/c ^* t '//^ <^t NOW TO KNOW THE GRASSES t; R. W. George M. Gray Museum POlXl^ Ho;e, Massachusetts 025. 495 P68 1st ed o= 01 SI tr O m □ o D m ->^ N \ -<. X >-r ry How To Know THE GRASSES -GfiOfge M. Gray Museum Marine Biological Laboratory Pictured-Keys for determining^t??f cS^^^^^n'^Tr^ °^ portant American grasses with suggestions and aids for their study. By RICHARD W. POHL Associate Professor Botany Iowa State College MM WM. C. BROWN COMPANY JLubliskers DUBUQUE. IOWA Copyright 1954 by H. E. Jaques THE PICTURED-KEY NATURE SERIES "How to Know the Insects," Jaques, 1947 "Living Things — How to Know Them," Jaques, 1946 "How to Know the Trees," Jaques, 1946 "Plant FamiUes — How to Know Them," Jaques, 1948 "Plants We Eat and Wear," Jaques, 1943 'How to Know the Spring Flowers," Cuthbert, 1943, 1949 "How to Know the Mosses," Conard, 1944 "How to Know the Land Birds," Jaques, 1947 "How to Know the Fall Flowers." Cuthbert, 1948 "How to Know the Immature Insects," Chu, 1949 "How to Know the Protozoa," Jahn, 1949 "How to Know the Mammals," Booth, 1949 "How to Know the Beetles," Jaques, 1951 "How to Know the Spiders," Kaston, 1952 "How to Know the Grasses," Pohl, 1954 In Both Spiral and Cloth Binding Other Subjects in Preparation Printed in U.S.A. INTRODUCTION N the main text of this book, 293 kinds of grasses are illustrated and keyed out. These are the common- est and most important species of American grasses — those that the beginner is most apt to meet, and those of importance in farming, gardening, weed control, range and pasture management. In addi- tion to those keyed and illustrated, 91 others are mentioned in connection with closely related species, and their distinguishing features are pointed out. The illustrations are all new and have been made from actual specimens. Most of the spikelet drawings were made by camera lucida or projection methods and hence represent individual spikelets, not averages. Drawings of small structures, such as spikelets or their parts, bear measuring scales. These are used to indicate the size of the structures, exactly like the scales used in maps. The scales are marked off into spaces representing millimeters, and the total length of the scale in millimeters is marked. In a few drawings the scale is designed for one particular object, in which case an arrow points to the intended object. The maps included in the species drawings represent approximate ranges of the species. Due to lack of exact information, particularly about the arctic and tropical extensions of these ranges, the maps cannot be entirely accurate, but will serve to give a general idea of the geographic area in which a species may occur in favorable habi- tats. The maps are based upon published records, herbarium speci- mens, and the author's personal information. Drawings marked with the letter B are the work of Mrs. J. Bardach of Iowa State Teachers College, whose assistance is gratefully acknowl- edged. All others are the work of the author. For most species, the period of flowering and fruiting is indicated. These dates cover the entire period during which fully developed and intact inflorescences can be found on the plants. Since grass flowers are rarely used in identification, actual flowering dates are not given. Many persons have aided in the production of this little book. First of all, the author wishes to thank his wife and family, for the gift of time, which allowed its completion. The facilities of Iowa State College, in particular the excellent grass herbarium, were invaluable. Dr. H. E. Jaques, the editor of the Pictured-Key Nature Series, has been constantly helpful. The keys have been tested repeatedly by the au- thor's students, and for their cooperation he extends his heartfelt thanks. Ames, Iowa October, 1953 (^..JLc^JL). Tfc^ The Grass Family ranks near the top of the plant kingdom in the number of species it contains. No other group of plants figures so prominently in furnishing us with food. To know a good number of grasses is a cultural obligation as well as a source of personal satisfaction. Dr. Pohl's keys and illustrations are the result of years of study and work with these interesting plants. His book is well worthy of a place in the Pictured-Key Nature Series and in the library of every plant lover. Editor CONTENTS Page Introduction iii What Is a Grass I Key to Grasses, Sedges and Rushes 2 What Do Grasses Look Like 3 How to Collect and Study Grasses 7 How to Recognize the Tribes of Grasses 10 Some Useful Books on Grasses 13 Pictured-Keys to Common American Grasses 15 Tribe I Bambuseae 15 Tribe II Festuceae 23 Tribe III Hordeae 85 Tribe IV Aveneae 95 Tribe V Agrostideae 102 Tribe VI Zoysieae 129 Tribe VII Chlorideae 131 Tribe VIII Phalarideae 144 Tribe IX Oryzeae 146 Tribe X Zizanieae 147 Tribe XI Paniceae 149 Tribe XII Andropogoneae 176 Tribe XIII Tripsaceae 184 Index and Pictured-Glossary 186 UGHTONA'GLUnEY"SUBJECT WHAT IS A GRASS? F all the world's flowering plants, the grasses are undoubtedly the most important to man. They con- tribute tremendously to the earth's green mantle of vegetation; they are the source of the principal foods of man and his domestic animals. Without the grasses, agriculture would be virtually im- possible: grain, sugar, syrup, spice, paper, per- fume, pasture, oil and timber, and a thousand other items of daily use are products of various grasses. They hold the hills, plains and mountains against the destructive erosive forces of wind and water. In the end, they form the sod that covers the sleep- ing dead. Despite the fact that the grasses are so important to \is, we usually know little about them. Why? Because we think that "All grasses are ahke," or "They are too hard to tell apart." But neither statement is true. There are over five thousand "kinds" or species of grasses in the world and fourteen hundred of these are found in the United States alone. This book contains de- scriptions and pictures of over three himdred of the more common grasses of our coun- try. While many are super- ficially similar, they all have good individual marks of recog- nition. Nobody would at a second glance, for example, confuse foxtail and corn, or quackgrass and oats, or Sudan grass and barley, yet these are all grasses, members of one natural family, the GRAMINE- AE, or grass family. HOW TO RECOGNIZE THE GRASS FAMILY The grasses and their alUes are all members of the great group of flowering plants which we call the MONOCOTYLEDONS. The mem- bers of this group are alike in having one seed leaf, parallel-veined leaves (with few exceptions), and stems in which the vascular bimdles are scattered in the pith. Among the Monocotyledons, members of three famiUes of plants have a "grasslike" appearance and may be confused. These are the grasses (Gramineae), the sedges (Cyperac- eae). and the rushes (Juncaceae). A Httle study of the following key and pictures will show how to separate them quickly and surely. Grasses are easy to recognize. Here are some common ones. 1. Floret of porcupine grass (Stipa). 2. Spikelet and panicle of timothy (Phleum). 3. Branchlet with spikelets of John- son grass (Sorghum). 4. Floret and spikelet of Kentucky bluegrass (Poo). 5. Spikelet of wheat (Triti- eum). 6. Spikelet of proso millet (Panicum). 7. Spikelets of oats (Aveng). 1 HOW TO KNOW THE GRASSES KEY TO GRASSES, SEDGES AND RUSHES la. Flowers with stiif, greenish or brownish, six-parted perianth (calyx and corolla); stamens 6 or 3; fruit a many-seeded capsule; leaves usually wiry and round in cross section RUSH FAMILY (JUNCACEAE) lb. Flowers without evident calyx or corolla, gathered into short scaly clusters (spikelets); stamens 3; fruit with a single seed 2 2a. Leaves in 2 vertical rows or ranks; leaf sheaths usually split, with overlapping edges; stems usually round in cross section and hol- low between the joints; each flower of the spikelet contained be- tween 2 bracts, the lemma and the palea GRASS FAMILY (GRAMINEAE) 2b. Leaves in 3 vertical rows or ranks; leaf sheaths tubular, not split; stems often triangular in cross section and solid between joints; each flower of the spikelet in the axil of a single bract, the glume SEDGE FAMILY (CYPERACEAE) DIFFERENCES AMONG GRASSES, SEDGES, AND RUSHES .GRASS SEDGE RUSH STEM AND LEAF ITU ^^jj^!^ ^3r W T LEAF SHEATH FLORET OR FLOWER Figure 1 2 HOW TO KNOW THE GRASSES WHAT DO GRASSES LOOK LIKE? ROOTS The root systems of grasses (Fig. 2) are always fibrous and the majority gf the roots arise from the lower nodes of the stems. Be- cause of the fibrous nature of the roots, they are excellent soil binders. When we pull up a grass plant, we remove only a small portion of the total root system, which in many species may reach a depth of six feet or more. "^m Roots '_ ^RhiZonr Figure 2 STEMS The flowering stems or culms of grasses (Fig. 2) are jointed and usually round and hollow between the soUd joints (nodes). They may branch, in which case a thin membrane, H- shaped in cross section, lies between the main cuhn and the branch. It is called a prophyllum (Fig. 3), and it grasps the main culm with two flanges and the branch with the other two. Thus it serves as a brace to the weak V-joint between the main stem and the branch. Stems may be erect, or with bent, knee-Uke bases (de- cumbent), or they may trail on the surface of the ground (stolons) and root at the nodes, or they may even grow in the top few inches of soil (rhizomes). The stems of grasses range in size from those like six-weeks fescue, a mil- limeter or two in diameter and a few centimeters tall, up to the giant bamboos, which may attain a height of a hundred feet and a diameter of a foot or more. Figure 3 HOW TO KNOW THE GRASSES LEAVES Apex Midrib Figure 4 The leaves of grasses are always parallel-veined and generally have long, narrow blades. The foliage leaf of grasses (Fig. 4), consists of a sheath, a Hgule, and a blade. There is no petiole. The sheath is the split tubular portion surrounding the culm; the ligule is a little membrane-like or hairy collar which sticks up at the juncture of sheath and blade; the blade is the spreading portion of the leaf. It usually has a conspicuous midrib as well as numerous smaller nerves or veins parallel to the mid- rib. The tip, or apex, of the leaf is sharp pointed. Little projections at the base of the leaf blade are called auricles. In a few genera, notably JBromus, Melica, Schizachne, and Gly- ceria, the leaf sheath has joined edges, forming a tube, much the same as in the Cyperaceae. FLOWER CLUSTERS The flower cluster or inflorescence (Fig. 5) of grasses is always made up of a number of subdivisions called spikelets. The spikelets eduncle ONE-SIDED 5PIKE PANICLE i-ROWED 5PIKE: RACEME Figure 5 HOW TO KNOW THE GRASSES are arranged in panicles, or two-rowed spikes, or one-sided spikes, or racemes. The parts of the inflorescence include the stalk or peduncle, the central axis or rachis, main and small branches, and the stalks of the individual spikelets or pedicels. At the base of each branch there may be