation has been given, and while the soil is still moist, they have at least as good a chance as the weeds to start, while oth- erwise the weeds are soon ahead of the seedlings. , It is important to keep the soil loose and mellow between HEIGHT OF ONE-YEAR SEEDLINGS. 83 the seedlings, and to keep the weeds very carefully removed until at least the middle of July, after which they may sometimes -be left to advantage to afford winter protection; but in the case of very small seedlings this protection is best given by a light mulch, put on in autumn and taken off in spring, and the weeds should be kept out. If the seeds of Red Cedar, the Thorn, Mountain Ash, and other seeds that require a long time to start, are sown in the spring, and do not germinate, it is a good plan to cover the bed with about an inch or two of hay or leaves, keep out weeds, and let this mulch remain until the following spring, when the seeds will probably be in condition to grow, and the mulch should then be removed. TABLE SHOWING THE APPROXIMATE HEIGHTS OF ONE-YEAR OLD SEEDLINGS GROWN ON GOOD AVERAGE SOIL IN MINNESOTA. Height in BOTANICAL NAMES. COMMON NAMES. Taches: PUNRUS: SUR ODUSIns wv Gesainn dha, Le edaOS WHILE Pines sesnuscreriacs 3 PUNUS LEB: wean nse ase saciian oe 150K Western White Pine 3 PURUS FESTHOS Bio. i.3 six hewn wees AAU COTY Red) Pines va avs akan eee 3 | PINUS GTUATICGIA: setiisss Seda Easy SOc | JACK PING crysis access 3 Pinus ponderosa scopulovrum 2.0.1.0... ROCK PING .tayaruenianneses | 3 PURAUS SYLDESIVAS 8 ass mnccamanns aamasteats mes Sootehy Pinekcs ssschans sx ais 3 Pinus laricio austvtacd...... 0.6.0 e eee | Austrian Pine ......... 3 Larvtx lavtctnd ...... 0.002. esis Rare eA TRAC Kee suerstacsregianoasies,o5 te 3 LOVEE CUV OPED: Sovie d nsastn ARR RE SLES European Jarch .......... | 3 PiCOd CANGDAEW STS « sccissisisaieieidueds sia;a 50008 58.568 SW lnit]e:S pruces iio asics ates 2 PPLCEO METIGN GD: sv seostss eeths Sandon 8 eee Black Spruce.............. 2 Picea pungens ........ ie eens ei aeeintey || DIMES DRUG, Zasaicagtusen tae | 3 Picea engelmannt............0++.......| Engelmann Spruce....... 3 PUCOC CRC Garg tare sie) /etyalen rin .....| Norway Spruce........... 2 TSUGE.CONADDENSES: scsi, ve oad es Bh Sass Hero taisa sacie sans sansa 3 Pseudolsuga tavtfolid.........ee cece Douglas Spruce........... 4 AGES: CAUSA MED ive 54 5 shais.5 wasETR wRAOR, Balsam Pires cicewascseaes 3 Abtes concolor .......... fetes | White Fir ..... CRaaaiayatell 2, S4 TABLE SHOWING THE APPROXIMATE HEIGHTS OF OLD SEEDLINGS GROWN ON GOOD AVERAGE IN MINNESOTA. (Continued.) ELEMENTARY FORESTRY. ONE-YEAR SOIL 30TANICAL NAMES, COMMON NAMES. TWO OCCLAERIAIIS: sins th soa veers Patna SUNTPCVUS VIVETNIANGA co.cc cece cee ee SUNTPEVUS COMMUNTS coc c cr creccereceee Juglans nigra Juglans cinerea Hicorta ovata FLUCOVIA MINTMA. 0... eevee Salix nigra Salix anivgdalotdes ..... 6... SALTED OLS. aun sg sis tienes ss sarin RaeemiR TRE SQMH TUCIAG: 2 <5 can aoe le ne o585 Popilus lremulotdes occ. ccc cece cee ee Populus grandidenta vec. ceee cree. Populus balsamtfera ......... Populus deltoides Betula PAPVVI HE: x2 icisased sac ek De Betula alba Fetula lutea Ostrya virginiana Carpinus caroliniana OUEF CUS AIDE icin ek, cone bese ees eee Quercus macrocarpa Quercus rubra Quercus coccinea CHiRUS CHLETICA WE jie, DSR Hawes oeA CLUS ROGCEMLOS Diris sir Fe nakews ye sea temtenesnre CIMUS PUbeSCOHS. . 6. cee CELLS O6CLUENLETIS nc siriee wenn owen en peae Morus rubra .... Height in Inches. Arborvitx Red Cedar.... Cominon Juniper Black Walntit..cc.4 20. .cu4l Butternut... Shellbark Hickory Bitternut Hickory Black Willow Peachleaf Willow White Willow Shining Willow.. .... Aspen Largetooth Poplar Balsam Poplar . Cottonwood Canoe Birch.... European White Birch .. Yellow Birch Hop Hornbeam . Blue Beach White: Oak ..< tac. ceeeaces, Bur Oak Red Oak Scarlet Oak cei see: White Elm Cork Blmtccsee. sie ieee: Slippery Elm Hackberry Red Mulberry............. F = ne o HEIGHT OF ONE-YEAR SEEDLINGS. 85 TABLE SHOWING THE APPROXIMATE HEIGHTS OF ONE-YEAR OLD SEEDLINGS GROWN ON GOOD AVERAGE SOIL IN MINNESOTA. (Continued.) BOTANICAL NAMES. Morus alba tartarica PY TUS TLOCUSIS ocriind wie ta ty te Cy ABR Seuss PYPUS AMETICENG 24.0.0 cena eens Pyrus sambuctfolta Amelanchter CANAACHSIS. ccc cee cece ee Crataegus tomentosa . Prunus americana Prunus pennsvivanica. . Prunus serotina Prunus virginiana Gledttsta tvtacanthos 6.2... cece eee eee Gymnocladus diotcus Robinia pseudacacta........ A COV SOCCHAT UM 1a siieisindcatanionsits RAGS Acer PIGIENO1EOSs 225 asc icdens Sanaaxweds Acer rubrum Acer saccharinum cer pennsylvanicum ACEF LAHLAPICUNT waaes acuees 955 Acer negundo wEsculus hippocastanum .... PEE SCULUS HE LADIES seas mie estas HOR He Rhamnus catharticus LUO ON UAV TCA id o.4 dale niard ns o5 MEIN eee ELlacagnus augustifolia FYAXINUS AMEVICAN|A . 6.66. cece eee eee Fraxtnus lanceolata...... Fraxtnus nigra Catalpa speciosa VP EDUF NITE TECHIE LO shih a £5 ts eisesed Sagear ohne COMMON NAMES. Russian Mulberry Wald ‘Gratin tees ac anid American Mountain Ash . Elderleaf Mountain Ash.. Juneberry Black Thorn Wild Plum Wild Red Cherry Wild Black Cherry Choke Cherry ...: 0. ss. o:%e2. Honey Locust Come etreessious axis onal TOCUSE «2.04 due Sugar Maple Norway Maple............ Red Maple Soft Maple Striped Maple............. ‘Tartarian Maple BOKE1AED wird. aheynessined Horse Chestnut Ohio Buckeye............. Buckthorn Basswood Russian Olive White Ash Green ASN... senwssses: Black Ash.. .. Hardy Catalpa........... Black Haw.............. Height in Inches. SG ELEMENTARY FORESTRY. CUTTINGS. Cuttings are pieces of the branches or roots which have the power of growing and forming new plants when placed in moist sand, soil or other material. For example, the pieces of the twigs on branches of many kinds of willows and poplars, when taken while the tree is dormant, will root when placed in moist soil, but there are few other trees that grow as readily from cut- tings as these. Cuttings of the roots of many kinds of trees, as the White Poplar, Wild Plum, Yellow Locust, and many others that sprout from the roots, will grow if treated about the same way as branch cuttings. In growing trees from cuttings the source of the cuttings is not of so great importance as the source of the seed from which the stock trees were grown, for the qualities of individual trees are probably not permanently or greatly changed by climate. For instance, trees grown from the cuttings of Russian Poplars would be as hardy in Minnesota if the cuttings came from St. Louis, where they had been growing for years, as they would be if imported direct from Siberia. However, owing to a longer growing season at St. Louis, the wood might be of a more open texture, and perhaps might not resist cold as well as Minnesota- grown wood; but after one season’s growth in Minnesota it would probably be as hardy. The same would hold true of plants propagated by any method of division. With the excep- tion of Willows and Poplars, very few of our ornamental trees grow readily from cuttings. The best time to make cuttings is in the fall, as soon as the leaves will strip easily from the twigs. Most of the willows and poplars will grow readily from cuttings made in the spring, and even those made in summer will gener- ally grow if planted in moist soil. For this purpose the smaller branches with the leaves removed should be used. They may also be rooted from growing twigs with the leaves left on, pro- vided the cut surfaces are placed in water, as they would be if stuck in the soil of a swamp or treated the same as cuttings of geraniums. These latter ways, however, are not to be depended upon for general propagation purposes. The Form and Size of Cuttings is a matter upon which there is great difference of opinion. Cuttings of the Willow from one bud each and only an inch or two long up to those a PROPAGATION BY CUTTINGS. 87 foot or more in diameter and ten or twelve feet in length can generally be made to grow, but probably the most convenient size for general planting is one-half inch in diameter and twelve inches in length. They are generally tied in bunches of 100 or 200 each for convenience in handling, and care should be taken to keep all the butt ends one way to facilitate planting. Very large cuttings are liable to decay in the center, and are not best to use, although they often make a very rapid growth. Poles of willows and poplars are some- times laid in furrows where they will gen- erally sprout wherever the bark is laid bare and often make good trees. In Planting Cuttings of ordinary size it is a good plan to have the soil loose, and then, after marking off the rows, the cuttings can be pushed into the land the proper depth. If not desirable to plow all the land, it may be loosened just where the rows are to come. Where a subsoil plow can be obtained, it can be made very Figure rr A bunch useful for this purpose. of willow cuttings. Cuttings should be planted at an angle of about forty-five degrees, leaving only one bud above the sur- face of the ground and the soil should be packed firmly around Figure 12. Planted cuttings, showing angle and depth at which to plant cuttings. them. Those set in a slanting position settle with the soil and remain firm, while those set vertically mav become loosened by the settling of the soil near them, leaving too much of them exposed above the surface, unless very great care is exercised in planting. The rows in the nursery should be about four feet apart, and the cuttings about six inches apart in the rows, though 88 ELEMENTARY FORESTRY. a much less distance may sometimes be sufficient. In packing the soil over the cuttings great pains should be taken to get it very solid around the lower end, and if the soil is very dry, the firmest pressure of the full weight of a man over the base of each cutting is not too great; in fact, when the soil is dry it cannot be made too firm over the cutting. When the soil is moist, how- ever, only enough pressure should be used to bring the par- ticles in close contact and close up the air spaces. The Cultivation of Cuttings should commence shortly after they are planted, and the top soil should be kept loosened to the depth of about three inches, which, while not disturbing the solid soil around the base of the cuttings, prevents evapora- tion from the soil. Time of Planting Cuttings. Spring cuttings may be planted at once where they are to grow. Autumn cuttings may be planted out at once, provided the land is not wet, but when planted at this season they should be covered with soil turned toward them with a plow. In the spring this covering should be raked off before the buds swell. The ground being warm in autumn often causes autumn-planted cuttings of some kinds to root before cold weather sets in, and if made up before the first of October they may thus score quite a gain over spring-planted cuttings. If not desirable to plant in the autumn, the bundles of cuttings may be kept over winter, buried in moist soil, prefer- ably that which is somewhat sandy, where there is no standing water; but much care should be taken to keep them from dry- ing out. To this end the bundles should be buried so as not to touch each other, and have two or three inches of soil packed in between