found a Uttle swelling, the pulvinus, which helps spread the branch of the inflorescence when it emerges from the sheath. SPIKELETS Since the flowers of grasses are minute, simple, and very similar, they are rarely used in classification. Instead, we look for differences in the bracts (modified leaves) which surround the flowers. The unit subdivisions of the inflorescence are called spikelets (Fig. 6). The LEHHA 2:GLUnE RACHILLA [FLORET 5^'^^^- PALEA fGLUME RACHILl CALLU PEDICEL A\JN- TOOTH- LEMMA 5TAnEN5 Figure 6 simplest sort of spikelet is merely a tiny scaly branchlet of flowers, each flower being surrounded by two bracts. At the base of this branchlet there are two bracts which have no flowers in their axils. These are the first and second glumes. The remainder of the spikelet is made up of flowering units called florets, which are arranged alter- nately in two rows on a central stalk, called a rachilla, which is usually concealed by the overlapping florets. Each floret consists of an outer bract or lemma and an inner bract or palea, with the naked flower between them. The lemma corresponds to an ordinary foHage leaf, the palea to the prophyllum, and the flower to a branch. During the brief time of flowering, two little bUsters, the lodicules, which he be- tween the ovary of the flower and the lemma, swell up and force the lemma outwards. This allows the stigmas and stamens to protrude. The lodicules are the evolutionary vestiges of a calyx. If you can find smooth brome grass, orchard grass, or any one of many other grasses in bloom in the morning dew, you can usually observe the lodicules with a hand lens. The actual flower consists of two lodicules, three stamens with long slender filaments, and cm ovary with two feathery HOW TO KNOW THE GRASSES stigmas. All grasses are wind pollinated except the few which are self pollinated within closed florets (cleistogamous). The lemma has a midrib and a number of smaller "veins" or "nerves" running roughly- parallel to it, but converging toward the tip. The midrib of the lemma may be prolonged into a beard or bristle, called an awn. Rarely the lateral nerves also protrude. If the lemma is prominently folded along the midrib, it is said to have a keel. The hardened lower end of the lemma is called a callus. The palea always has two veins near the sides, but lacks a midrib. In some grasses the palea is small or lack- ing. Usually the spikelet has a stalk or pedicel, or this may be absent, as in wheat and rye, and then the spikelet is said to be sessile. Usually spikelets break up at maturity into individual florets, each of which will then bear a segment of the rachilla. Some spikelets, like those of switch grass and foxtail grass, do not break up, but are shed from the plant whole. Often it is necessary to determine at what points the spikelets break or disarticulate. When the spikelets are mature and dry, they will disarticu- late naturally, but if one has a rather immature plant, it may be necessary to tease the spikelets apart with needles and tweezers or with the finger nail in order to tell where the disarticulation will occur. There are two general types of disarticulation: below the glumes (Fig. 7, a), and above the glumes (Fig. 7, b). Spike- lets which disarticulate below the glumes leave nothing on the plant except the stubs of the pedicels. Those which disarticulate above the glumes leave them on the plant. Spikelets of this type usually dis- articulate between the florets as well. Another feature of the spikelet which we may need to know is its shape in cross section. Spikelets may be round in cross section (Fig. 8, a), or flattened from the sides of the glumes and lemmas (laterally Figure 7 b V Figure 8 6 HOW TO KNOW THE GRASSES compressed), as in Fig. 8, b; or flattened from the backs of the glumes and lemmas (dorsally compressed), as in Fig. 8, c. The kind of spikelet pictured in Fig. 6 is probably the basic type, from which reduced or more compUcated sorts have been derived by various changes. In studying other types of grass spikelets, we should mentally compare them with the basic type in order to decide which parts have been modified or eliminated. The following types of changes are common, and they characterize large groups of grasses: 1. The glumes may become large, covering the whole spikelets (oats and its relatives). 2. The upper florets may become eliminated, so that the spikelet is one-flowered (red top, timothy, and their relatives). 3. The lower florets may become sterile and much reduced in size, the upper one remaining fertile (canary grass, foxtail). 4. The glumes may become reduced to little ridges on the tip of the pedicel (rice, cut grass). 5. Either stamens or pistil may be eliminated, giving rise to spike- lets or plants of one sex (salt grass, creeping love grass, Texas bluegrass, corn, Sorghum, wild rice). HOW TO COLLECT AND STUDY GRASSES ROBABLY there is not a county in the United States where less than fifty to one hundred different species of grasses are to be found. Some will be very com- mon and conspicuous, but others will be rare and hard to find. Al first, all may look rather similar, so that sharp observation will be needed to detect even all of the common grasses around us. Don't be afraid to get down on hands and knees and crawl to get a good look. Each sort of habitat will have its own grasses: look in prairie, woodland, marsh, bog, ditches, corn or cotton fields, deserts, mountain meadows, or alpine summits, and you will probably be re- warded with a different set of species each time. Even in the same locality, new species come into flower throughout the spring, summer, and fall. Grasses are easy to collect and prepare, so one should always take care to make good specimens, which will be a pleasure to study later. HOW TO KNOW THE GRASSES The tools needed for collecting grasses are simple. First of all, you will need some sort of digger, so that you can get the important under- ground parts of the plants. I use a long, stout screwdriver, but large hunting knives, geologists picks, or entrenching tools are also satis- factory. Whatever tools you use, be sure to get the parts of the plant that lie below the ground level. Frequently an otherwise good speci- men becon;es very difficult to identify because the collector has ne- glected these structures. After digging a specimen from the ground, one should knock the dirt from the roots or wash them clean. If the plant is too bulky to press flat it may be subdivided and some of the extra inflorescences saved to provide spikelets for dissection. Each specimen is placed in a single folded newspaper sheet (12 x 16 inches as folded) for dry- ing. Information which you would like to keep, such as the location, type of habitat, and the date, should be written on the mar- gin of the paper. If the specimen is too long to fit in a folder, it may be doubled back one or more times. Crumpled or tangled parts should be smoothed out. The bent stems can be held in place by Httle sHps of card with a slit cut in each (Fig. 9). The Figure 9 grass specimens in their paper folders may be carried between sheets of beaverboard or plywood, with a light strap around \he bundle, for periods as long as a day, before it is necessary to dry them. e Final drying of the specimens is accomplished by placing them, in their folders, between 12 x 18 inch blotters made of builders' deaden- ing felt (obtainable from lumber yards, in rolls), or between thick pads of newspapers. The specimens must be kept under pressure until dry, either by placing boards on the sides of the bimdle and strapping it tightly, or by placing heavy weights on top of the bundle. Each day the damp blotters or newspaper pads must be removed and replaced with dry ones. The damp blotters may be dried by laying them out in the sun on dry paving (not grass) for a short while. In wet weather, the blotters can be cautiously dried in a warm oven. Usually grass specimens dry in a few days. After drying, they may be handled in the paper folders, but they will keep better if they are mounted on paper. One may mount specimens in large scrapbooks, or better still, on standard herbarium sheets which may be purchased from biological supply houses. Specimens may be glued to paper by placing them momentarily on a large sheet of glass covered with thin glue, brushed to a thin uniform layer. Fish glue, carriage glue, or LaPages Special 8 HOW TO KNOW THE GRASSES A Tin Paste are satisfactory for this purpose. PU.Tj tf low*. /4m< t p.w.P.fcl J»».V>,I1'*1 Figure 10 which are glued to the sheet. Each specimen, after gluing, is then dropped onto a sheet of paper. Since grasses are often quite waxy, they do not always stick well and should also be sewed to the sheet with string or fastened down with narrow strips of gum- med cloth tape (see Fig. 10). Do not use "Scotch" tape, since it becomes sticky and brittle with age or pulls loose. A label, bear- ing the name of the plant, the place and date of collection, and any other pertinent in- formation, should be glued in the lower right corner of the sheet. Loose spikelets or other small parts may be placed in small coin envelopes When considerable numbers of specimens are needed, for use in classes or for display, they may be preserved by tying them in sheaves and allowing them to hang head down until dry. The equipment which one needs for studying grasses is simple and inexpensive. A good hand lens, of ten to fifteen power is essen- tial, and should always be carried when collecting. A pair of dis- secting needles, well sharpened, are needed. A small scalpel, made by heating and pounding out the tip of a large needle, then retemper- ing and sharpening the edge, is a great help. These can sometimes be purchased through biological supply houses. A pair of good tweezers, preferably with curved tips, a razor blade, and a millimeter scale complete the equipment. When available, a low power binocular microscope will speed and simpHfy the job of seeing. If such a micro- scope is not obtainable, one might mount a hand lens on an impro- vised stand, so as to leave both hands free for dissecting the speci- mens. To soften dried grass spikelets so that they may be dissected more readily, one may apply a few drops of a strong solution of Dreft or Vel in water. HOW TO KNOW THE GRASSES HOW TO RECOGNIZE THE TRIBES OF GRASSES HE common grasses of the United States are grouped into thirteen tribes, or subdivisions of the family. With a Httle practice, it is usually possible to determine the tribe to which a given grass belongs very quickly, thereby making it unnecessary to go through a portion of the key. The following summaries of the characteris- tics of the different tribes should help you to recognize them. Subfamily FESTUCOIDEAE. Spikelets with one to numerous florets; sterile florets, if present, usually at the tip of the spikelet; spikelets laterally compressed or round in cross section; disarticulation usually above the glumes. Tribe I. BAMBUSEAE. Tall plants, with woody perennial cuhns. Spike- lets rarely present. Page 15. Tribe II. FESTUCEAE. Spikelets with several ^ \ ^^ to many florets; glumes not reaching the tip ^^ ,\J^ of the lowermost floret; disarticulation usually above the glumes; inflorescence a panicle. Fig. 11. Pages 23-84. Figure 1 1 Tribe III. HORDEAE. Inflorescence a single terminal spike, with spikelets in rows on op- posite sides of the rachis. Spikelets with one to several florets, usually disarticulating above the glumes. Fig. 12. Pages 85-94. Figure 12 Tribe IV. AVENEAE. Spikelets similar to those of the Festuceae, but with much enlarged glumes, usually covering the entire spikelet. Disarticulation above or below the glumes; inflorescence a panicle. Fig. 13. Pages 95-101. Figure 13 10 HOW TO KNOW THE GRASSES Tribe V. AGROSTIDEAE. Spikelets consisting of two glumes and a single fertile floret. There are never any sterile or rudimentary florets. Spikelets disarticulating above or below the glumes. In- florescence an open or spikelike panicle. Fig. 14. Pages 102-129. Figure 14 Tribe VI. ZOYSIEAE. Spikelets various, usually with one or two fertile and some rudimentary sterile florets. The spikelets drop from the rachis of the inflorescence in little groups. A small tribe, mostly found in the dry regions of the Southwest. Inflorescence spikelike. Fig. 15. Pages 129, 130. Figure 15 Tribe VII. CHLORIDEAE. Spikelets with one to several florets, arranged in two rows on the under-side of one to many spikes. Fig. 16. Pages 131-143. Figure 16 Tribe VIII. PHALARIDEAE. Spikelets with enlarged glumes and one perfect terminal floret, with one or two staminate or sterile florets or little scales below it. The sterile florets fall attached to the perfect one. Disarticulation above the glumes. Fig. 17. Pages 144, 145. Figure 17 Tribe IX. ORYZEAE. Each spikelet consists of a single fertile floret. The glumes are lacking or reduced to minute ridges at the tip of the pedicel. Fig. 18. Pages 146, 147. Figure 18 11 HOW TO KNOW THE GRASSES Tribe X. ZIZANIEAE. Aquatic grasses; spikelets consisting of a single staminate or pistillate floret; glumes lacking or reduced to ridges at the tip of the pedicel. Fig. 19. Pages 147, 148. Figure 19 Subfamily PANICOIDEAE. Spikelets with a single perfect floret and a sterile one below it. The spikelet consists of a first glume (sometimes small or absent), a second glume as long as the whole spikelet, a sterile lemma, and a fertile floret. The spikelets are dorsally compressed and disarticulation is always below the glumes. Tribe XI. PANICEAE. The glumes and sterile lemma are thinner in texture than the fertile lemma and pcdea, which are hard or leathery. The first glume is usually much shorter than the second. Spikelets borne in panicles or racemes. Fig. 20. Pages 149-175. Figure 20 Tribe XII. ANDROPOGONEAE. Spikelets with two equal hardened glumes, which completely inclose the thin, delicate sterile lemma and fer- tile floret. Spikelets borne in racemes or spikes, a pair of them borne at each joint of the rachis. One spikelet of each pair is perfect and fertile, the other usually staminate, sterile, or rudimen- tary. Fig. 21. Pages 176-183. Figure 21 12 HOW TO KNOW THE GRASSES Tribe XIII. TRIPSACEAE. Stout, tall, corn-like plants, usually with solid stems. Spikelets are all uni- sexual, the staminate ones borne in one or more terminal racemes (sometimes forming a tassel), the pistillate ones borne in bony beads or rachis joints, or on cobs. The only common genera except Zea (corn) are Tripsacum (gama grass) and Job's Tears (Coix). Fig. 22. Pages 184, 185. Figure 22 SOME USEFUL BOOKS ON GRASSES HE following short Hst includes some of the principal books useful for identification or study of American grasses. The list is not intended to be complete, and some books which are old or unavailable have been omitted. You will find that a book on the grasses of your own state, or an adjacent one, will often make identification easier than such comprehensive works as Hitchcock's Manual, which covers a large and diverse area. Blomquist, H. L. 1948. The grasses of North Carolina, pp. vi plus 276. Keys, descriptions and illustrations. Duke Univ. Press. Dur- ham. Beetle, A. A. 1947. Distribution of the native grasses of California. Hilgardia 17: 309-357. Maps of distributions and discussions of ranges of the species; no keys or descriptions. Chase, Agnes. 1937. First book of grasses. Revised edition, pp. xiii plus 125. Good, well-illustrated explanations of spikelet struc- ture for the various tribes. W. A. Silveus, San Antonio, Tex. Core, E. L., E. E. Berkley, and H. A. Davis. 1944. West Virginia grasses. Bull. 313, West Va. Agric. Expt. Sta. pp. 96. Keys, descriptions, illustrations. Deam, C. C. 1929. Grasses of Indiana, pp. 356. Keys, descrip- tions, maps, illustrations. Pub. 82, Indiana Dept. of Conservation. IndianapoHs. Dore, W. G. and A. E. Roland. 1942. The grasses of Nova Scotia. Proc. Nova Scotia Instit. of Sci. XX: 177-288. Keys, discussions, illustrations, maps. Fassett, N. C. 1951. Grasses of Wisconsin, pp. 173. Keys, maps, illustrations. Univ. of Wisconsin Press. Madison. Featherly, H. I. 1946. Manual of the grasses of Oklahoma. Bull. 21, Okla. Agric. and Mechan. College, pp. 137. Keys, descriptions, illustrations. 13 HOW TO KNOW THE GRASSES Gates, F. C. 1937. Grasses in Kansas. Rept. of Kansas State Board of Agric, Vol. LV, No. 220-A. pp. 349. Keys, descriptions, illustra- tions of species, maps. Harrington, H. D. 1946. Grasses of Colorado, pp. 167, plus index. Keys and descriptions, no illustrations. Mimeographed. Colorado A. and M. College, Fort Collins. Hitchcock, A. S. 1936. The genera of grasses of the United States, with special reference to the economic species. U. S. Dept. of Agric. Bull. 772, revised ed. pp. 302. Keys to genera, illustrations, discus- sions of important species. Supt. of Documents. Hitchcock, A. S. 1951. Manual of the grasses of the United States. U. S. Dept. of Agric. Misc. Publ. 200, revised edition (by Agnes Chase), pp. 1051. Abundantly illustrated. This is a very important publication on American grasses, but rather large and complex for the beginner. Supt. of Documents, Washington, D. C. Mosher, Edna. 1918. The grasses of Illinois. 111. Agric. Expt. Sta. Bull. 205. pp. 261-425. Keys, descriptions, illustrations. Norton, J. B. S. 1930. Maryland grasses. Md. Agric. Expt. Sta. Bull. 323. Keys, brief descriptions, key to vegetative characteristics of grasses. Pohl, Richard W. 1947. A taxonomic study on the grasses of Penn- sylvania. American Midland NaturaHst 38: 513-604. Keys and habitat notes, no descriptions or illustrations. Pool, Raymond J. 1948. Marching with the grasses, pp. xii plus 210. This is a book on the economic botany of grasses. Not useful for identification of individual genera or species. Univ. of Nebraska Press. Lincoln. Silveus, W. A. 1933. Texas grasses, pp. xlvi plus 782. Illustrations, keys, and descriptions. Pub. by the author. San Antonio. U. S. Dept. of Agricuhure. 1948. GRASS: The yearbook of agricuhure 1948. Contains numerous articles on grasses, legumes, grasslands. One section is on common agricultural grasses. Illustrations. Supt. of Documents. Washington, D. C. U. S. Forest Service. 1937. Range plant handbook, pp. xxvi plus 512. One section on grasses. Illustrations, detailed notes on structure, uses by grazing animals, range, etc. No keys. Supt. of Docu- ments. Washington, D. C. 14 PICTURED-KEYS TO COMMON AMERICAN GRASSES la. Plants with woody perennial culms, one to many meters tall (bam- boos). Fig. 23. CANE Figure 23 Tribe I. BAMBUSEAE ATundinaria gigantea (Walt.) Chapm. Stems (canes) woody, perennial, reaching as much as 10 m. in height; plants rarely flowering. Cane grows in dense colonies, called canebrakes, in river bottomlands from Virginia to the Ohio Valley and southward to eastern Texas and Florida. The canes are used for fish poles, basketry, and in a vari- ety of other ways. The young shoots and leaves are eagerly taken by do- mestic animals. A smaller form of cane, with culms usually less than 2 m. tall, is called Arundinaria tecta (Walt.) Muhl. While cane is our only native bamboo, a number of other species are sometimes grown for ornament. Hardiest of these is Pseudosasa japonica, a small bushy bamboo reaching 2 — 3 m. tall, spreading by rhizomes and forming dense colonies. lb. Plants with non-woody annual culms, usually less than 2 m. tall 2 2a. Some or all of the spikelets inclosed in bony beads or spiny burs 3 2b. Spikelets not inclosed in beads or burs 6 3a. Pistillate spikelets only inclosed in smooth bony beads 4 3b. Perfect spikelets inclosed in burs covered with hooks or spines 5 15 HOW TO KNOW THE GRASSES 4a. Low, creeping perennial plants, rooting at the nodes; staminate and pistillate spike- lets on separate plants. Fig. 24 See Fig. 247 (Buchloe dactyloides) Figure 24 4b. Erect, coarse grasses; staminate spikelets at the tip of the inflorescence; bony pistillate portion at the base. Fig. 25 TRIBE XIII, TRIPSACEAE, page 184 Figure 25 5a. Spines of the burs hooked at the tips. . . see Fig. 244. (Tragus berteronianus) 5b. Spines of the burs straight, not hooked see Fig. 282. (Cenchrus pauciflorus) 6a. Spikelets falling from the plants in clusters of 2 — many, never singly 19 6b. Spikelets either falling singly or breaking up into florets and leav- ing the glumes behind on the plant 7 7a. Spikelets of two unlike kinds (one staminate and the other pistil- late) in the same or different inflorescences 8 7b. Spikelets alike and nearly always with perfect flowers, or some- times perfect and staminate or rudimentary ones borne to- gether 12 16 HOW TO KNOW THE GRASSES 8a. Plants aquatic; pistUlate spikelets never on cobs nor inclosed in bony rachis joints; staminate spikelets with a single flower; glumes absent or reduced to minute ridges. Fig. 26 TRIBE X, ZIZANIEAE, page 147 8b. Plants not aquatic 9 9a. Staminate and pistillate spikelets on the same or separate plants; pistillate spikelets not on a cob nor imbedded in bony rachis joints... 