them. If they are kept in a cellar, moist sawdust will be found to be good material to keep them in. The amount of growth made by cuttings varies much, accord- ing to the kind of plant, size of cuttings, soil, etc. The most of our willows will make a growth of three or four feet, on good soil, in one season, from ordinary cuttings. The Solar Pit. There are many trees that will not grow from cuttings unless they have their roots started a little before planting. This is most easily accomplished by means of what is called the “solar pit,” which owes its success to the fact that cut- tings root first at the warmer end. It is made and used as fol- LAYERS. so lows: The bundles of cuttings are heeled in as recommended. In the spring they are taken out, and buried close together, with the butt ends uppermost, in a warm sunny spot, and covered with about six inches of soil. A hotbed frame, with sash, is then put over the spot, to warm the soil. Sometimes, instead of using sash, the soil over the cut- tings is covered with a foot or more of fermenting manure. In either case the soil is warmed, and the formation of roots encouraged. In using the solar Figure 13. The solar pit, 3 z showing bundles of cuttings pit the rooting process should in place under glass. not be carried so far as to permit roots to show plainly, as they are liable to be broken off in planting out; but the cuttings should be planted out as soon as they show signs of healing over on the butt end. This healing- over process is called callousing, and in many plants neces- sarily precedes the formation of roots. LAYERS. Layers are portions of the branches of trees, shrubs or vines which are covered with earth without being separated from the parent plant and there take root and grow. These are cut off from the main plant in autumn or spring, and form new plants. Almost all trees and other plants can be rooted in this way, but, while some root very easily, others require so long a time to do so as to make it impracticable with them. The growing of trees from layers is seldom practiced in this country, but in some European nurseries it is a common means by which to increase special varieties of trees. For this purpose what is commonly known as mound layering is often used. This consists simply of drawing the soil up around the sprouts that come from the stump of a tree, covering the base of them about a foot in depth. It may be done at any time of the year after the sprouts are two or more feet high, but preferably in the spring. After the sprouts have become well rooted they may be removed in spring or autumn and treated the same as seedlings. Layering is sometimes practiced in European forests to fill up vacancies, and a similar method is often employed in nurseries. 90 ELEMENTARY FORESTRY. GRAFTAGE. Graftage refers to the growing of one plant on the stem, root or branch of another plant. There are several forms of graftage, which are generally known as grafting, budding and inarching. It is a common practice to use graftage in the growing of the different varieties of fruit trees, and it is also used to some extent in the growing of some of the varieties of ornamental trees that cannot be grown from seed. ‘Trees that are grown by any form of graftage are seldom as long-lived as those grown on their own roots, and these methods should be avoided when it is practicable to do so. These methods are not much used in common practice, and consequently are not discussed at length here. Inarching is a rather unusual way of growing plants. It works on the principle that when the growing stems, branches and roots of the same or closely allied plants are held closely together for some time they become united. Such unions of roots are frequently found in woodlands; in some cases the roots of the same trees, and in others the roots of different trees, become grown together. Occasionally also trees are found erown together by their branches or stems. Inarching is some- times used for growing the Cutleaf Birch, in which case the sprouts from a stump of a Cutleaf Birch, or the twigs from a small tree laid on the ground, are tied to small Birch seedlings, which have been grown in pots and plunged to their rims in the ground near the tree. In doing this the bark is removed for about two inches at the point of contact of the twig and seed- ling, which are then tied firmly together. It should be done by the middle of June, but will often be successful if done even a month later. They should be kept together until the leaves fall, and then the branches from the parent tree should be cut away, leaving the seedlings with the twigs grown fast to them. These should be carefully heeled-in over winter, and in the spring the seedlings should be cut off just above the union, so as to throw all their strength into the adopted twig of the Cutleaf Birch. This method may also be used to replace lost branches on trees or vines. CHAPTER VII. NURSERY PRACTICE. Nursery. This term is applied to a plot of land used for raising plants that are intended for planting elsewhere for their final growth. Soil and Cultivation. The best soil for a general nursery is a deep, rich, reasonably level, retentive upland. It is cus- tomary to grow most of the nursery crops in rows, so that they may be readily cultivated. The land should be plowed deeply when the crop is planted, and the surface soil kept loose and fine during all the early part of the growing season, or until about the middle of July. If the land that has to be used for a nursery is rather shallow, it should be gradually deepened by plowing from year to year, and, if inclined to dry out, the addi- tion of large quantities of organic matter, together with constant cultivation, will do much to remedy these defects. The cultivation of a nursery or young forest plantation, pro- vided the latter is planted in rows, should consist in keeping the land stirred to the depth of three inches, thus giving a dust blanket, which will protect from drouth. After the first of August much cultivation is likely to encourage a late autumn growth, which should be avoided; but a moderate quantity of buckwheat or oats may be sown then, and be allowed to grow the remainder of the season, to serve as a winter protection—to hold snows, and prevent the heaving out of the young seedlings . by frost. GRADES OF NURSERY STOCK. Nursery stock of different kinds has come to be known by such convenient names as seedlings, transplants, street trees, for- est-pulled seedlings, etc. 92 ELEMENTARY FORESTERY. Seedlings are young plants, grown from seed, that have never been transplanted, and are generally designated by their size or Figure 14. A bunch of Green Ash Seedlings. age. They form the cheapest class of nursery stock, and are used largely for starting windbreaks. Transplants are seedlings that have been at Ieast once trans- planted, and are designated by the size and number of times they have been moved. They are higher in price than seedlings, but with some kinds of trees they are much more likely to grow, and may be well worth the extra price. Evergreens, especially pines, will seldom do well unless once transplanted before being set in a permanent place. Street Trees include the trees of large size which are used for street, shade and ornamental purposes. ‘To be of the best quality they should have been transplanted two or more times and have received some attention in the way of pruning so as to give them a good form. Such trees vary much in quality and price, but the best are necessarily rather expensive. Forest-pulled Deciduous Trees of small size can often be obtained at a very low price, and may be as desirable as those that are nursery grown. Forest-pulled Evergreen Seedlings may also be desirable, but too often they have poor roots, or have been so injured by poor handling that they are generally worthless. Forest-pulled Shade Trees sometimes grow very well, but they are always inferior to good nursery-grown trees. ‘They are greatly improved by having their roots shortened two years before they are to be removed, and when so treated grow very well. TRANSPLANTING. Transplanting is Simply the Removal of the Plant. It may be to some permanent place, as a park, lawn, or street, or it may be done for the purpose of improving the root system, TRANSPLANTING. 95 and to give the tree more room to grow. By shortening the long roots the root system is made more compact and better able to withstand subsequent removal. This may be done by transplanting, or by cutting around the tree with a spade or tree digger. It is especially desirable to do this to trees that are not easily moved on account of their long branching roots, such as the Birch, or to those that have tap roots, like the Oak and Walnut. It is on account of their having had their roots short- ened so they can all be moved with the tree that nursery-grown trees are generally superior to others. In Transplanting it is Important to take up a sufficient amount of roots to support the plant, and as a rule the more roots the better the conditions for growth. Very long roots Figure 15. Extra good roots on a forest- grown Elm, used as a street tree. should be shortened unless the tree is removed to a permanent place, in which case all the good roots should be left on the tree. All bruised or broken roots should be cut off in either case, and the top of the tree shortened to correspond. In transplanting trees they should be set one or two inches lower than they for- merly stood, and the roots should be spread out in the holes without crowding. It is customary to plant many kinds of small trees in furrows made with a plow. Very Large Trees (those over six inches in diameter) are sometimes successfully planted in winter, by taking them up with a ball of earth. This is done by digging a trench around the tree, late in the autumn, deep enough to cut most of the 94 ELEMENTARY FORESTRY. roots, but far enough away from the tree to leave a large ball of earth. The trench is then filled in with a mulch of some kind, and when the ground is frozen the tree is moved, with the ball of earth attached, to the hole which has been previously prepared and kept free from frost. After Trees Have Been Moved, or had their roots short- ened.in some other way, they should generally not be transplanted again for at least one or two years, during which time they will have overcome the injuries done to their root system. The time which should thus elapse will vary with the kind of tree, and also with the amount of injury done. Where the injury is severe a much longer time will be required for recovery than where it is slight. Time to Transplant. Planting of trees should always be done when they are dormant, or just as they start into growth in the spring, which is generally from the middle to last of April. If for any reason it is desirable to risk the moving of trees late in the spring, after the leaves have started, they should be cut back severely, all the leaves removed, and great pains be taken to secure all the roots and to prevent their drying out. Very hardy deciduous trees, as the Elm, Cottonwood, Boxelder and Ash, can often be successfully moved in the fall, if the ground is moist at the time of removal, but great care must be taken to work the soil in very compactly between the roots, so that there will be no large air spaces among them. If the trees are large, it is a good plan to stake them, so they cannot be blown about by the wind. The more tender trees should not be transplanted in this section in autumn, and even the hardiest kinds should never be moved at this season unless the soil is moist. Transplanting Evergreens. When seedling evergreens are two years old they should be transplanted, and this should be done about once in three years afterwards, until they are moved to their permanent places. As evergreens are very sensitive to being moved, this requires more care than with most deciduous trees. The most important point is to not allow the roots to have even the appearance of being dry. They may be trans- planted in the spring, as soon as the ground works easily and the roots have white tips, and they may be safely transplanted even up to the time that the new growth shows about an inch, but at TRANSPLANTING. 