10 I Figure 26 9b. Staminate and pistillate spikelets on the same plant; pistillate spikelets on a cob or imbedded in bony joints of the rachis TRIBE XIIL TRIPSACEAE, page 184 10a. Pistillate spikelets with 3-awned lemmas, the staminate ownless; plants spreading by stolons, on dry soils see Fig. 48. fScIeropogon bTevUolius) 10b. Spikelets not awned 11 11a. Lemmas glabrous, stiff and leathery, with 9 — 11 faint nerves; plants of salty or alkali soil see Fig. 45. (Distichlis stricia) lib. Lemmas soft, papery, with 5 nerves, often with a cottony web at- tached to the callus see Fig. 146. (Poa aTachniiem) 17 HOW TO KNOW THE GRASSES 12a. Spikelets with only one perfect floret, sometimes with unlike stami- nate, empty, or rudimentary ones above or below it 13 12b. Spikelets with several perfect or pistillate florets 27 13a. Entire spikelets breaking from the plant when ripe. Fig. 27 14 Figure 27 13b. Spikelets when ripe breaking off above the glumes, leaving them on the plant. Fig. 28 23 Figvire 28 14a. Both glumes absent or reduced to minute ridges be- low the lemma and palea; spikelets strongly later- ally flattened, with strongly keeled lemma and palea. Fig. 29.... TRIBE IX, ORYZEAE, page 146 Figure 29 14b. At least one glume well developed; spikelets flat or roimd in cross section *^ 18 HOW TO KNOW THE GRASSES 15a. Spikelets laterally compressed or round in cross section (Fig. 30); no sterile flo- rets below the perfect ones 16 15b. Spikelets usually dorsally compressed (Fig. 31), consisting of a perfect floret and an empty lemma or staminate floret and two (rarely one) glumes below it 18 ^ K/ Figure 30 Figure 31 16a. Spikelets sessile or nearly so, borne along the lower sides of one to many spikes TRIBE VII, CHLORIDE AE, page 131 16b. Spikelets borne on pedicels in panicles, not exclusively on the lower sides of branches 17 17a. Spikelets with a single perfect floret and no sterile or rudimentary ones. Fig. 32 TRIBE V, AGROSTIDEAE, page 102 17b. Spikelets with two florets, the lower perfect and the upper staminate; both glumes longer than the florets see Fig. 190. (Holcus lanatus) Figure 32 18a. Glumes and sterile lemma soft and papery; first glume shorter than the spikelet; fertile lemma and palea stiff or leathery. Fig. 33 TRIBE XI, PANICEAE. page 149 Figure 33 19 HOW TO KNOW THE GRASSES 18b. Glumes thicker and stiifer than the delicate fertile lemma and palea; both glumes as long as the spikelet; spikelets paired, in racemes; one spikelet of each pair sessile or on a short pedicel, the other on a longer pedicel, some- times rudimentary. Fig. 34 ....TRIBE XII. ANDROPOGONEAE, page 176 Figure 34 19a. Spikelets borne in two rows along the lower side of the rachis of numerous spikes, which are borne in a raceme along a common rachis; spikes dropping from the rachis whole. Fig. 35 TRIBE VII, CHLORIDEAE, page 131 19b. Spikelets not borne in rows along the lower sides of the 1 — many spikes; spikes remaining whole or break- ing up into groups of spikelets or single spikelets. .20 X ^ ^ Figure 35 20a. Rachis breaking up into joints at maturity, each joint bearing 2 — 3 spikelets 22 20b. Rachis remaining intact, the groups of spikelets falling from it. .21 21a. Spikelets falling with a ring of long hairs attached see Fig. 284. (genus Pennisetum) 21b. Spikelets without a ring of hairs attached TRIBE VI, ZOYSIEAE, page 129 20 HOW TO KNOW THE GRASSES 22a. Each joint bearing 2 spikelets, usually one sessile and perfect and one pedicellate and staminate or sterile; glumes thick, the fertile lemma very thin and delicate TRIBE XII, ANDROPOGONEAE, page 176 22b. Each joint bearing 3 spikelets, the lateral two often sterile and reduced in size; lemmas not thin and delicate TRIBE III, HORDEAE, page 85 23a. Inflorescence a panicle, sometimes dense or contracted; each 25 spikelet on a pedicel, 23b. Inflorescence of one or more spikes, the spikelets sessile 24 24a. Spike single, terminal, with the spikelets borne in rows on opposite sides of the rachis. Fig. 36 TRIBE III, HORDEAE, page 85 Figure 36 24b. Spikes 1 — many, the spikelets arranged in two rows on the lower side of the rachis of each spike. Fig. 35 TRIBE VII, CHLORIDEAE, page 131 25a. Spikelets consisting of two (rarely one) glumes and a single perfect floret, no staminate or rudimentary ones with it. Fig. 37 TRIBE V, AGROSTIDEAE, page 102 Figure 37 25b. Spikelets with a perfect terminal floret and one or two staminate or rudimentary ones, often reduced to little scales, below it 26 21 HOW TO KNOW THE GRASSES 26a. Spikelets with two similar ilorets, the lower staminate and with a bent awn, the upper perfect and with a short straight awn ..see Fig. 179. (ATrhenatherum elatius) 26b. Spikelets with a single perfect floret and 1 or 2 unlike staminate or sterile florets or little scales borne below it ...Fig. 38. TRIBE VIIL PHALARIDEAE, page 144 Figure 38 27a. Spikelets borne in one or more spikes, sessile or rarely on short pedicels less than 1 mm. long 24 27b. Spikelets in open or dense panicles, each spikelet on a pedicel . . 28 28a. Glumes not reaching above the tip of the lowest floret; lemmas awnless or with one or more awns arising at the tip or between teeth. Fig. 39 TRIBE 11. FESTUCEAE, page 23 28b. Glumes reaching beyond the tip of the lowest floret and usually beyond the uppermost floret; lemmas awnless or with a single awn arising from the back or between two teeth. Fig. 40 ... 29 29a. Sheaths with imited edges TRIBE 11, FESTUCEAE, page 23 Figure 39 29b. Sheaths with overlapping edges. 30 30a. Lemmas with 3 prominent, conspicuously hairy nerves, all 3 extending into short awns — see Fig. 52 and following, (genus Tridens) 30b. Lemmas not as above. 31 Figure 40 31a. Tall stout grasses 1 — several m. tall; lemmas or rachilla joints covered with long straight hairs which conceal the spikelets TRIBE II, FESTUCEAE, page 23 31b. Grasses of small to moderate stature, seldom over 1 m. tall; lem- mas and rachilla joints smooth or hairy, but not concealed by long hairs TRIBE IV, AVENEAE, page 95 22 HOW TO KNOW THE GRASSES TRIBE II. FESTUCEAE la. Spikelets all similar in appearance (rarely unisexual) 2 lb. Spikelets of 2 diiierent kinds 8 2a. Lemmas undivided or with not more than 3 awns at the tips .... 3 2b. Lemmas bearing at the tip 9 or more awns, which are feathery on the lower half. Fig. 41. PAPPUS GRASS Enneapogon desvauxii Beauv. Figure 41 Perennial; tufted; culms 20 — 40 cm. long; panicles spikelike. Leaf blades threadlike, about 1 mm. wide. The lower sheaths are somewhat swollen, and contain cleistogamous spikelets which have nearly awnless lemmas. Several related species in the genus PappophoTum lack the feathery hairs on the awns. Dry desert hills and plains, from western Texas to Ari- zona and southward. Forage value low. September — October. Also called Pappophorum wiightii. 3a. Rachilla joints or backs of the lemmas bearing long straight hairs which give the spikelets a silky appearance; tall grasses, the culms 1—4 m. high 4 3b. Rachillas and lemmas not covered with hairs which cover the spikelet; (lemmas sometimes hairy on nerves or callus); plants usually 1.5 m. or less tall 5 23 HOW TO KNOW THE GRASSES 0 4a. Long hairs borne on the rachilla; lemmas smooth. Fig. 42. REED Phragmites communis Trin. Reed is a tall perennial grass, reaching 4 m. or more in height, with smooth, poHshed stems and long and very broad leaves. The plants spread widely by vigorous rhizomes, form- ing great colonies along the margins of streams and in marshes and ditch- es. In autumn the large panicles be- come very feathery because of the hairy rachillas. The lowermost floret of the spikelet is staminate or sterile. Reed is widespread in the United States and is also known from all of the continents of the world. Fossil rhizomes of reed have been found in Europe, making it one of the few grasses known from past geological ages. July — October. Figure 42 4b. Rachilla not hairy; lemmas covered with long hairs. Fig. 43. GIANT REED Arundo donax L. Perennial. This is one of the most spectacular of grasses of the tem- perate zone. The great culms reach a height of 6 m., and a thickness of 5 cm. or more. The plumelike panicles which are produced by well estabhshed clumps may reach a length of 60 cm. Altogether, the plants resemble bamboos closely, but the stems do not persist over winter. Giant reed is a native of Europe, but is cultivated and naturalized in our southern states, and has proved hardy in cultivation as far north as central Iowa. The tough rind of the culms is used to make clarinet reeds. Fall. Figure 43 24 HOW TO KNOW THE GRASSES 5a. Staminate and pistillate spikelets similar but on separate plants . . 6 5b. Spikelets all perfect 9 6a. Plants annual, spreading extensively by delicate stolons, forming flat mats on muddy ground .... 23a 6b. Plants perennial, spreading by rhizomes; cxilms erect, the plants not forming flat mats 7 7a. Lemmas pubescent or with a cottony web of hairs at the base. Fig. 44 110b Figure 44 7b. Lemmas glabrous; plants of salty or alkali soils. Fig. 45. SALT GRASS Distichlis stricia (Torr.) Rydb. Perennial; spreading by stiff, scaly rhi- zomes; plants 10 — 40 cm. tall. The salt grasses are coarse, stiff plants of saline or alkali flats in the drier parts of the western states and in the coastal salt marshes. D. sfricta is confined to the in- terior of the western United States. In desert areas, it is eaten readily by cattle, but it is seldom taken where more suc- culent forage is available. April — Sep- tember. Distichlis spicata (L.) Greene, a very sim- ilar species, grows in brackish marshes along our entire Atlantic, Gulf and Pacific Coasts. Figure 45 25 HOW TO KNOW THE GRASSES 8a. Spikelets unisexual, the pistillate ones with lemmas each bearing 3 long awns, the staminate ones awnless; stolon-bearing plants of the southwestern states. Fig. 46. BURRO GRASS Scleropogon brevUoUus Phil. Figure 46 Burro grass is a low perennial, 10 — 20 cm. tall, spreading by stolons and mak- ing patches. Staminate and pistillate inflorescences on the same or different plants. The inflorescences are small tufts of a few erect spikelets. Each pistillate spikelet has a number of florets, which are shed from the glumes as a unit, covered with numerous awns. Each lemma looks much like a floret of Aristida, with three long awns. The sharp awns and callus of the pistillate lemmas can penetrate hair, wool, and facial tissues of grazing animals. Bur- ro grass tends to replace more desirable grasses on overgrazed lands of the arid Southwest. Forage value very low. June — September. 8b. Spikelets perfect or sterile, the lemmas awnless or with single awns; tufted plants of humid areas; stolons lacking. Fig. 47. CRESTED DOGTAIL CynosuTus cristatus L. Figure 47 Perennial; tufted, culms 30 — 60 cm. tall. The sterile spikelets are paired with fertile ones in the same inflorescence. The sterile spike- let is made up of slender empty owned lem- mas. Inflorescence a dense, spikelike pani- cle. Dogtail is a European grass which has been imported for use in lawn and meadow seed mixtures. It is occasionally found in lawns, pastures and waste places in the east- ern states and also in the Pacific Northwest. Apparently it has httle value for forage. June — August. 26 HOW TO KNOW THE GRASSES 9a. Lemmas with 3 prominent nerves (the mid- rib and one on each side of it); nerves often hairy. Fig. 48 10 SIDE BACK Figure 48 9b. Lemmas with 5 or more nerves, which may be inconspicuous. Fig. 49 42 SIDE BACK Figure 49 10a. Inflorescence small, dense, with few spikelets, partially surround- ed by the leaves; small plants of the plains and deserts of the West 11 10b. Inflorescence an open or dense panicle which is supported above the leaves on a peduncle 12 11a. Lemmas long-hairy over the back; spikelets not concealed in leaf sheaths 15b lib. Lemmas long-hairy only on the margins; spikelets concealed in the upper sheaths; sprawling, mat-forming plants See Fig. 248. CMunroa squarrosa) 12a. Nerves or callus of the lemmas pubescent, 13 12b. Nerves and callus glabrous 19 13a. Nerves of lemmas conspicuously pubescent; plants lacking rhi- 14 zomes 27 HOW TO KNOW THE GRASSES 13b. Nerves of lemmas glcxbrous, the callus with a tuft of long hairs; plants with slender, elongated rhizomes. Fig. 50. BLOWOUT GRASS Rediieldia flexuosa (Thurb.) Vasey Perennial; culms 60 — 100 cm. tall; pani- cles large, pyramidal; leaf blades smooth and tough, elongated, inrolled. The spike- lets when mature are fan-shaped, with con- spicuous cottony tufts visible from the side. Because of the numerous long, slen- der rhizomes, blowout grass is able to keep pace with the shifting sands and eventually bind dunes into place. It is an important sand-binding grass on sandy plains from South Dakota to Oklahoma and Arizona. August — October. Figure 50 14a. Palea not fringed with long hairs; plants perennial 15 14b. Palea fringed with long hairs on its upper half; plants annual, with weak, shallow root systems. Fig. 51. Triplasis purpurea (Walt.) Chapm. Annual; tufted; culms 30 — 75 cm. long, erect or spreading. In late season, the herbage may become quite reddish. The small terminal inflorescence usually pro- trudes somewhat from the uppermost sheath, but the axillary panicles are con- cealed in the swollen sheaths and have cleistogamous spikelets. Common on san- dy lands. July — October. Figure 51 Triplasis ameiicana Beauv. is a similar species of the southeastern states. It is perennial and the lemmas have awns about as long as the body. 28 HOW TO KNOW THE GRASSES 15a. Spikelets in open or dense panicles which are borne above the leaves; plants without stolons 16 15b. Spikelets in dense, cottony tufts which are exceeded by clusters of threadlike leaves; plants low, spreading by stolons. Fig. 52. FLUFFGRASS Tridens pulchellus (H. B. K.) Hitch. Perennial; tufted at first, then spread- ing by short stolons; usually less than 15 cm. tall. The entire plant consists of a tuft of threadUke basal leaves, from which arise culms which have a single long internode and bear a cluster of spikelets and leaves at the summit. These culms soon bend over and root at the tip. This process may be repeat- ed until a mat of the plant is built up. Fluffgrass is found on thin soils, over- grazed lands, and deserts. Forage value negligible; usually regarded as an in- dicator of overgrazing. Also known as Triodia pulchella. April — October. Figure 52 16a. Panicles dense, the branches short and close to the rachis, with overlapping spikelets; spikelets not deep purple 17 16b. Panicles large and open, with spreading branches; spikelets deep reddish purple. Fig. 53. PURPLETOP Tridens Uavus (L.) Hitch. Perennial; tufted; culms 1 — 1.5 m. tall- panicles graceful and open, up to 35 cm. long; leaf blades smooth, flat, 3 — 10 mm. wide. The three nerves of the lemma pro- trude as Httle points. Open or partially shaded grassy places. Purpletop is eaten by livestock to some extent. It is attrac- tive and colorful and might be grown as an ornamental. Also known as Triodia flava. August — October. '^""^^ Tridens chapmani (Small) Chase is some- what similar. It has a stiffer and more open panicle. A circle of hairs extends completely around the base of each main and secondary panicle branch. Dry woods, mostly on the Coastal Plain, New Jersey to Texas, north to Iowa. 29 HOW TO KNOW THE GRASSES 17a. Spikelets hairy, variously colored 18 17b. Spikelets whitish, glabrous. Fig. 54. Tridens albescens (Vasey) Woot. and Stand. Perennial; tufted or rarely with rhizomes; culms 30 — 80 cm. tall; panicles spikelike; leaf blades elongated, 2 — 4 mm. wide, sometimes inrolled. This species may be confused with species of Eragrostis, but the fact that the lemma is split at the tip excludes it from that genus. The plants often grow in draws and around water holes. They are succulent and make good forage, but are seldom found in dense stands. April — October. Also known as Triodia albescens. Figure 54 18a. Panicle a dense ovoid tuft, 1 — 3 cm. long, containing usually less than 10 spikelets. Fig. 55. Tridens pilosus (Buckl.) Hitch. Perennial; tufted; 10 — 30 cm. tall. Most of the very narrow white-mar- gined leaves are at the base of the plants. The culm usually consists of a single intemode. The plants are very shallow rooted and easily pulled up. Found frequently on thin rocky soils and overgrazed ranges of the South- west. This species has Httle forage value and is generally regarded as an indicator of overgrazing. March — Oc- tober. Also known as Triodia pilosa. Figure 55 30 HOW TO KNOW THE GRASSES 18b. Panicle slender and spikelike, usually 5—15 cm. long, with more than 10 spikelets. Fig. 56. Tildens muticus (Torr.) Nash Figure 56 Perennial; tufted; culms 30 — 50 cm. tall. The spikelets often have a faint purplish hue before drying. Leaf blades very narrow, about 1 mm. wide. Overgrazed lands and dry rocky slopes. Forage value low. June — October. Also known as Triodia mutica. Tridens elongatus (Buckl.) Nash is very similar, but has leaf blades up to 3 — 4 mm. wide; plants 40 — 80 cm. tall; panicles 10 — 25 cm. long. Missouri to Texas and Arizona. 19a. Lemmas split at the tip. Fig. 57 17b 19b. Lemmas not split at the tip. 20 Figure 57 20a. Grain large, bottle-shaped, 5 — 6 mm. long, forcing the stiff, strong- ly-keeled lemma and the palea apart at maturity and protruding between them. Fig. 58. Diarrhena aznericana Beouv. Perennial; producing numerous scaly rhizomes; culms up to a meter in height; leaves mostly low on the culm, the blades 1 — 2 cm. wide, scabrous or hairy; panicle slender, with short erect branches, nodding, 10—30 cm. long. Spikelets 10 — 18 mm. long. Growing in scattered clumps in rich woods. The pecuHarly shaped grains are unique among our grasses. July — October. Figure 58 31 HOW TO KNOW THE GRASSES 20b. Grain not bottle-shaped nor forcing the floret open; not over 2 mm. long; lemmas not thick and stiff 21 21a. Spikelets with three or more florets; lemmas pointed, the veins converging; plants of wet or dry ground (NOTE: the Genus Era- grostis, which follows, is a difficult one. No entirely satisfactory key has ever been made for the species found in the U. S. The following keys are compiled from the best available) 22 21b. Spikelets with two florets; lemmas with wide blunt tips and paral- lel veins; plants aquatic. Fig. 59. BROOKGRASS Catabrosa aquatica (L.) Beauv. Perennial. The culms may lie on the ground and root at the nodes for half or more of their length of 10 — 50 cm. Panicles yellowish, 10 — 20 cm. long, open, pyramidal. Brookgrass is a soft, succu- lent grass of wet ground, found in the sub-arctic and at higher elevations in the western moimtains of the United States. The plants make excellent summer feed for livestock. Found also in northern Europe and Asia. Jiine — August. Figure 59 22a. Plants forming flat mats, the trailing culms rooting at the nodes . . 23 22b. Plants erect or with somewhat decumbent culms, but never root- ing at the nodes 24 32 HOW TO KNOW THE GRASSES 23a. Staminate and pistillate spikelets on separate plants; anthers about 1.5 — 2 mm. long; panicle dense. Fig. 60. Eragrosfis reptans (Michx.) Nees Annual; stoloniferous; only a few cm. tall, forming delicate, bright green turf along streams and on wet ground. Spikelets borne in dense panicles, resem- bling clover heads. Lemmas very strongly keeled. While the two sexes are similar in appearance, they can be told apart by the presence of anthers or stigmas pro- truding from the florets. Late sum- Figure 60 mer and fall. Forage value low. 23b. Spikelets all with perfect flowers; anthers minute, about 0.2 mm. long. Fig. 61. Eragrosfis hypnoides (Lam.) B. S. P. Annual; stoloniferous, forming low mats. The panicle is usually open. Lemmas very strongly keeled. The anthers are minute and nearly round, with a bulk of less than 1/50 that of those of E. reptans. Like most of its relatives, this plant is a warm weather grass, growing rapidly from mid- summer on. Stream banks and wet ground. Forage value low. July — September. Figure 61 '' 24a. Lemmas when mature dropping from the persistent rachilla of the spikelet; (this can be detected by pulling lemmas outward and downward) paleas usually remaining on the rachilla 36 24b. Lemmas not falling separately; spikelets disarticulating between the florets when mature 25 33 HOW TO KNOW THE GRASSES 25a. Pqleas without long iringing hairs, 26 25b. Poleas fringed with long straight hairs which nearly cover the spikelets. Fig. 62. - A. Eragrostis ciliaris (L.) R. Br. This delicate tufted annual grass grows 15 — 30 cm. tall, and bears dense cylindrical panicles, like those of the foxtail grasses, 3 — 10 cm. long. The tiny spikelets, only 2 — 4 mm. long, are immediately identifiable by the long, fringe-like cilia borne on the margins of the palea, which give a sort of spider-web appearance to the spikelets. River banks and open ground. Widespread in warm regions of the world. June — August. Figure 62 26a. Spikelets 3 — 15 mm. long. 27 26b. Spikelets 2 — 3 mm. long; panicle elongated, dense, narrowly cylin- drical. Fig. 63. Eragrostis glomerata (Walt.) Dewey Annual; tufted; plants a meter or less in height. E. glomerata produces a pro- fusion of slender, cylindrical panicles up to 50 cm. long, with strongly ascending branches. The plants flower from near groimd level to the very tip. The tiny spikelets have very thin, translucent lem- mas. At maturity the grains are visible through the lemmas. Banks of streams and ditches, alluvial woods. July — No- vember. Figure 63 34 HOW TO KNOW THE GRASSES 27a. Spikelets sessile or nearly so, strongly keeled and flattened, 28 27b. Spikelets on slender pedicels; lemmas keeled or rounded on the back 29 28a. Spikelets few. distant along the few elongated panicle branches, a sessile spikelet and a cottony tuft of hairs in the axil of each panicle branch. Fig. 64. EragTOstis sessilispica Buckl. Perennial; tufted; plants usually 20 — 40 cm. tall. This is a tumbleweed grass, the panicle breaking off and rolling with the wind when mature. The leaves are clus- tered in a short basal tuft. The panicle may reach as much as 40 cm. in length. The main axis is somewhat spiral; the branches are straight, stiff, and bear ses- sile spikelets. Dry sandy plains. Forage value apparently low. May — June. Figure 64 28b. Spikelets numerous, in a dense panicle; no sessile spikelets and cottony tufts in the axils. Fig. 65. Eragrostis oxylepis Terr. Perennial; wiry; tufted; plants 20 — 70 cm. tall; leaves 1 — 5 mm. wide, smooth except at the base of the blade. The spikelets are borne in one or more dense tufts along the axis or branches of the panicle. The spikelets often overlap like shingles. They usually have a reddish or bronzy color when ripe. Sandy or rocky open ground. Forage value apparently low. July — October. Al- so called E. secundiflora. Eragrostis beyrichii J. G. Smith is similar, but the spikelets are pale instead of bronzy. Oklahoma to Mexico. Figure 65 35 HOW TO KNOW THE GRASSES 29a. Panicle branches stiiily spreading; spikelets deep reddish purple; lemmas strongly keeled. Fig. 66. PURPLE LOVEGRASS Figure 66 Eragrostis spectabilis (Pursh) Steud. Perennial; tufted; erect or rarely spreading, up to 60 cm. tall. Purple lovegrass has a large, open, dome- shaped panicle which makes up about two-thirds of the height of the plant. The axils of the panicle branches and throats of the sheaths bear conspicu- ous tufts of white hair. The leaf sheaths may be smooth or hairy. This is one of our most widespread grasses on sandy open ground, and one of the most attractive. July — September. 