95 this late time more care must be taken in doing the work than when it is done earlier. Ivergreens can sometimes be moved successiully in August, or even in the autumn, if they are to be carried only a short distance and the conditions of the weather and land are favorable; but this is not a time for general plant- ing, and it is seldom advisable to do it at this season. The Very General Error is Current that June is the best time to plant out evergreens. ‘They may be transplanted at this season successfully if the conditions are just right in every par- ticular, but they are much more liable to failure than when the work is done earlier in the season. At whatever time of the year evergreens are to be moved, the- work should be done in such a manner as to protect the roots from having even the appearance of being dry, for if dried ever so little the probabili- ties of their living are much lessened. The kind of treatment that would be considered all right for apple trees might be fatal to evergreens, as they are much more susceptible to injury from drying. In addition to the above precautions to be taken when mov- ing evergreens, it is desirable to shorten back the limbs about one-third, to compensate for the loss of roots. Of course this shortening should not be done in such a way as to disfigure the tree, but, when the roots are in any way severely mutilated, the whole top makes more of a draft on them for moisture than the roots can supply. This pruning is not so necessary in the case of young seedling evergreens or nursery-grown trees that have been recently transplanted, for when they are moved their root systems are not seriously injured. Very Small Evergreens and Other Small Plants are often set in trenches made with a spade, as shown in figure 16. For this method the soil must be loose, and yet sufficiently com- pact so that it can be cut with a spade and not crumble before the plants can be set out. The beds are made about six feet wide, and a board of this length and six inches wide should be used. The soil is thrown out with a spade (A) to the depth of about six inches, but no wider than necessary to just take in the roots. The plants are then placed in position by hand, and a little soil pushed against them to hold them in place. (B) The trench is then half filled and the soil firmly compacted by the feet. The remainder of the soil is then put in and leveled off, the D6 ELEMENTARY FORESTRY. board is changed to the other side of the row first planted and the planting is continued in the same way. (C and D) Such close planting as this is only desirable when it is intended to give special care to the plants, as by shading or watering. Plants should not remain more than two or three years in so close a bed before they are transplanted. When it is desirable to set out small seedlings in rows, instead of beds, a tight line may be used in place of the board. Heeling in. This term is applied to the temporary covering of the roots of trees with earth to keep them from drying out after they are dug and until they are planted. If they are to be kept for only a few days, comparatively little care is needed in Figure 16. Successive steps in planting young evergreen or other very small seedlings. (a) Board in place and trench partly opened. (b) Seedlings in place and partly covered. (c) New trench partly opened. (d) New trench with seedlings in place. covering; but if they are to be kept for several weeks, or over winter, especially if the weather is dry, great care must be taken to work the fine soil in among the roots and to pack it solid. A good way of doing this is as follows: Select a dry, mellow piece of ground, and dig a trench just large enough to take in the roots of the trees when laid close together in a single row. Place the trees or seedlings in this trench. in an upright position, afew at a time, and cover the roots firmly and deeply with soi taken from close in front of the first trench, thus making a trench for the next row. In this section, if Maples, Cherries and other trees not of the greatest hardiness are to remain heeled in all winter, it is a good plan to bend the tops down and cover with PRUNING. ot earth. ‘This is only necessary for winter protection. The neglect to properly heel in nursery stock as soon as it is received is undoubtedly a frequent cause of failure. Trees and cuttings will sometimes get so dry in shipment that the bark shrivels. In such cases the best treatment is to Figure 17. Heeling-in. Various stages of the operation: Row of trees with roots covered; row bent down and the tops covered. bury them entirely for a few days, which will often enable them to recover, Soaking in water will answer the same purpose, but unless very carefully done is likely to injure the wood. PRUNING. Pruning should be avoided as much as possible, and yet be done sufficiently to secure the effect desired. If it is begun early in the life of a tree no large branches need ever be removed, the most desirable pruning being the directing of the growth by pinching off the buds that would develop into undesirable branches; but this is impracticable on a large scale, and for this reason, in ordinary practice, it is often necessary to do more extensive pruning, The Purpose in Pruning Trees is to give them forms that are desirable for the purpose intended. For example, a tree for the lawn or windbreak may be most desirable when covered with branches even down to the ground, while street trees should have a trunk free from branches for eight or ten feet from the ground. Many of the evergreens, and some other trees used for 7 98 ELEMENTARY FORESTRY. ornament, naturally take on so regular and desirable a form that it is not necessary to prune them, except perhaps to pinch or cut off an extra leading shoot that is likely to make a forked top, while the White Iilm, Soft Maple, and others need occasional pruning to remove or shorten awkward branches, at least while the tree is young and growing rapidly. The Proper Time for Pruning is determined by the effect of the operation upon the health of the tree. Dead branches may be safely removed at any season. The removal of live branches during the growing season lessens the leaf sur- face, and hence checks growth. Pruning when the tree is dor- mant results in a more vigorous growth in the remaining branches. Wounds made by pruning just as trees are starting into growth do not heal over as readily as those made earlier in the spring, or during the period of active growth in June. Wounds made in autumn or early winter generally heal over well, but are more likely to cause bad injuries than if made at the close of the winter. These considerations and practical expe- rience have brought about the following conclusions as to the best time for pruning: Large Branches are Most Safely Removed during the latter part of winter, before growth starts. Small branches may be safely removed at this time, or during the growing season, preferably about the middle of June; but such very hardy trees as the Elm, Ash, Boxelder, White Willow and Cottonwood -may be safely pruned at any time in autumn, winter or spring, while the Mountain Ash, Apple, Plum and Wild Cherry are lia- ble to injury if pruned at any but the most favorable seasons. Among the Directions to be Followed in Good Prun- ing are the following: (1) Do not cut off a single branch unless you have a good idea of what you wish to accomplish and the probable effect of so doing on the tree; better not prune at all than to do it without considering the consequences. (2) Avoid doing very much pruning at one time, especially on small street trees, which, if they have all their branches removed from the trunks to their final height, are likely to make too much growth at the top for the trunk to support well in high winds. A better way is to remove a part of the lower branches and PRUNING, 99 shorten back in summer those that are to be removed later; by such treatment a large part of the strength of the tree goes into the top without increasing the size of the lower branches, which may be removed in a year or two without injury to the tree. (3) After pruning paint the wounds with good white lead paint, to keep the wood from decaying and the injuries from thus becoming permanent. This is not so necessary on very hardy trees as on those that are somewhat tender. (4) Where branches rub together it is generally best to remove one of them. (5) Where bad crotches are being formed by the develop- ment of two leaders, severely check the growth of one of them by shortening it, thus throwing more sap into the other and making it the leading shoot. (6) Prevent the formation of long side branches by shorten- ing those that are liable to become too long. This is especially desirable with the Soft Maple, which has a tendency to form long branches that are likely to break off unless occasionally pruned. (7) Where trees have lost their leaders, prune so as to develop one of the side branches into a leading shoot. This the tree always attempts to do itself, but a little judicious pruning will greatly aid it. (8) Every species of tree and shrub has its own natural form, and in pruning do not try to make all of them of one shape. Study the natural form of each kind of tree, and encour- age the development of this form. (9) When trees are full of frost the wood cracks very easily; therefore do not prune in very cold weather, for bad wounds may then be easily formed. Treatment of Crooked Trees. It is common to have some trees in the nursery that are of vigorous, healthy growth, but so crooked as to be nearly worthless. The proper treatment for most of our shade trees when in this condition in the nursery, if anything is to be made of them, is to cut them off at the sur- face of the ground, early in the spring, and then select one of the good, strong sprouts that come from the roots of each tree, train it into a straight stem, and cut away the others. Treated in this way well-formed trees may soon be grown. Such treatment may also be desirable with small street trees that have their stems 100 ELEMENTARY FORESTRY. hopelessly injured. However, trees that to the novice may seem hopelessly crooked may only have crooks in them that will be outgrown in a few years. STREET TREES. Success with Street Trees'is