29b. Panicle branches delicate, not stiffly spreading; lemmas not strong- ly keeled 30 30a Sheaths glabrous, or pubescent on only the upper edges, 31 30b. Sheaths pubescent along the edges, on the surface, and on the collar 32 31a. Lemmas 1.8 — 2.4 mm. long; panicle broad, ovoid. 35 36 HOW TO KNOW THE GRASSES 31b. Lemmas 2.4 — 3.4 mm. long; spikelets 4 mm. or more long; panicle elongated, ellipsoid. Fig. 67. SAND LOVEGRASS Eragrostis trichodes (Nutt.) Wood Perennial; tufted; 80—120 cm. tall. The open, cylindrical panicles may make up half the total height of the plant. The spikelets frequently have purplish florets and yellow glumes. Sandy plains and open woodlands. Sand lovegrass has high forage value, but has been virtually destroyed by overgrazing in many of the areas where it once abounded. August — September. EragrosUs curvula (see Fig. 69) some- times has smooth sheaths and might be keyed out here. It may be recognized by the lead-colored, short-pedicellate spikelets. Figure 67 32a. Sheaths and often blades bearing hairs, each of which arises from a little blister. Fig. 68. ... 33 32b. Hairs of sheaths not arising from little blisters 34 33a. Spikelets 5 — 10 mm. long; lemmas 2.4 — 3.4 mm. long 31b Figure 68 33b. Spikelets 2 — 5 mm. long; lemmas 2.0 — 2.4 mm. long. 35 34a. Panicle not over twice as long as wide; usually 15 cm. wide or wider 35 37 HOW TO KNOW THE GRASSES 34b. Panicle 3 times as long as wide; never over 12 cm. wide; culti- vated and sometimes escaping. Fig. 69. WEEPING LOVEGRASS Eragrostis curvula (Schrad.) Nees Figure 69 Perennial; tufted; 60—120 cm. tall, form- ing large round clumps. The leaves are long, drawn out to very fine drooping tips. The panicles are elongated and somewhat drooping; branches not bearing spikelets near the bases; spikelets dull straw colored or leaden gray. Native to South Africa, weeping lovegrass was first brought to the United States as an ornamental, but is now widely planted in the southern states as a forage grass for revegetating abandoned or eroded crop land. It makes excellent pasturage and can be used for hay. The seeds are about 1 mm. long, smooth, amber colored except for the blackish germ. Sum- mer. Eragrostis trichodes (Fig. 67) sometimes has hairy sheaths and may key out here. It may be recognized by the long-pedicellate, usually bronzy or yellowish spikelets. 35a. Lemmas 2.0 — 2.4 mm. long; larger leaf blades 5 — 10 mm. wide. Fig. 70. Eragrostis hirsuta (Michx.) Nees Perennial; tufted; plants be- coming a meter or more tall; panicles large, open, cylindri- cal, half the height of the plant. The leaves are wider than in most other species of this genus and taper to long fine points. The summits of the leaf sheaths (see figure) vary from extreme- ly hairy to glabrous. Dry soil, in open woods and fields. Sum- mer. Figure 70 38 HOW TO KNOW THE GRASSES 35b. Lemmas 1.8 — 2.2 mm. long; larger leaf blades 2 — 3 mm. wide. Fig. 71. Eragrostis intermedia Hitch. Perennial; tufted; reaching nearly a meter in height. This species has an open, dome-shaped panicle with slender delicate branchlets. The leaf blades are narrow, involute, and drawn out to slender tips; sheaths glabrous or the lower ones some- what hairy. Dry sandy open ground. June — September. Figure 71 36a. Plants perennial, usually 50—150 cm. tail, forming large clumps from hard, knotty bases; basal buds of next years growth present at flowering time go back to 27 36b. Plants annual, usually less than 50 cm. tall, from soft, shallow- rooted bases; no basal buds present at flowering time 37 37a. Spikelets with 2—4 (rarely 5) florets 38 37b. Spikelets with 6 — many florets (rarely 5 in starved plants) 39 39 HOW TO KNOW THE GRASSES 38a. Pedicels of lateral spikelets 3 — many times as long as the spike- lets; panicle large, diffuse, 2/3 or more of the total height of the plant; plants erect. Fig. 72. LACEGRASS Eragrostis capillaris (L.) Nees Lacegrass is a densely tufted annual, up to 50 cm. in height. Culms much branched at the base, the plants bear- ing numerous panicles; leaf sheaths somewhat hairy, especially at the throat; blades flat, hairy on the upper surface, 1 — 3 mm. wide; panicles open- cylindrical or elHptical, making up most of the height of the plants. Spikelets 2 — 3 mm. long, with 2 — 4 florets; glumes about 1 mm. long; lemmas about 1.5 mm. long. The minute grains are about 0.5 mm. long. Lacegrass is a common weed of open, dry situations on waste ground, in fields, and thin woods. August — September. Figure 72 38b. Pedicels oi lateral spikelets short, rarely more than twice the length of the spikelets; panicles about half the length of the sprawling plants. Fig. 73. Eragrostis frankii C. A. Mey. Annual. A weed of river banks and wet alluvial bottoms, E. frankii makes sprawling bushy tufts. The culms are seldom more than 25 cm. long. Leaf sheaths and blades usually smooth ex- cept at the throat. The ellipsoidal pani- cle is much denser than that of E. capil- laris, because of the shorter pedicels. August — September. Figure 73 40 HOW TO KNOW THE GRASSES 39a. Plants without glands on spikelets or branches; spikelets 2 mm. or less wide 40 39b. Plants bearing minute blister-like glands on the keels of the glumes and lemmas and the branches oi the panicle; spikelets 2.5 — 3.5 mm. wide when mature. Fig. 74. STINEGRASS Figure 74 Eragrostis cilianensis (All.) Link Annual; tufted; culms erect or some- what spreading; panicles ovoid or pyra- midal, rather dense. The keels of the glumes and lemmas bear tiny circular glands. Stinkgrass is a vigorous weedy annual, with a strong, musty odor when fresh. It may be poisonous to horses if eaten in large quantities. Frequent in fields, gardens, and dry, disturbed soil. Introduced from Europe and now very common throughout the United States. June — October. Also known as E. megastachya. A very similar species, E. poaeoides Beauv., has spikelets with glands on the keels of the lemmas also. The spikelets range from 1.3 — 2.0 mm. wide. It is less common than stinkgrass. In- troduced from Europe. 40a. Sheaths bearing a few long hairs on the margins at their sum- mits; paleas remaining on the rachilla 41 41 HOW TO KNOW THE GRASSES 40b. Upper sheaths (and usually the lower ones as well) lacking long hairs at their summits; panicle rather dense, the lower branches usually single, bearing 11 — 40 spikelets; paleas ialling from the rachilla with the lemmas. Fig. 75. Eragiostis multicaulis Steud. Weedy, tufted, annual, usually under 30 cm. tall. Spikelets 3 — 4 mm. long, us- ually with 4 — 8 florets. After the paleas fall, the minute zig-zag rachillas remain as the only evidence of the spikelets. This species grows mostly as a weed in cities in the northeastern states. Al- though introduced in the Americas, its homeland is not known with certainty, July — October. Also known as E. pere- grina. Figure 75 41a. Spikelets mostly lying closely oppressed to the panicle branches. Fig. 76. Eragrostis pectinacea (Michx.) Nees Weedy annual; tufted; culms usually 20 — 30 cm. tall; plants branching freely from the base, forming dense, erect tufts, Spikelets 5 — 8 mm. long. The manner in which the spikelets lie parallel to the panicle branches is characteris- tic. Frequent on dry roadsides, waste ground, and cultivated fields; one of the commonest weedy annual grasses. July — October. Figure 76 42 HOW TO KNOW THE GRASSES 41b. Splkelets when mature diverging strongly from the panicle branch- es; spikelets 0.7 — 1.4 mm. wide; lateral nerves of lemmas obscure. Fig. 77. Eragrostis pilosa (L.) Beauv. Annual; tufted; delicate; culms 10 — 50 cm. tall; panicles open, ellipsoidal. The tiny spikelets, 3 — 5 mm. long, stand out away from the main panicle branches on hair-like pedicels. Leaf blades 1 — 3 mm. wide, flat. Introduced from Europe. July — September. Figure 77 42a. Spikelets very strongly laterally compressed, the lemmas keeled 43 42b. Spikelets not strongly compressed, the lemmas rounded on the back 47 43a. Spikelets with 1 — 5 empty lemmas below the fertile ones; panicles drooping; spikelets large, 2 — 4 cm. long 44 43b. Spikelets without empty lemmas below the fertile ones; spikelets small or large ' 45 44a. Spikelets with 4 — 5 empty lemmas; leaf blades thick and involute, less than 1 cm. wide. Fig. 78. SEA OATS Uniola paniculata L. Perennial, producing strong rhizomes; plants up to 1 m. tall; panicles dense, nodding, 20 — 40 cm. long. The very flat spikelets of the Uniolas are strikingly ornamental. Sea oats inhabits the coastal sand dunes along the Atlantic and Gulf of Mexico and the West Indies. The panicles are frequently harvested and used for winter bouquets and display- window ornaments. Spikelets may be found on the plants at most seasons of the year. Figure 78 43 HOW TO KNOW THE GRASSES 44b. Spikelets with 1 empty lemma; leaf blades thin and flat, mostly 1 — 2 cm. wide. Fig. 79. Uniola latiiolia Michx. Perennial; producing rhizomes; plants 1 — 1.4 m. tall; panicles open and drooping, 10 — 20 cm. long. While similar to sea oats, this is a woodland species of rich soil in the south- eastern United States. It is highly ornamental and suitable for growing in shaded borders or wild gardens. Several other species of this genus with smaller spikelets also occur in the southeastern states. June — October. Figure 79 45a. Spikelets 2 — 4 cm. long, in open panicles; lemmas awned or awa- tipped between 2 teeth or below the apex 77 45b. Spikelets usually 1 cm. or less long; lemmas awnless or tapering into a short awn-tip 46 46a. Spikelets on pedicels, in open or contracted panicles; lemmas awnless; glumes not ciliate 104 46b. Spikelets nearly sessile, in dense, one-sided tufts at the ends of the few, long, stiff, panicle branches; glumes and lemmas ciliate on the keels; lemmas pointed or short-awned. Fig. 80. ORCHARD GRASS Dactylis glomerata L. Perennial; tufted; plants 60 — 120 cm. tall; herbage hght green; leaf blades 2 — 8 mm. wide. The panicle branches spread only at flowering time. The plants grow in large tussocks. They furnish both pas- turage and hay, and this species is rather important as a forage grass. It will toler- ate partial shade. Introduced from Europe. May — July. Figure 80 44 HOW TO KNOW THE GRASSES 47a. Lemmas longer than wide, their margins curled or folded in over the edges of the palea; florets making acute angles with the rachUla 48 47b. Lemmas nearly circular in outline, their margins not curled in; florets and glumes spreading at right angles to the rachilla. Fig. 81. QUAKING GRASS Briza minor L. Annual; tufted; 10—40 cm. tall. The species of Briza have very slender pedi- cels, which allow the drooping spike- lets to quiver in any slight breeze. Ligules 4 — 5 mm. long. This species and the next are occasionally grown for ornament and winter bouquets. April — May. Introduced from Europe. Briza media L. is similar, but has larg- er spikelets. The ligules are about 1.5 mm. long. New England to Michigan. Introduced from Europe. Figure 81 48a. Callus of the florets covered with prominent straight or cottony hairs 49 V 48b. Callus of the florets glabrous 51 49a. Callus hairy with straight spreading or erect hairs; lemmas owned or awnless. Fig. 82 .... 