perhaps more dependent on good soil about the roots than on any other one factor. If the land is so very sandy or gravelly as to be subject to drouth, at least two cubic yards (two full two-horse loads) should be taken from where each tree is to be planted and the same amount of good clay or loam substituted for it. If in subsequent years the trees outgrow the limits of the material supplied, more of it should be added, and if this consists largely of stable manure, so much the better, provided it does not come into contact with the roots of the trees. It is important to do this work thor- oughly, for one tree well planted is better than a dozen poorly set out. Kinds of Trees. The best trees for street planting in this section are the White Elm, Hackberry, Green Ash, Basswood, Boxelder and Soft Maple. All of these trees do well in good soil, and with the exception of the Soft Maple they all do well in rather inferior land. Evergreens may sometimes be used to advantage along narrow drives, but they are seldom desirable as street trees. The trees planted should be about two to four inches in diameter near the ground, eight or ten feet high, and of thrifty growth. Much larger trees are sometimes set out, but it is not advisable, as a rule, to plant those that are over four inches in diameter. Smaller trees are often planted and do well if properly cared for, but need more attention in directing their growth than those that are larger. But small, thrifty trees are much better for street planting than large stunted trees. In all cases it is more important to have plenty of good roots than a large top, as a top can soon be developed if the roots are good. Distance Apart. The distance between trees depends on the kind planted and the quality of the land. On rich land in this section the trees named should be put forty feet apart, in fairly good soil about thirty feet, and in poor soil twenty feet apart. This gives sufficient room for good development, but where a quick effect is wanted it is a good plan to set the trees STREET TREES. 101 much thicker than this, and use Cottonwood, Willow or similar fast-growing trees to alternate with one of the kinds named as desirable, with the expectation of cutting out the less valuable when it shall have commenced to crowd the more desirable kinds. Planting. Provided the soil is in the proper condition, the next consideration is the proper planting of the tree. The prep- aration for this should consist in digging a hole of sufficient size to take in the roots without crowding. If the subsoil is very .solid clay, it should be thoroughly loosened up, and where prac- ticable it is a good plan to dig a trench to the loose soil over a water pipe or sewer, for by this means the roots get into loose soil, and drainage is secure, which is often much needed on such ‘and. Sometimes a very stiff hardpan can be broken up to advantage by exploding a small dynamite cartridge in a deep hole made with a crowbar. Before Setting the trec, it should have all broken and dead roots cut off. It should then be set an inch or two deeper than it had been growing, the discoloration above the roots indi- cating the depth at which it had stood. If, however, good drain- age cannot be secured, the tree can be planted less deeply, and then have a mound made around it. Fill in about the roots slowly, being careful (should the tree have a great number of fibrous roots) to work the earth well in among them and under the butt of the tree. Fine soil, free from large stones, should be used for this purpose. Pack the soil in firmly, if reasonably dry, with the heels, or, better still, with a rammer, making it as solid as possible around the roots. The object in doing this is to leave no air spaces about them. It is not a good plan to put water into the hole before the tree is set, but it may be put in when the roots are just covered and allowed to soak away before the remaining soil is put in. Asa rule, however, little is gained by watering if the trees have not leafed out and the moist soil is packed firmly around the roots. Water is most needed after growth starts. Mulching. Newly planted street trees are much helped by a mulch of straw, hay or well-rotted manure. The latter is best, as it also furnishes plant food, but hot manure is liable to injure the trunk if piled against it. These materials prevent the soil 102 ELEMENTARY FORESTRY. from drying out, and this is especially beneficial if the trees are artificially watered. Watering should be done thoroughly or not at all. One good watering should keep the ground moist for two or three weeks, in the driest weather we have, if the land is heavily mulched when the water is applied. For a good watering in a dry time about one barrel of water should be given to each street or lawn tree. A hollow should be made around the tree and covered with mulch before the water is applied. This same amount of water might be applied at the rate of one or two pail- fuls a day, and not be of the least benefit to the tree, if applied to the bare surface of the ground. Figure 18. Soft Maple Figure 19. Soft Maple Figure 20. Soft Maple not pruned since it was once pruned showing several times pruned planted out. Liable to close head that is not preserving a main cen- break in its crotches at liable to break down. A tralaxis. A good form. any time. A bad form. good form. The Pruning of Street Trees at the time they are set out is an important matter. If the trees are very tall and slen- der, it is a good plan to cut them off at about ten feet from the ground, and trim off all side branches, ag shown in figure 21. For trees that have been pulled from the woods this is generally the best treatment, while for nursery-grown trees that have had plenty of room to develop a good top it may sometimes be best to trim so as to leave part of the top. If the trees are trimmed to bare poles before planting, some little pruning will be STREET TREES. 103 required cach season for a number of years to develop good tops, while if they had well formed tops in the nursery and were Figure 21. Elm street tree properly trimmed for planting out. shortened back at planting time much less attention will be necessary. In a row of Elms or other trees there will often be found peculiar individual shapes. Some of the trees will take on desirable forms, while others will be spreading and awkward, and perhaps have a tendency to crack in the branches. In some cases a little extra pruning will bring such unfortunates into shape, but often they are incorrigible, and are best replaced by other trees with better forms. Protection should always be given street trees as soon as they are set out, and this should consist of something that will pro- tect them from sun-scald, gnawing of horses and whittling by thoughtless boys. A good temporary cover is afforded by wrapping the trunk with gunny sacking or similar material, but a more desirable protection is afforded by a slatted wooden frame or box for each tree, CHAPTER VIII. FOREST PROTECTION. INJURIES TO TREES. The causes of injury to tree growth are many and various, some affecting principally the cultivated trees in windbreaks and shelterbelts, and others affecting the forest plantations and large areas of timber. Some injure or destroy the trees or tree seeds, and others do damage to the land on which they grow. Saw-Flies and Tent-Caterpillars. At present perhaps the most serious injuries to cultivated trees in this section result from the neglect to take precautions against leaf-eating insects. such as saw-flies and tent-caterpillars. Figure 22. Elm tree that has been planted five years and was pruned to a bare pole when set out. These injuries may be largely prevented by the use of Paris Green, in a liquid form, ap- plied by means of a force pump, using the solutions from a barrel carried in a wagon or on a stone boat. An ordinary spraying noz- zle should be used, with a sufficient Iength of hose to reach up into the tree. In order to reach the tops of the trees it may be neces- sary to have a raised platform on the wagon, and to attach the noz- zle to the end of a long bamboo pole. In most prairie groves this is practicable, but with very high trees it is very difficult if not entirely impracticable, INJURIES TO TREES. 105 Borers and Lice. These sometimes cause scrious injury, but it is seldom practicable to combat them successfully. It is generally better to avoid them by planting the kinds that are least subject to injury from their attacks. Where lice are injuri- ous, kerosene emulsion or strong tobacco water are good reme- dies. In the case of small trees that can be easily inclosed in a tent, the best remedy is tobacco smoke. Figure 23. White Willow windbreak seriously injured |by successive attacks of saw-fly larvee. A common source of injury to willows. Mice and Rabbits. Seedlings and small trees of some kinds are liable to injury from rodents, such as mice and rab- bits, which gnaw the bark near the surface of the ground, and perhaps girdle the tree. They are most likely to do this when the ground is covered with snow, for this furnishes them with a protection under which they can do their mischief without fear of being molested. In the case of small seedlings such injuries may be largely prevented by plowing a furrow or set- ting boards on edge around the seed bed. If, after each snow- fall, the snow is trodden down so as to make a solid path between the seedlings and the grass or woodland whence the mice come, they will be kept out, as they will not try to work through the solid snow. Seedlings that are badly girdled in winter should be cut off at the surface of the ground, to encour- age sprouts from the roots. To prevent the gnawing of larger trees, paint the trunks with a cement or lime wash made rather 106 ELEMENTARY FORESTRY. thick and containing Paris Green in the proportion of one table- spoonful of Paris Green to a pailful of the wash. If skim milk is used in mixing the wash, instead of water, the material sticks better. Trees that are gnawed badly may often be saved by coat- ing the injured surface with grafting wax. blue clay, or other similar material, soon after the damage is done, so as to prevent the seasoning of the wood, and thus give it a chance to heal over. Where the injury is close to the ground it should be cov- ered with earth. The Pocket Gopher. Trees are sometimes injured by pocket gophers eating the roots. Trapping or poisoning may be resorted to, or bisulphide of carbon may be used to suffocate them in their burrows. , Birds. Most of our birds are helpful in various ways, such as distributing seeds and in destroying injurious insects, and such small injurious animals as mice and gophers. They also add to the beauty of our woods and fields, and to our pleasure and recreation. But some kinds are provokingly injurious by eating the seeds we wish to gather, or by digging up newly-sown seeds. Where they are troublesome on seed beds, they may be kept away by covering the bed with wire netting, which will also serve to keep away other animals. If only birds are trouble- some, mosquito netting may be used, or the seeds may be given a light coating of red lead and dried in land plaster or flour before sowing. The sap-sucker does considerable injury to some trees by making holes in the bark for the purpose of securing insects which go there to feed on the sap. They are sometimes so very injurious that it is necessary to destroy them. The Apple, Box- elder, Maple, and most other trees, are subject to their injuries. Cattle. The pasturing of cows, horses, sheep and other ani- mals in the woodlands is generally a poor practice, as these ani- mals browse off many of the young seedlings, especially those of deciduous trees, such as the Oak, Basswood, Cherry and others, though they seldom eat coniferous trees. They also com- pact the ground, and destroy many small seedlings by their con- tinued tramping, especially when present in large numbers. This is especially true of sheep on the Western forest reserves. Deer, moose, elk and other similar animals are likewise injurious in INJURIES TO TREES. 107 forests, and when abundant may do much damage, though on account of their comparatively small number they do but slight injury. Severe Winters. These may injure many kinds of young seedlings, which when two or three years old will be perfectly hardy. Seedlings of such kinds should be dug at the end of the first season’s growth, and be heeled in over winter, or protected by a mulch or earth covering in winter. Alternate Freezing and Thawing. Secdlings are often thrown out of the ground by alternate freezing and thawing, and Figure 24. Hravinc out sy Frost. (a) Tree in natural position. (b) Drawn up by alternate freezing and thawing. in this way have their roots broken. This is most likely to hap- pen where the ground is bare; if covered with leaves or grass, or shaded in other ways, this seldom happens. The best pre- ventive is to mulch the surface soil with leaves or other simi- lar material, but as mice generally like to live in such places poi- son should be used. It should be placed under the mulch, in tin 108 ELEMENTARY FORESTRY. cans laid on their sides, so they may be readily found in spring and will not be liable to poison the birds. When seedlings are thrown out of the ground by frost they should be pushed back and have the earth pressed against them as soon as the ground is thawed in the spring. Late Spring Frosts are common in the low lands of this section. They injure the trees by killing the new spring growth after it has started several inches. A large number of trees are seriously injured in this way, and are classed as frost tender trees, and those that are not liable to this injury are terméd frost hardy trees. Among conifers the spruces and balsams are much injured by late spring frosts, while our pines and the Tamarack, Red Cedar and Arborvite are seldom if ever injured in this way. Deciduous trees recover from such injuries more quickly than evergreens. Among the deciduous trees most lia- ble to injury from this cause are the Ash, Mulberry, Oak, Maple, Basswood, Black Walnut, Butternut and Boxelder, though they do not ali suffer in the same degree. Among those that are not sensitive to late frosts are the Elm, Willow, Poplar, Birch, Hack- berry, Wild Black Cherry and Mountain Ash. On account of this liability to injury from late frosts, it is customary to study the probability of damage from this cause in given locations, and to plant accordingly. It will often be found that in certain low spots there is greater liability to late frosts, while there is very little injury from this cause on the higher lands. It is customary among European foresters to protect young seedlings of some kinds, particularly Beech, from late frosts until they get up off the ground. For this purpose Birch twenty or more feet high are encouraged at intervals of thirty or forty feet, and the frost tender plants, such as Beech and Spruce, are set out between. The result of this arrangement is that the Birch, which is frost hardy, quite successfully protects the frost tender trees below it. After the frost tender trees are well off the ground, as ten or fifteen feet high, there is comparatively lit- tle danger from this source of injury, and the Birch is removed. Sleet Storms occasionally do much damage by breaking the limbs. Little can be done to relieve the trees, but preventive measures may be taken. If no large crotches are allowed to form in trees, and growth kept as near as possible to one cen- tra] shaft, or the longer branches shortened so as they will not INJURIES TO TREES. 109 exert too great a leverage, the losses may be reduced to a mini- mum. Trees having brittle wood or weak crotches, as the Soft Maple, are much more liable to this injury than those with tough wood, as the willows, oaks and elms, and need more pruning on this account. Evergreens are likely to be broken Figure 25. Trees heavily loaded with ice after a sleet storm. by heavy snows that freeze on the leaves. This may be pre- vented on lawn and shade trees by shaking the snow off from them before it freezes. Frost Cracks are a rather infrequent injury caused by the cracking of trees from center to outside, due to uneven contrac- tion in very cold weather. It is generally accompanied by a loud report. Such cracks are often eight or ten feet long, and occasionally longer. They generally close up again when the wood thaws out, and during the following summer grow over, 110 ELEMENTARY FORESTRY. only to burst open again the next winter. This alternate burst- ing open and growing over may continue for many years, until very conspicuous and peculiar wounds are formed. In such cracks insects and rot-producing fungi find favorable lodging places, and as a result trees are seriously injured, and are liable to decay in the trunk. ‘There are no practical remedies for such injuries. Wind. Jnjurics from wind are common where thinning is done to a great extent at one time about shallow rooted trees, such as Spruce growing on moist soil. These injuries can be avoided only by thinning gradually. In many such cases, on timber lands, thinning is im- practicable, and it is then best to cut all the merchantable timber, for if left it is sure to be blown down. On our prairies, where the soil is light and easily moved by the wind, it is not uncommon to have young seed- ling trees seriously injured by the blow- ing away of the soil around the roots, which often leaves them uncovered for three or more inches. This injury usually takes place in the spring, and may be almost entirely prevented by seeding the land to oats about the mid- dle of July, at the time of the last cultivation. Sown at this season the oats form a good sod that serves to hold the soil in place until spring, when it is easily broken up by cultiva- tion, but even then the roots prevent the blowing away of the soil. Occa- sional strips of grass are also a_pre- ventive of this injury, or mulching may be resorted to. Snow Crust. ‘The settling of a snow crust that has formed on the top MS of deep snow drifts may cause injury to young trees by stripping off their fuente 26, Old Frost peanolies aid breaking the stems. It Cracks in Sugar Maple. Pranc 1 8 INJURIES TO TREES. 111 may be prevented by breaking up the crust or by thinly scat- tering over the snow some sand, ashes or other material that will absorb the sun’s heat and cause the crust to melt before the snow underneath melts. This injury seldom occurs except under drifts, and a little good judgment in selecting the loca- tion and arranging the windbreak so as to prevent drifts may obviate this source of injury. Drouth. [njuries from drouth may be prevented to a great extent by constant cultivation, but where this cannot be done mulching is a good substitute. Attention to thinning at the proper time so as not to get the soil filled with roots will also Figure 28. Section of Trunk of Sun-scalded Basswood. Showing dead bark and amount of wood de- cayed. The top and roots of the tree from which this section was cut were perfectly healthy at the time when the trunk broke off at the sun-scald. Figure 27. Trunk of Soft Maple badly sun- scalded. help to prevent injury from drouth. Willow windbreaks can be grown without any cultivation, after being once well established, in the driest portion of Minnesota, if they are kept mulched with straw or litter for six feet on each side. Mulching also prevents injury from severe freezing of the roots. 112 ELEMENTARY FORESTRY. Sun-scald. Nearly all of our cultivated trees may be injured by sun-scald. This occurs, almost without exception, on the southwest side of unprotected trees of Hard and Soft Maple, Basswood, Boxelder, Black Walnut, etc. Oaks and all other trees are occasionally affected. It never occurs when the trees are sufficiently close together to shade their trunks, and for this reason the growth of shrubs and low branching trees should be encouraged on the south and west sides of groves where they do not crowd the principal kinds. Street trees liable to this injury may be protected by burlap sacking, straw, or other simi- lar material. When injuries from sun-scald occur, the loose bark should be cut off down to the live growth and the wood coated with paint, to prevent its seasoning, or the wound wrapped in cloth. Trees inclined to the northeast are most liable to sun- scald, because the rays of the sun strike the trunk more nearly perpendicular. Broken Branches and Decay. Large wounds are some- times formed by the breaking down of a branch, or by decay, which may have started in a wound made by pruning. In such cases the broken and decayed wood should be cleared away, and the exposed surfaces treated with a very heavy coat of white lead paint, grafting wax, or other material that will keep out water and disease. If the wound is very large, or forms a hole in which water is likely to stand, it should be cleaned and painted as recommended, and then coveied with a sheet of zinc, care- fully tacked on, and the joints closed with grafting wax to keep out water. Fungus Diseases are quite common sources of injury to trees of all kinds, including those of our forests. They attack the foliage, trunk and roots. Occasionally very serious losses occur here from those that cause the trunks to rot. They are generally most numerous in sections where there is not much of a circulation of air. This subject is too large for a detailed account of any of them here, and only one is referred to, which, although not very common, is occasionally quite injurious. This is known as the toadstool root fungus, Agaricus melleus. This fungus lives upon the roots of pines, spruces, firs, etc., and occa- sionally kills them. At one stage of its growth it lives on the decaying wood of oaks and similar trees. INJURIES TO TREES. 113 FOREST FIRES. Forest Fires are the one great cause of injuries to forests in this section. All other causes of injury are very slight in comparison to it, and could this one cause be removed it is more than probable that the natural renewal of our timber lands would be sufficient to maintain the timber industries of Minnesota for very many years to come. Fires in this state have destroyed large areas of pine log tim- ber before it could be made accessible to market. It is undoubt- Nara sai et N Ni WM hh ei Jf Ig ee y ik pL M4 Min Figure 29. Agaricus melleus, a fungus that is occasionally very injurious to trees by destroying their roots. (a) To S> Do Sr DC ¢ rs WHODDNIANRwSNUOCOHAROBRWWH SOY Sa00 AATMAANIT SA PARE SR EE WW WWW WWWWNNWNNNNNWNWHE EEE EERE COOCSCOCCOCSS AM AWWH DO WDIRON RWW HEH ODDIBDMIP WNW HOOD AWRNEWNHOODIDURWNUHSDERRMOE We oo ~ | pos | ya) pe ~ t iy hy MH hu a em it i v Pra uv DY vu Us vu Us v gs | Ee gs Es | gs ee | a Ee gd eee | eed Ce Se te a ee Ohl eS ae al) Bes ES ||as| SF ||ae a6 ||AS| ad BE| 23 0. 