50 Figure 82 49b. Callus hairy with fine, crimped cottony hairs; lemmas awnless. Fig. 83 104 Figure 83 45 HOW TO KNOW THE GRASSES 50a. Lemmas irregularly toothed and cut at the apex; plants of wet ground or water. Fig. 84. SchoiocWoa fesiucacea (Willd.) Link Perennial; spreading by thick, elong- ated rhizomes; plants 1 — 1,5 m. tall; panicles open, 15 — 20 cm. long; leaf blades usually 5 — 10 mm. wide. This species is a plant of marshes and stream borders, where it often forms large col- onies along with sedges, rushes, and other kinds of aquatic grasses. Late Jime and early July. Furnishes some forage and marsh hay. Also known as Fluminea festucacea. Figure 84 50b. Lemmas owned between 2 teeth; plants of rocky woods. Fig. 85. Schizachne purpurascens (Torr.) Swallen Perennial; tufted; 50 — 100 cm. tall; sheaths with united edges; leaf blades narrowed at the base, 1 — 5 mm. wide; panicles about 10 cm. long, drooping. The glumes of the spikelets are usually purple. This is a rather delicate grass of rocky woodlands. It grows in scat- tered clumps and is seldom numerous. May — July. Also found in Japan and Siberia. Figure 85 51a. Upper florets of the spikelets sterile, often wrapped around each other and forming a club- or bell-shaped structure; (CARE!) sheaths with united edges; disarticulation above or below the glumes . . 52 46 HOW TO KNOW THE GRASSES 51b. Upper florets fertUe, the lemmas not enwrapping each otherr sheaths with overlapping or united edges; spikelets disarticulat- ing above the glumes 61 52a. Spikelets disarticulating below the glumes and falling entire at maturity 53 52b. Spikelets disarticulating above the glumes and between the flor- ets 56 53a. Rudimentary lemmas forming a pointed, cigar-shaped structure 54 53b. Rudimentary lemmas forming a blunt, club-shaped or bell-shaped structure 55 54a. Glumes reaching nearly to the tip of the spikelet; spikelets V- shaped. Fig. 86. Melica stricia Bolander Perennial; tufted; plants 15 — 60 cm. tall; panicle slender, almost unbranched, ra- ceme-like. All of the species of Melica have thin, translucent glumes and firmer lemmas. In this species, the glumes fre- quently have considerable purple colora- tion. Leaf blades scabrous, hairy on the top, 1 — 3 mm. wide. Rocky and gravelly slopes in the mountains. Late May — August. ^ Figure 86 47 HOW TO KNOW THE GRASSES 54b. Glumes less than 2/3 as long as the entire spikelet; spikelets narrow, cylindrical. Fig. 87. Melica poTieri Scribn. Perennial; tufted; 50 — 100 cm. tall; in- florescences slender and raceme-like, 15 — 20 cm. long, the branches ascending; spikelets mostly drooping to one side; pedicels hairy; sheaths smooth or scabrous, with united edges; leaf blades 2 — 5 mm. wide; spikelets green or brownish, not purple, 10 — 15 mm. long, with 4 — 5 florets; lemmas strongly-nerved, minutely scab- rous. Open woods and slopes, moist ground; 2000 — 3000 m. elevation. Midsum- mer— October. Var. laxa Boyle has spreading panicle branches 4 — 9 cm. long; glumes sometimes purple. Western Texas (Chisos Mts.) to Arizona. Figure 87 55a. Rudiment placed obliquely at the end of the rachilla; tips of fer- tile florets at the same height. Fig. 88. Melica znuiica Walt. Perennial; tufted; plants 60 — 100 cm. tall; panicles 10 — 20 cm. long, with a few simple spreading branches bearing drooping spikelets. Sheaths hairy or scabrous; leaf blades 2 — 5 mm. wide. Spikelets fan-shaped, 7 — 10 mm. long, usually with 2 fertile florets and a bell- shaped rudiment, tilteji sideways, at the end of the rachilla. This species, while seldom occurring in large stands, is the most widespread of the eastern Melica species. It grows in scattered stands in rocky woods. April — June. The name Melica refers to honey, but we do not know why Linnaeus appHed it to this genus. Figure 88 ^ 48 HOW TO KNOW THE GRASSES 55b. Rudiment placed straight on the end of the rachilla; tips of lower florets below that of the uppermost one. Fig. 89. Melica nitens (Scribn.) Hitch. Perennial; tufted; plants 50—120 cm. tall- leaf sheaths glabrous or scabrous; leaf blades 7 — 15 mm. wide; panicles 10 — 20 cm. long, with a few branches. The droop- ing spikelets are more slender than in the previous species and usually have 3 fertile florets. The rudiment is more slen- der and pointed than in Melica mutica. This species is probably more common than the previous one. The two are fre- quently confused but the position and shape of the rudiment should distinguish them. Scattered in rocky woods. Late April — June. Figure 89 56a. Lemmas without owns 57 56b. Lemmas bearing awns. Fig. 90. Me2ica smithii (Porter) Vasey Figure 90 Slender tufted perennial; plants 60 — 120 cm. tall; sheaths downwardly scab- rous; leaf blades soft, scabrous, 6 — 12 mm. wide. The panicles are very open, 12 — 25 cm. long, with slender spread- ing branches bearing spikelets at the tips. The spikelets are 18—20 mm. long, with 3 — 6 florets, and sometimes are purplish; awns are 3 — 5 mm. long. This slender woodland grass is found in moist forests. The occurrence in northern Michigan is the result of the cold post- glacial climate which once embraced that area. The plants resemble those of some of the perennial species of Bro- mus, from which they differ in the pres- ence of the rudiment. July — August. 49 HOW TO KNOW THE GRASSES 57a. Culms with bulbs at the bases 58 57b. Culms without bulbs at the bases 60 58a. Lemmas acute or obtuse, glabrous 59 58b. Lemmas tapering to an acuminate tip, pubescent. Fig. 91. Melica subulata (Griseb.) Scribn. Perennial; tufted; plants 60 — 125 cm. tall; panicles narrow, 10 — 15 cm. long. The culms of this species and several following have small, onion-like bulbs, about 1 cm. long, at their bases, because of which they are sometimes called onion grasses. Leaf blades usually 2 — 5 mm. wide. Moist forests. May -July. Figure 91 59a. First glume less than half as long as the spikelet; bulb attached to the crown of the plant by a thin stalk as much as 1 cm. long. Fig. 92. ONIONGRASS Melica spectabilis Scribn. Perennial; plants 30 — 100 cm. tall; pani- cle slender, 10 — 15 cm. long. This is a handsome species with somewhat inflat- ed spikelets, the lemmas purple-tipped. Leaf sheaths hairy; blades flat or rolled, 2 — 4 mm. wide. Gravelly mountain meadows and slopes. July — August. For- age value good. Figure 92 50 HOW TO KNOW THE GRASSES 59b. First glume more than half as long as the spikelet; bulbs attached directly to a thick knotty crown. Fig. 93. ONIONGRASS Melica bulbosa Geyer Figure 93 Perennial; plants 30 — 60 cm. tall; pani- cle narrow and stiff. Leaf sheaths and blades smooth or hairy; blades 2 — 4 mm. wide. This is perhaps the commonest western species in the genus. As the name impUes, the plants usually have prominent bulbs at the bases of the culms. Woods and open slopes. July — August. Forage value good. Melica iugax Boland. differs from the above species in having soft, thickish rachilla joints which turn tan and wrin- kle when dried. The rachilla of M. bulbosa is thin, smooth, and white. Pani- cles 8 — 15 cm. long, with short spread- ing or drooping branches. Dry ground, Washington to northern California and Nevada. Good forage for livestock and wild grazing animals. May — June. 60a. Spikelets with 3 or more fertile florets go back to 59b. 60b. Spikelets with 1 or 2 fertile florets. Fig. 94. Melica imperfecta Trin. Perennial; tufted or with decumbent culms; plants 25 — 80 cm. tall, bearing spreading panicles, 5 — 30 cm. long, of numerous small, often purplish spike- lets. In addition to the 1 or 2 fertile florets, there is a slender, yellowish rudi- ment which is 3 — 4 times as long as the very short rachilla joint which bears it. Gravelly soil. Good to excellent for- age. April — May. Figure 94 51 HOW TO KNOW THE GRASSES 61a. Nerves of lemmas running parallel to the tip, not meet- ing at the tip; lemmas usually rather broad; awnless. Fig. 95 62 61b. Nerves of lemmas converging at the acute apex; lemmas awnless or owned. Fig. 96 75 62a. Leaf sheaths with united edges, 62b. Leaf sheaths with free, overlapping edges 71 63a. Spikelets linear, usually 1 cm. or more long, round in cross sec- tion, on short pedicels in narrow, erect panicles 64 63b. Spikelets ovate or oblong, flattened, 7 mm. or less long; panicles with drooping or erect branches 66 64a. Lemmas obtuse; palea scarcely longer than the lemma 65 64b. Lemmas acute, the palea much longer than the lemma. Fig. 97. 30 Glyceria acutiflora Torr. Perennial; rhizome-bearing; plants 50 — 100 cm. tall; panicles slender, 15 — 36 cm. long. Wet soil, swamps, or shallow water. May- August. The species of Glyceria all live in wet places, frequently in very shallow water. Their spikelets are very fragile and break up at a touch when ripe. The plants are suc- culent and make good forage. Figure 97 52 HOW TO KNOW THE GRASSES 65a. Lemmas 2.5- Fig. 98. -4 mm. long, glabrous between the scabrous nerves. Figure 98 Glyceria borealis (Nash) Batch. Perennial; culms erect or decumbent; plants 60 — 100 cm. tall; panicles slender, erect, 20 — 40 cm, long; leaf blades 2 — 6 mm. wide; spikelets with 6 — 12 florets, 1 — 1.5 cm. long. The inflorescence of this species is similar to that of the next (Fig. 99). Shallow water and marshy- shores. June — September. This and the next species are very similar. The seeds of their close relatives in Europe are harvested from the water surface for hu- man food. 65b. Lemmas 4 — 5.5 mm. long, minutely scabrous between the nerves. Fig. 99. Glyceria septentrionalis Hitch. Perennial; culms spongy, 1 — 1.5 m. tall, erect; panicles 20 — 40 cm. long, with as- cending branches; leaf blades 10 — 20 cm. long, 4 — 8 mm. wide; foHage smooth or the leaf blades minutely scabrous; spikelets 1 — 2 cm. long, cylindrical, with 6 — 12 florets; lemmas about 4 mm. long. This is a tall, succulent grass of shallow water and wet places, probably yielding good forage. May — July. Glyceria fluitans (L.) R. Br. resembles the above but has lemmas 5 — 6 mm. long, usually purple below the tip. Newfound- land to New York; South Dakota; Eurasia. In eastern Europe, the florets and grains of this species are harvested from the water surface for human food, being made into soup and gruel. Figure 99 66a. Panicle narrow, erect, the branches strongly ascending. 