11.4] 0.7089] | 17.1 | 1.59 28.5 0. 11.5] 0.7214] | 17.2) 1.6 28.6 0. 11.6] 0.7340] ] 17.3) 1. | 28.7 0. 11.7] 0.7467] ] 17.4] 1. .f 28.8 0.5 11.8] 0.7595] | 17.5] 1 s 25.9 0.2 11.9] 0.7724] 17.6) 1.68 : 29.0 0.3 12.0] 0.7854] | 17.7} 1. 98 29.1 0.2% 12.1] 0.7986] | 17.8] 1.7: : 29.2 0.25 12.2] 0.8118]] 17.911. bie 29.3 5| 0.2 12.3] 0.8252]| 18.01 1.7 7/3. 29.4 0.2 12.4 | 0.83887]] 18.1] 1.7 3.813. 29.5 0.2 12.5 | 0.8523] 18.2] 1. .9| 3. 29.6 0. 12.6 | 0.8660] | 18.3] 1. .0| 3. 29.7 0.2 12.7 | 0.8798] | 18.4 | 1. S13; 29.8 | 0. 12.8 | 0.8987 |] 18.5] 1. .2|3. 29.9 | 0.2 12.9 | 0.9077] ) 18.6] 1. 4.3 | 3.2% 30.0 | 0.5 13.0] 0.9218] | 18.7 | 1.$ .4/8.2 30.1 0. 13.1] 0.9360] 18.8 | 1.9% 5/3 30.2 UE 13.2| 0.9504] | 18.9] 1. 6) § 30.8 0.8 3} 0.9684]] 19.0] 1. val 30.4 0.8 3.4] 0.9794] | 19.1 1.5 8]: 30.5 0.3 3.5 | 0.9941] | 19.2] 2. 9) 5 30.6 0.5 3.6 | 1.0089] | 19.3 | 2.05 -0|§ 30.7 0.5 3.7 | 1.0237] | 19.4] 2. 1] 5 30.8 0.5 3.8] 1.0887] ]19.5| 2. 2 30.9 0.: 3.9] 1.0538]! 19.6 | 2.0 : 31 0.8 .0| 1.0690} | 19.7 | 2. 5.4 32 0.3: -1| 1.0843] | 19.8 | 2.12 5.5 | § 33 0.39 .2| 1.0997] | 19.9 | 2.17 6% 34 0. -8| 1.1153] | 20.0| 2. a 35 0. 4] 1.1309] | 20.1] 2. 8 36 0.42 .5 | 1.1467 | | 20.2 | 2 “9! 37 0.43 6 | 1.1626] | 20.3 | 2.2 0 38 0. .7| 1.1785] | 20.4} 2. Bil 39 0.451 -8| 1.1946] | 20.5 | 2.2 2 40 0.461 .9 | 1.2108] | 20.6 | 2.8 B85 41 0.4718] | 15.0] 1.2272]] 20.7] 2. 4 42 0.4820] | 15.1] 1.2437]] 20.8 5 43 0.4923 || 15.2] 1.2602}| 20.9) 2. 6 44 0.5027} | 15.3] 1.2 10) 2. 6.7 45 0.5132] | 15.4 | 1.28 el [12 18 i 46 0.5238] ]15.5 | 1. toner 9 7 5345 |/15.6| 1.4 BY] 2. £0 48 isiey dal es .4/2 1 49 5.81.5 5/2. 2 50 5.9] 1. .6| 2.8 8 51 5.0] 1.38 7/2 4 52 1] 1. 8] 2.5 5 58 3.2] 1.4314 9] 2. 6 54 3.8} 1.4492 0/2. AG 55 3.41 1.4670 11/28 8 56 3.5] 1.4849] | 22.2] 2. 9 7 4 3.6] 1. 2.312. 0 58 0.6600 }]16.7|1 4] 2 a 59 ¢ 0.6721] | 16.8] 1.5 4] 2. 2 6u | 19.6350 0.68421) 16.9] 1. 66/2. BI 0.6965 7.0!11.5 712.8 4 MEASUREMENT OF GROWING STOCK. 137 MEASUREMENT OF GROWING STOCK. The Growing Stock of a Forest, or Volume of Stand- ing Timber, is equal to the sum of the volumes of all the trees. Where the tract is small caliper all the trees, or if the tract is large caliper all the trees on a small sample area selected as typical of the whole. If each species is in uniform stand, separation into species classes will be sufficient, but where much difference exists between individuals of the same species, due to conditions of growth, diameter and height classes in each species should be formed, and the volume of each class com- puted by itself. From the diameters obtained by calipering at breast height the average basal area is determined in each class, and trees of corresponding diameters in each class are felled and measured accurately. The volume of a sample tree, or the mean volume of several sample trees, times the number of trees, gives the volume of that class, and the sum of the volumes of the dil- ferent classes is the total volume of timber on the tract. The more sample trees that are measured the more accurate will be the results, as trees vary so much in shape that quite different volumes may be obtained for two trees of the same diameter and height. A Sample Acre of Jack Pine Shows the Following Stand: Diameter, Basal Breast Height. No. Trees. Area, BZ TMENE Si, asusainy arse aaa aR al 0218 BVAMICM ES nuh cd Marmara tat nie ce aise ee NO 2946 And chestns| bll2e lho) ell eg lhe! ez lhe) Bll 2o lhe] > oe =/,e ioe SlILS|(SBgI1SS/ (6 )// Bae sl) oc) oe sa) a Sa lPElEE SE |OEIEE || 25 [GEIRE || S5 |SE/RE || & 8 |SE|RE Un |FOlug Un | Polos Ven |eSivoS ll) our |rpolos Ur |F Olu MA 4h [PB |) 4A [qh |bo |] aA lao SE || a8 |e 25 | aA aa am | i} 2.0 | 144] 156 || 5.9 | 49 | 54 || 9.7] 29 | 32 || 18.5 15 “it 39 | 6.9! 7.8 2.1 | 138 | 150 || 6.0 | 48 | 53 |} 9.8) 29] 32 ||19.0 14 (16 40 |6.8 7.6 2.2 | 132] 144 || 6.1 | 47 | 53 |} 9.9] 28 | 32 |1195 14 |16 41 |6.6) 7.4 2.3 | 127 | 139 |] 6.2 | 46 | 52 || 10.0] 28} 81 |] 20.0/14 [15 42 |6.4)| 7.2 2.4 | 122) 134 |] 6.3 | 45 | 51 || 10.2) 27 | 31 |} 20.5 /13 {15 43 16.38/71 2.5 [117] 129]| 6.4 | 45 | 5u |] 10.4] 27 | 30 )} 21.0113 [15 44 |6.1) 6.9 2.6 | 113) 124 )| 6.5 | 44 | 49 |/10.6| 26 | 30 || 21.5113 |14 45 |6.0) 6.7 2.7 | 109 | 120 || 6.6 | 43 | 48 |] 10.8) 26} 29 ;} 22.0 12 14 46 15.9 6.6 2.8 | 105 | 116 |} 6.7 | 42 | 48 |] 11 0) 25 | 28 |} 22.5 j12 |14 47 15.8) 6.5 2.9 | 101 | 112 || 6.8 | 42 | 47 |] 11.2] 25 | 28 || 238.0 ]12 1138 48 |5.6| 6.8 3.0 | 98] 109]| 6.9 | 41 | 46 ]| 11.4) 24 | 27 || 23.5 |12 {13 50 |5.4| 6.1 3.1 | 95} 105 || 7.0 | 40 | 45 |] 11.6) 24 | 27 |] 24.0 11 [13 52 | 5.2) 5.9 3.2] 92] 102]| 7.1 | 40 | 45 |} 11.8] 23 | 26 |) 24.5 |11 {12 54 |5.1| 5.7 3.3] 89) 99 |] 7.2 | 30 | 44 | 112.0] 23 | 26 |} 25.0/11 12 56 | 4.9) 5.5 3.4] 86) 96]] 7.3 | 89 | 44 ]]12 2) 23] 26 |125.5 |11 12 58 | 4.7 | 5.8 3.5 | 84] 93]) 7.4 | 88 | 43 ]] 12.4) 22] 25 |/ 26.0110 |12 60 | 4.5) 5.1 3.6 | 81] 91]| 7.5 | 88 | 42 || 12.6) 22] 25 || 26.5 10. |12 62 ] 4.4) 4.9 3.71 79| 88|| 7.6 | 87 | 42 112.8 0.10/11 64 14.2) 4.7 8.8 | 77| 86|| 7.7 | 87 | 41 |] 18.0 5} 99/11 66 | 4.1) 4.6 3.9] 75] 84|| 7.8] 86 | 41 |} 13.2 0) 9.7 11 68 |3.9| 44 4.0 | 73] 81 ]| 7.9 | 36 | 40 |] 13.4 .5| 9.511 70 | 3.8) 4.3 4.1] 71] 79]) 8.0 | 85 | 40 |) 13.6 .Q| 9.3/11 72 |3.7| 4.2 4.2 | 69! 771| 8.1] 85 | 39 |] 13.8 -5/ 9.2/10.5]| 74 |3.6) 4.1 4.3] 68| 76 || 8.2 | 34 | 39 |] 14.0 0.0| 9.0/10.0]} 76 |3.6) 4.0 4.4] 66] 74!| 8.3] 84 | 38 || 14.2 5} 8.9)10.0|| 78 | 3.5) 3.9 4.5] 65) 72 || 8.4 | 84 | 88 |) 14.4 .0/ 8.7) 9.8|| 80 |3.4| 3.8 4.6 | 63| 70 || 8.5 | 33 | 87 |) 14.6 .5| 8.6| 9.7|| 85 | 3.2) 3.6 4.7] 62) 69|] 8.6 | 83 | 87 |) 14.8 2.01 8.5/9.5]! 90 |3.0) 8.4 4.8) 60} 67 || 8.7 | 32 | 86 |) 15.0 2.51 8.4) 9.4]| 100 | 2.7) 3.0 4.9 | 59] 66]} 88 | 32 | 36 || 15.2 3.0} 8.2| 9.2]| 110 | 2.4) 2.7 5.0| 58| 65 |) 8.9 | B2 | 85 |} 15.4 33.5 8.1] 9.1]| 120 | 2.2] 2.5 5.1| 56] 63|| 9.0] 81 | 35 || 15.6 34.0| 7.9| 8.9|| 120 | 2.1| 2.3 5.2) 55| 62]| 9.1 | 31 | 85 |/15 8 34.5| 7.8} 8.8|| 140 ]1.9] 2.2 5.3| 54] 61]} 9.2 | 31 | 84 |} 16.0 35.0| 7.7) 8.6|| 150 | 1.8] 2.0 5.4} 53| 60 || 9.3 | 30 | 34 || 16.5 85.5 | 7.6| 8.5]| 170 | 1.6] 1.8 5.5 | 52| 59|| 9.4 | 80 | 84 |) 17.0 36.0} 7 5| 8.4]| 200 | 1.3) 1.5 5.6] 51) 57 || 9.5 | 29 | 38 || 17.5 7.0) 73) 8.2]] 250 } 1.1] 1.2 5.7 | 50] 56]| 9.6 | 29 | 83 |} 18.0) 15 | 17 || 88.0] 7.1) ¥.0]} 300 | 0.9) 1.0 5.81 49! 55 | In Determining the Accretion of a Felled Tree the volume is computed from actual measurements. By a few trials the top is cut off where the section contains as many rings as there are years in the period for which the accretion is desired, and the height of the tree at that time measured. The difference in volumes past and present gives periodic accretion. The diameter for both the past and present tree may be taken at the middle of the topless stem, and volumes found by multiplying ELEMENTARY FORESTRY. 142 S vings eet tees one Se ests et The progressive volume of a tree. Figure 28. ACCRETION OF A FELLED TREE. 143 their respective cross-sectional areas at that point by the length of the topless trunk. A more careful stem analysis of a tree affords detailed meas- urements from which the volume at any time during its lifetime may be determined very accurately. The following table of measurements of a pine will furnish data for the calculation of its volume at different ages, and its progressive development is graphically illustrated in Figure 38: ‘S 4 “ Accretion in inches during past +g Sy ~ | eT ae eee 7 Sapa ee a gro | aid | 1 ; . ee | BG | BS |} Age} 19 | 20 | 30} 40 | 50 | 60 | x0 9 = om 2 years. |years. years. years.|years. years. years. me | 628 | Aes | soe cles mabe neta sicceat | Geadst | = he —s 2 9.3 8.52 | 65 -54 | 1.10 | 1.6 2.80 | 8.70 | 4.26 10 7.8 7.16 57 50 94 | 1.3 2.68 | 2.70 18 Tal 6.98 51 57 | lov | 1 3.37 | 3.49 | 2 | 63 | 588 | 2 | ‘42 | ‘99 | 1. 2.04 | | 34 5.7 4.92 39 edd] 1.03 | 1 42 t.4 3.94 28 -48 | 1.28 | 1.8 50 | 3.0 | 248 | 19 | (56 | 1.24 | | 58 5 48 5 24 60 Top | The Accretion of a Forest for a given number of years is found by multiplying the accretion of the sample tree for that period by the number of trees per acre and the number of acres in the tract. If the trees are arranged in diameter classes, the accretion of each class is determined, and the sum of accretions of all the classes taken as the accretion of the forest. The Working Plan of a forest contemplates the economic management of the growing crop, so that there may be cut each year not to exceed the amount of the annual accretion; or, if worked on the rotation plan, so that there may be cut at any one time not more than the accretion for the period of rotation, thus leaving the capital stock unimpaired. The methods of measure- ment described are used in outlining this plan. The Estimation of Standing Timber is usually a matter of personal experience on the part of the estimator. No meas- urements are taken of trees, but the estimate is made by men of long experience in the woods. Sometimes their figures are very close, but more often they fall short of the actual stand of tim- ber. Buying and selling timber lands is based on this method of determining the possible crop, both parties sending out their 144 ELEMENTARY FORESTRY. own estimators. The number of trees on typical areas, as an acre in each forty, may be counted, and the sizes estimated. Often all timber trees on a forty-acre lot are counted, and the number of logs per 1,000 feet board measure estimated. For an inexperienced person a good method would be to caliper all trees on typical areas of the tract, and then compute the stand from the cross-sectional area and the average length of timber stick, which could be estimated very closely after a little practice. The greatest dificulty in this work lies in the selection of typical areas and sample trees. All forestry measurements and estimates are only approximations, and it is often found necessary to modify working plans to meet new information and changed conditions. MEASUREMENT OF LOGS AND LUMBER. Logs are Measured in Feet Board Measure by taking the length and diameter at the small end, and by reference to a table the corresponding number of feet board measure is found. This is not usually accurate, but seems to be sufficiently so to satisfy both buyer and seller in this state. Lumber is measured in square feet of surface of a board one inch in thickness, com- monly called board measure, or B. M., for short. Scaling Logs in Minnesota is a Simple Matter. It is done after they are cut from the tree and marked, wherever con- venient,—in the woods, on skidways, on cars, on the river, or elsewhere. For straight, sound logs no experience is necessary, but for defective logs the scaler’s judgment is depended upon to make proper deduction, so as to get out good lumber. Private scalers may be employed by those interested, but, to avoid possi- ble litigation over sales, it is advisable to have the surveyor gen- eral of logs and lumber for the district appoint an official scaler to do the work. The scalers enter in a book carried for the pur- pose the number of logs scaled, the length, the feet B. M., the mumber of each log if numbered, the section, township and range where cut, and the markings. These books are kept on file in the surveyor general's office for future reference. There are seven lumber districts provided for by law in Minnesota, but in only five has it been found necessary to open ofhces, namely, at Stillwater, Minneapolis, Wabasha, Duluth and Crookston. SCALING. 145 The Minnesota law provides that Scribner’s rule be the only legal rule for the survey of logs in this state, and that every log shall be surveyed by the largest number of even feet which it contains in length over ten feet and under twenty-four feet, and all logs of twenty-four feet or more shall be surveyed as two logs or more. As to what Scribner’s rule is the law does not say, and yet requires it to be posted in the offices of the surveyors general of logs and lumber. The following table is a copy of Scribner’s rule as used here: SCRIBNER’S RULE. Ww bh Y Loc LENGTHS IN FEFT. vs E43 ie l l Se 12. 4. aide 16 | 18 | 20 22 AR | vee | 8 24 32 40 44 48 9 30 40 45 50 55 10 40 50 5D 65 7 11 50 65 70 80 90 12 5Y 79 88 98 108 13 B 7 109 122 134 14 86 114 129 143 15¢ 15 107 142 160 178 196 16 119 159 178 198 218 17 139 185 208 232 255 18 160 213 240 267 298 19 180 240 270) 300 330 20 210 280 B15, 350 385 21 228 304 342 380 418 22 251 334 76 418 460 23 283 77 424 470 B18 24 308 404 454 505 BBS 25 344 459 516 513 681 26 BIB 500 5A? 625 688 27 411 548 616 684 758 28 436 582 654 728 800 29 457 609 635 761 $88 30 493 657 739 821 904 31 532 710 799 888 6 32 52 736 828 920 | 1012 BB 588 784 882 980 Bd 600 800 900 | 1000 35 657 876 985 | 1095 36 692 923 | 1038 | 1152 | 7 772 1029 | 1158 | 1287 38 801 1068 | 1201 39 840 1120 | 1260 | 40 903 1204 | 1354 | 41 954 127 1431 | 42 1007 1343 43 1046 1396 44 1110 1430 | 45 1139 | 1587 46 1190 1656 47 1242 | | 1728 48 1296 | 1818 | 146 ELEMENTARY FORESTRY. The Number of Feet B. M. which May be Obtained from a Log varies with the management of the cutting, the width of kerf, the width of boards, whether one or two inch boards, or some of both are cut from the same log. Usually the cut exceeds the scale. Take, for example, a log sixteen inches in diameter at the small end, eighteen inches at the middle, twenty inches at the large end, and twelve feet long. Such a log con- tains about 21.2 cubic feet. The official scale gives 119 feet B. M., which is equal to 9.9 cubic feet. The actual cut should give 155.75 leet B. M., or thirteen cubic feet of lumber, the slab would be about 5.3 cubic feet, and the kerf (sawdust) about 2.9 cubic feet. From this it would appear that the Minnesota official scale gives the seller 46.7 per cent of his log, while the mill turns out 61.3 per cent in lumber, 13.7 per cent in sawdust and 25 per cent in slab. The producer loses 53.3 per cent of the scaled log; but that is not all his loss. In marking logs to be cut the under- cutter allows at least three inches over the required length to cover loss in checking; that is, a log scaled at twelve foot length would really measure twelve feet and three inches, or more. The Percentage of the Logs,on which the seller or pro- ducer gets returns varies with different sizes and shapes. The following table will serve as a comparison: | Scale Per cent Diameters Lengths __ | Volume of Actual Inches. Feet. | C.F. | Volume | | B.M. | C.F. | Scaled. 16 | 25.5 .8 22 24. 59.4 16 | 17.6 53.9 16 | 13.3 52.8 16 11.8 , 39.5 14 10.6 8 .f 57.9 12 9.9 21. wap 12 12 16. 42.9 12 7.2 13. 52.2 20 5.4 15. B44 16 5.4 12. 42.9 16 | 5.4 ll. 47.0 IPSs | 4.2 ll. 37.8 | 1 | 4.2 10. 39. 16 | a ec, 37 | 16 ‘ 4.9 16 | | 3.8 8.7 16 | | 2.7 79 16 2.7 8.7 1 C163" | ep | 27 9.6 } 12 | 24 | 2.0 | 6.5 | 12 | d | 2.0 3 12 2.5 | 6.5 FOREST INSTRUMENTS. 147 In practice these discrepancies are equalized as the result of the ordinary trade relations, and are not liable to work serious injustice under present conditions, and are here stated only to call attention to our crude methods of measuring timber. INSTRUMENTS USED IN FOREST MENSURATION. The Equipment of a Forester, while not extensive, must be complete for the work in hand. He surveys the land, lays out roads and ditches, cuts down trees and saws them into logs, measures diameters of logs and growing trees, takes heights of trees, determines rates of growth, estimates and measures tim- ber and cordwood, and maps and plats his work. Where there hhas been a survey of land by the government, as in this state, he will not be called upon to make one, as maps sufficiently reliable for his purpose may be had from official records; but to meet all the requirements of his position the forester should be an expert surveyor, and provided with all the necessary instruments for the work, including drawing instruments, tables, stationery, etc., for office work, in mapping and platting his field observa- tions. The work of forestry mensuration is concerned mainly with taking diameters and heights of trees, determining the areas on which they stand and the rate of growth. For Measuring Land Areas the ordinary steel tape, grad- uated on one side in feet, tenths and hundredths, and on the other side in links for convenience in computing acreage, is used —the 100-foot length being preferred. For the same purpose a steel chain is also used, and with the chain or tape should be a set of marking pins and ranging poles. In laying out small rectangular areas, as a sample acre, a cross-staff head, an angle mirror, or an angle prism is used; but for more extended sur- veys and for road and ditch work a transit and level would be advisable, while for the location of lost corners the magnetic compass might have to be resorted to. For the Rough Land Measurement of a Valuation Survey a Steel Chain, Thirty-three Feet Long, is used. This short chain is attached to a stout leather belt about the waist of the tallyman, whose hands are then free to carry the tallyboard holding notebook or tally blanks, and to work with a lead pencil. A small magnetic compass by which the tallyman directs his course is fixed on one corner of the tallyboard. 148 ELEMENTARY FORESTRY. The Diameters of Trees and Logs are taken with a pair of wooden calipers of convenient size for the timber of the district. A limb or scale bar, graduated in inches and tenths, has a fixed arm standing out at right angles at one end, while a second arm is movable along the bar so that the trunk of a tree may be inclosed between them and the diameter read directly from the scale. The fixed arm is held in place by a Figure 39. Calipering a tree. screw so that it may be removed for packing and transportation, or so that a broken part may be replaced. The other arm has an adjustable plate which keeps it at right angles to the scale bar when pressed against the tree. Sometimes the circumference of the tree is measured with a steel tape, one side of which is grad- uated to give diameters of circles whose circumferences are read from the other side. The Heights of Trees are determined by means of a most convenient and useful little instrument, called Faustman’s mir- ror hypsometer. The distance of the observer from the tree is FOREST INSTRUMENTS. 149 measured with a steel tape, and the instrument adjusted to that distance by the slide and vertical scale. The top and bottom of the tree are then sighted and the readings of the marginal scale where the plumb line crosses it added to or subtracted from each other, according as the eye of the observer is above or below the level of the tree. This instrument may also be used Figure 4o. Faustman’s mirror hypsometer. (4BCD.) Frame of in- strument, (E) mirror in which scale is reflected, (a) eyepiece, ()) cross-wire on which object is sighted, (gc) slide and vertical scale for distance of ob- server from tree, (f) spring to hold slide in place, (i) marginal scale which gives height of tree. in taking levels and grades, and may be mounted on a jacob staff or tripod, but is more often used in the hand. Another instrument, called ‘‘Baummesser” by the Germans, mounted on a tripod, is used to take heights, and by means of a stadia attachment the diameter at any point on the trunk of the tree may also be measured. After some practice with one of them a 150 ELEMENTARY FORESTRY. person may become sufficiently expert at estimating the heights of trees to get along without an instrument. The Rate of Growth of a Standing Tree is determined by removing from the trunk a small cylinder of wood with a hol- low auger, called an accretion borer. On this section of wood the annual rings are counted, and their width measured with a pocket rule graduated in inches and tenths, or in millimeters. Figure 41. The mirror hypsometer in use. Where the growth has been slow, and the rings are close, a pocket lens may be necessary to enable one to count them. When a fuller determination of the rate of growth is desirable, trees are felled with an ax, or with a saw, and cut into logs. A small saw is easier to carry around, but a longer, heavier saw does much faster work. The common logging saw of the Min- nesota woods is six feet in length. In making an examination of the end of a log the rough graining of the saw must often be smoothed away before the rings can be counted readily, and this FOREST INSTRUMENTS. 151 Bic maemcmmpeeng, "ER ort enemas <7 Figure 42. The accretion borer, showing handle, hollow auger, with- drawing pin and a core of wood extracted. The handle is hollow, with screw caps, so that the other parts may be carried inside when not in use. Figure 43. Using the accretion borer on the trunk of a tree. 152 ELEMENTARY FORESTRY. is well accomplished with a sharp knife, cutting a broad V notch from the center to the circumference. Miscellaneous Instruments used by the forester. For marking logs, blazing trees, cutting away limbs, etc., a hand ax is a desirable addition to the equipment. It should be small, so as to be conveniently carried in the pocket or in the belt, and should have a leather guard to protect the edge when not in use. As saws and axes will not keep sharp long, if used, a grindstone, whetstones, files and saw sets should be provided. In calipering trees on a small area across which it is necessary to make sev- eral trips, the surveyor avoids repetitions by marking the bark of each tree, as he calipers it, with a metal scratcher carried in one hand. Sometimes a pair of climbers are used to get into the top of a tree for the purpose of measuring upper limbs and diam- eters. The number of feet board measure in logs is ascertained by means of the ordinary log rule, Minnesota standard, used by sealers, and a board rule measures the lumber as it comes from the sawmill. A Camping Outfit is necessary where the work of the for- ester is done in the depths of the forest, far from habitations and railroads, and perhaps a wagon and a team of horses or pack horses should be provided for moving camp and hauling sup- plies. If the area to be worked over is great, the chief of the party should have a good saddle horse, so that he may get over the country quickly, and lay out work for his subordinates who operate on foot. o J CHAPTER XI. FOREST PROBLEMS IN MINNESOTA. The object of this chapter is to give general suggestions which may be applied to a variety of conditions, and not to pre- scribe exact treatment for any special forest problem. It has seemed that certain methods of treatment could be best given in this way. i. A. has a swamp covered with thrifty Black Spruce, in all about seventy-five acres. Last year he got 500 Christmas trees from it, which he sold at eight cents each. There is also some Tamarack and Pine on the higher land. For what trees can this land be used for greatest profit? How long does it take to grow Christmas trees? / Answer: If the Black Spruce are thrifty, it is a very sure indication that the soil is not overly wet during the summer, and that it is in very good shape for Tamarack or other more valua- ble tree. The Black Spruce is a very slow grower, and it is doubtful if it should be encouraged under any condition. Our native White Spruce grows much faster, and this would be much the most profitable of any of our native trees for paper pulp; but some studies by the Minnesota Experiment Station seem to show that the Norway Spruce could be grown at even greate- profit for paper pulp. This tree is fully as rapid a grower as the White Spruce, nearly as hardy, and the seed of it is much more easily obtained. If it is thought desirable to use this land for pulp wood, a small bed of spruce seedlings should be made up near by, in which should be sown White or Norway Spruce seed, and when the seedlings are three or four years old they should be transplanted to the swamp. It would take at least fifteen years to grow Black Spruce to a height of six feet for Christmas trees, while the Norway Spruce could probably be grown to the same height under same conditions in ten years. About 1,800 Christ- mas trees can be grown on one acre of land to a height of six feet and with a spread of five feet. Spruce may be grown closer together than most other trees for this purpose, because the shaded branches are not easily killed out. 154 ELEMENTARY FORESTRY. 2. B. has a Tamarack swamp of 800 acres, from which he has cut all the timber big enough for ties. There is practically no demand for the smaller post timber at present, and he asks what he should do with it, and if it will pay him to hold it. The land seems to be well stocked with young trees of various ages, some of which have been somewhat broken down in getting out the larger tie timber. Answer: Probably the best treatment would be to let it alone. If the land is quite wet there is very little chance of fire doing much damage to it. If, however, it is liable to be dried out it would be a good plan to take some precautions to protect it from fire, if it can be done without too much expense. The Tamarack grows very rapidly, and there is perhaps no tree that will pay better than this, providing the taxes are not too high. While there may be no demand at present for the smaller stuff for fence posts, yet within a few years such a demand is inevitable, as the more accessible Tamarack is now being rapidly sought after for such purposes, and is being shipped in large quantities to the prairie farms. Such a Tam- arack swamp, if carefully looked after, is capable of continuing itself indefinitely and producing a fairly good annual revenue. The advisability of perpetuating such a swamp in Tamarack would depend largely on the demand for hay land, for which pur- poses such land is generally well adapted. 3. 2. Vruiting branch, one- half natural size. 3. Staminate flower, enlarged, 4 Distillate inflores- cence, enlarged, OAK. 295 Tennessee, Indian Territory and Texas. In Minnesota common or abundant in all except the extreme northeastern part. Propagation.n—Very easily grown from seeds planted in au- tumn. The seedlings in good prairie soil attain a height of about four feet in five years. Propertics of wood—Heavy, hard, rather brittle, coarse grained and very durable in contact with the soil; color, rich brown with much lighter brown sapwood. Specific gravity 0.7453; weight of a cubic foot 46.45 pounds. Uses—The Bur Oak is the most magnificent, most durable and longest lived tree for planting throughout this whole sec- tion. It is also one of the most valuable timber trees of North America. Although its wood is rather coarser grained and in- ferior in strength to that of the White Oak, with which it is commercially confounded, yet it is used for the same purposes. Quercus rubra. Red Oak. Leaves oblong-obovate to oblong, moderately sometimes deeply pinnatifid with rounded sinuses, seven to nine narrow lobes, these and the teeth being bristle pointed; mature leaves rather thin, turning dark red after frost in autumn. Cup saucer- shaped or flat, with a narrow raised border of fine scales, sessile or on a very short stalk, very much shorter than the acorn, which is oblong-ovoid or turgid-ovoid, one inch or less in length, with a bitter kernel. Two years are required to ripen the nut, which is consequently found on the old wood below the leaves of the season. Bark smoother than that. of most oaks. A tree seventy to eighty or more feet high, with a trunk three or four feet in diameter. Distribution —From Nova Scotia to the divide west of Lake Superior and to central Kansas, south to Georgia and Ten- nessee. In Minnesota found along the Mississippi river and occasionally in other parts, but is not very common anywhere in the state. Propagation.—Easily grown from fall sown seeds. Properties of wood.—Heavy, hard, strong, coarse grained and liable to check badly in drying. Specific gravity 0.6621; weight of a cubic foot, 41.25 pounds. Uses.—The Red Oak has been used to a limited extent in this country and Europe as an ornamental tree, for which its stately 206 TREES OF MINNESOTA. Plate 35. Quercus rubra, Red Oak. 1. Flowering branch showing immature fruit of one year’s growth, one- half natural size. 2. Stamimate flower, enlarged. 3. Pistillate flower, en- larged. 4. Fruiting branch, one-halt natural size. 5. Longitudinal section of fruit, one-half natural size. 6. Cup, one-half natural size. 7. Mature leaf, ene-half natural size. OAK. 207 form, vigorous growth and fine autumn coloring make it es- pecially desirable. No oak of the Northern States is more easily transplanted. The wood, which in trade is not distin- guished from that of the Scarlet Oak, is used for interior finish- ing, furniture and in construction, and has a beautiful grain for finishing. It is often used for fuel, but is generally though not universally considered much inferior to the White Oak for this purpose. Quercus coccinea. Scarlet Oak. Black Oak. Leaves oblong or obovate, deeply pinnatifid with broad rounded sinuses and slender lobes divergent and divided at the apex into several teeth which are bristle-pointed. When the leaves unfold they are bright red and covered with pubescence, but towards maturity they become shining green and generally glabrous above, the lower side in this section often furnished with tufts of hair in the axils of the veins. The leaves turn a brilliant red or scarlet in autumn, remain on the trees in this section all winter and fall in the spring. The buds are often slightly pubescent, and are smaller and very different from the large tomentose buds of Quercus velutina. The fruit, which ripens in the autumn of the second year, is sessile, or on a stalk which is sometimes an inch long. It is oval or globular ovoid, with a bitter kernel. A common and often large tree in this section, where it is generally termed Black Oak, and is found on gravelly ridges and sandy land interspersed with Bur and Red Oak. Distribution—From Maine to the District of Columbia and west to Minnesota and Nebraska. Propagation.—By fall-sown seeds. Properties of wood.—Heavy, hard, strong, coarse grained, light or reddish brown with thick darker colored sapwood. Specific gravity 0.7¢95; weight of a cubic foot 42.20 pounds. Uscs.—The Scarlet Oak is not planted to so great an extent as the Red Oak for ornamental purposes, but is fully as desir- able because of its beautiful scarlet autumn coloring and rapid growth. The wood is largely used in the manufacture of furni- ture, for interior finishing and for fuel, and is not distinguished commercially from that of Red Oak. 298 TREES OF MINNESOTA. Plate 36. Quercus coccinea. Scarlet Oak. lowering branch, one-half natural size. 2. Pistillate flower cluster, enlarged. 3. Staminate flower, enlarged. 4. VTistillate flower, enlarged. 5. Fruiting branch, one-half natural size, 6, Acorn, one-half natural size. ELM. 299 ULMACEAE. ELM FAMILY. Genus UL MUS. Leaves simple, alternate, two-ranked, short petioled, straight veined, usually rather rough. Flowers appear before the leaves in our species; perfect or rarely polygamous, apetalous, grecn- ish, in lateral clusters; calyx four to nine lobed; stamens four to nine with long slender filaments; ovary superior, one-celled or rarely two-celled, flattened; styles two, short and diverging. Fruit a samara with a broad membranous margin, one-celled, one-seeded, ripens in early summer; seed all embryo. A genus of about fifteen widely distributed species, which are mostly large deciduous trees, three of which occur in our range. Most of the elms produce hard, tough wood, that is often difficult to split. The European species have given rise to many varieties differing from the parent species in many ways, but chiefly in habit of growth and color of foliage. A form of the European Scotch Elm (U. Montana) with pendulous habit, known in nur- series as Camperdown Weeping Elm, has done very well in a somewhat protected location at the Minnesota Experiment Sta- tion, and bids fair to make a very ornamental specimen. The stock on which it is worked (probably U. campestris), however, has sunscalded. In China a white mucilaginous meal is made from the inner bark of the Elm, and is used as food by the mountaineers of the northern provinces and in the composition of incense sticks. The fruit is employed in medicine, and the bark and young fruits are eaten in periods of severe famine. Propagation—The species are grown from seeds and the varieties by layers, budding, and grafting. With the exception of the Slippery Elm (q. v.) the seeds should be sown as soon as gathered. Ulmus americana. White Elm. American Elm. Water Elm. Leaves three to four inches long, obovate-oblong to oval, usually smooth on the upper and soft and velvety on the lower surface, coarsely and doubly serrate, taper-pointed, turning to a bright yellow before falling. Branches small, slender, ascend- ing, at length spreading and pendulous; twigs and buds smooth, 300 TREES OF MINNESOTA. Plate 37. Ulmus americana. White Eim. 1. Fortion of summer branch, one-half natural size. 2. Flowering branch, one-halt natural size. 3. Fruiting branch, one-half natural size. 4. Portion of winter branch, one-half natural size. 5. Flower, enlarged. 6. longitudinal section of flower, enlarged. 7. Longitudinal section of pistillate flower, enlarged. 8. Longitudinal section of fruit, natural size. 9. Limbryo, enlarged. 10. Longitudinal section of seed, natural size. ELM. 301 not corky. Flowers appear in April, in dense clusters, with slender drooping pedicels. Fruit ripe in May, smooth except the edges, which are hairy, with incurved sharp points at the apex.