67 66b. Panicle open, the branches drooping or spreading, 68 53 HOW TO KNOW THE GRASSES 67a. Lemmas about 3.5 mm. long; panicle dense, oblong, about 15 cm. or less long. Fig. 100. Glyceria obtusa (Muhl.) Trin. Perennial; culms erect or decumbent, 50 — 100 cm. tall; leaf blades flat or fold- ed; 2 — 6 mm. wide; spikelets with 4 — 7 florets, 4 — 7 mm. long. Glyceria ohtusa is a characteristic grass of the bogs of the Atlantic Coastal Plain, and found nowhere else. August — September. Figure 100 67b. Lemmas 2.0 — 2.7 mm. long; panicle slender, 15 — 36 cm. long. Fig. 101. Glyceria melicaria (Michx.) F. T. Hubb. Perennial; culms in small tufts, 60 — 100 cm. tall; leaf blades long and nar- row, rough, 2 — 5 mm. wide; spikelets with 3 — 4 florets, about 4 mm. long. The slender, arching culms of this species fringe woodland streams and puddles. July — August. Figure 101 68a. Spikelets oblong or ovate, mostly less than 2 mm. wide; lemmas thin, with conspicuous nerves 69 54 HOW TO KNOW THE GRASSES 68b. Spikelets broadly ovate. 2 — 5 mm. wide, with firm lemmas, the nerves not conspicuous. Fig. 102. Glyceria canadensis (Michx.) Trin. Perennial; tufted; plants 60 — 150 cm. tall; panicles 12 — 20 cm. long. Glyceria canadensis is one of the handsomest of grasses. The plump spikelets have a faint resemblance to snake rattles, hence the common name of "rattlesnake man- na." Bogs, swamps, along streamlets. July — August. Figure 102 69a. First glume 1 mm. or less long. 70 69b. First glume 1.4 mm. or more long. Fig. 103. Glyceria grandis S. Wats. Perennial; tufted; culms thick and tall, 1 — 1.5 m. high; leaf blades 6 — 12 mm. wide; spikelets 4 — 7 mm. long, with 4 — 7 florets; panicles 20 — 40 cm. long. This is a tall species, with large, dense, panicles. It is one of the commonest species of the genus within its range. Marshes and stream banks. June — August. Figure 103 55 HOW TO KNOW THE GRASSES 70a. Leaf blades 2 — 7 mm. wide, firm; culms usually 1 m. or less tall. Fig. 104. Glyceria striata (Lam.) Hitch. Perennial; forming large clumps; plants 30 — 100 cm. tall; foliage glabrous; leaf blades flat or folded; panicles drooping, pyramidal, 10 — 20 cm. long; spikelets 3 — 4 mm. long, usually with 3 — 7 florets, often purphsh. The spikelets shatter very readily when ripe. This is the most common and widespread of the American species of Glyceria. Usual- ly one will find a colony of it around every pond, runnel, or ditch, and it may also grow in moist woods. The plants provide good forage for domestic livestock and elk, espe- cially in later summer when the growth sites are drier. Sea level to 3300 m. elevation. May — August. Figure 104 70b. Leaf blades 6 — 12 mm. wide, soft; culms usually 1 — 3 m. tall. Fig. 105. Glyceria elaia (Nash) Hitch. Perennial; tufted; dark green; tall and stout, with spongy culms; panicles oblong, 15 — 30 cm. long, with spreading or droop- ing branches; foHage glabrous; leaf blades soft and thin; spikelets 4 — 6 mm. long, with 6 — 8 florets. This species looks Hke a larger version of the previous one, but it is restricted to the western states, where it is the most common and valuable forage species of the genus. Wet meadows, ponds, and moist woodlands. Eaten by all domestic livestock and elk; grazed pri- marily in late season when the herbage is less succulent and the habitats where it grows are less boggy. June — July. 56 Figure 105 HOW TO KNOW THE GRASSES 71a. Nerves of lemmas conspicuous; plants of wet, non-salty soils. .72 71b. Nerves of lemmas inconspicuous; plants of salty or alkali soils. .73 72a. Lemmas 5-nerved; plants found west of the 100th meridian. Fig. 106. Glyceria pauciiloia Presl Perennial; tufted; leaf blades usually 10 — 15 cm. long; 5 — 15 mm. wide; plants 50 — 120 cm. tall; panicles drooping, 10 — 20 cm. long; spikelets 4 — 5 mm. long, usu- ally with 5 — 6 florets. This and the next species depart from the usual in Glyceria by having split sheaths. The broad lem- mas have a purple line near their trans- lucent apex. Marshes, wet meadows, and shallow water, up to timber line. June — September. Figure 106 72b. Letnmas 7-nerved; plants found east of the Mississippi. Fig. 107. Glyceria pallida (Ton.) Trin. Figure 107 Perennial; plants weak and sprawHng; culms 30 — 100 cm. long; fohage glabrous; leaf sheaths spht; blades usually 4 — 8 mm. wide; panicles open, 5 — 15 cm. long; spike- lets usually 6 — 7 mm. long, with 4 — 7 florets; tips of lemmas thin, membranous, irregular; lemmas 2.5 — 3 mm. long. This species is found in cold, wet places, often in shallow water. May — June. Var. fernaldii Hitch, is a late-blooming form with very narrow leaf blades, 1 — 3 mm. wide. Wet places and shallow water; New- foundland to Pennsylvania, westward to Min- nesota and Wisconsin. 73a. Panicle pyramidal, open, the lower branches naked near their bases; plants widespread in the U. S 74 57 HOW TO KNOW THE GRASSES 73b. Panicle dense, short, the branches bearing spikelets to their bases; plants of the Atlantic Coast. Fig. 108. PuccinelUa iasciculata (Torr.) Bickn. Perennial; tufted; plants 20 — 50 cm. tall; panicles 5 — 15 cm. long, stiff. Leaf blades flat, folded, or rolled, 2 — 4 mm. wide. The species of Puccinellia grow on salty or alkaline wet soil. The lem- mas frequently have handsome purplish, bronzy, or golden bands below the apex. This species occurs in salt marshes along the Atlantic Coast. June — ? Figure 108 74a. Lower panicle branches bent downward; lemmas blunt, broadest near the apex. Fig. 109. Puccinellia distans (L.) Pari. Perennial; tufted; culms erect or decumbent, 20 — 50 cm. tall; panicle 5 — 15 cm. long. The stiffish, droop- ing lower panicle branches are char- acteristic. Leaf blades flat or rolled, usually 2 — 4 mm. wide. Moist soil. Introduced from Europe but now widespread in the United States. June — August. Figure 109 74b. Lower panicle branches not bent down; lemmas acute, broadest near the middle. Fig. 110. ALKALI GRASS Puccinellia airoides (Nutt.) Wats, and Coult. Perennial; tufted; plants 30 — 60 cm. tall; panicles 10 — 20 cm. long. Leaf blades flat or rolled, 1 — 3 mm. wide. Similar to the pre- ceding species, but with narrower lemmas. Native and widely dis- tributed in the West. Sometimes cultivated under the name of Zawadke AlkaU Grass. June — August. Also called P. nuttalliana. Figure 1 10 58 HOW TO KNOW THE GRASSES 75a. Lemma bearing an awn between two teeth, or from a point below the tip, or awnless but with a split tip. Fig. 1 1 1 . . 76 Figure 1 1 1 75b. Lemma awnless or bearing an awn at the very tip; tip of lemma never split 94 76a. Spikelets strongly laterally flattened, 2 — 4 cm. long; lemmas V- shaped in cross section 77 76b. Spikelets not strongly flattened, round in cross section before flowering; lemmas rounded on the back 78 77a. Lemmas awnless or with a short awn less than 2 mm. long. Fig. 112. RESCUE GRASS Bromus cathariicus Vahl Annual; tufted; culms up to 100 cm. long, erect or spreading; leaf sheaths and blades glab- rous or hairy, dark green; panicles open, up to 20 cm. long; spikelets 2 — 3 cm. long, with 6 — 12 florets; lemmas glabrous or rarely hairy, about 1.5 cm. long, much flattened and closely over- lapping. Rescue grass got its name from its winter annual habit, which makes it one of the earhest forage grasses in the South. It is planted in the fall for winter and spring pasture, but in many areas it has escaped from cultivation and is regarded as a wild plant. With good moisture, it makes lush, highly palatable forage. Heavy, rich soil, bottomlands. Native to South America. March — June. Figure 1 12 59 HOW TO KNOW THE GRASSES 77b. Lemmas bearing awns 5 — 15 mm. long. Fig. 113. MOUNTAIN BROME Bromus carinatus H. & A. Annual or biennial; tufted; plants 50 — 100 cm. tall or taller, vigorous and leafy; panicles 15 — 30 cm. long, with spreading or drooping branches; sheaths and leaf blades smooth or hairy; blades ranging from narrow and involute to broad and flat. A number of closely related and intergrad- 31 ing plants, sometimes recognized as separate spe- cies, are included here. These plants are com- mon on open ground and in thin woods in the western states and furnish a good deal of range forage. The foliage and the seed heads are eaten, the latter furnishing a good fattening ration for lambs. The seed of these plants is now available in commerce and the plants are used for range re- vegetation in the West. March — Jime. Figure 1 13 78a. Lemmas broad, rounded or tapered to the apex, the lateral teeth at the base of the awn not long and sharp 79 78b. Lemmas narrow, with a hard, sharp callus and long, sharp lateral teeth at the base of the awn 91 79a. First glume 1 -nerved, narrowly lanceolate. 80 79b. First glume 3 — 5-nerved, ovate or elliptical 84 80a. Plants tufted, without rhizomes; panicles mostly drooping; lemmas bearing well developed owns 81 60 HOW TO KNOW THE GRASSES 80b. Plants bearing rhizomes; panicles erect, with ascending branches; lemmas awnless or with very short awns, 1 — 2 mm. long. Fig. 114. SMOOTH BROME Bromus inermis Leyss. Perennial; 50 — 100 cm. tall; panicles 10—20 cm. long. Smooth brome, introduced from Eurasia, is one of our most successful forage grasses, and has been very widely planted in the U. S. for pasture and hay pro- duction. It frequently escapes to roadsides, ditches, and moist wooded areas. June — August. Bromus pumpellianus Scribn. is a closely related species, native to the western states from the Black Hills to Colorado and Alaska. It has rhizomes but the lemmas are hairy. It hybridizes with B. inermis. Figure 1 14 81a. Lemmas pubescent along the margins and lower part of the back, the central portion glabrous. Fig. 115. .82 81b. Lemmas pubescent across the back 83 82a. Ligule 3 — 5 mm. long; awns 5 mm. or more long; plants of the western states. Fig. 116. Bromus vulgaris (Hook.) Shear Perennial; tufted; plants slender; culms 80 — 120 cm. tall; Hgules prominent; leaf blades up to 12 mm. wide; panicles droop- ing, 10 — 15 cm. long; spikelets about 2.5 cm. long; lemmas usually 8 — 10 mm. long, hairy on the margins, glabrous or nearly so on the back; awns 5 — 8 mm. long. Moist rocky woods and canyons. July — August. Forms with nearly glabrous foU- age and lemmas are known. Figure 1 16 61 HOW TO KNOW THE GRASSES 82b. Ligule about 1 mm. long; awn 3 — 5 mm. long: plants widespread. Fig. 117. Bromus ciliatus L. Perennial; tufted; plants 70 — 120 cm. tall; pani- cles 15 — 25 cm. long, drooping. Leaf sheaths glab- rous or somewhat hairy; blades smooth or hairy, up to 1 cm. wide. This species has handsome fringed spikelets. It is one of the most widespread of the native woodland bromes in moist rocky or alluvial woods. It provides excellent forage in the western states. July — August. Figure 1 17 83a. Culms with 3 — 7 nodes; sheaths without auricles. Fig. 118. Bromus purgans L. Perennial; tufted, in small clumps; culms erect or leaning; plants usually 60 — 150 cm. tall; panicles open, drooping, usually 15 — 20 cm. long; leaf sheaths short- er than the internodes, hairy or rarely glabrous; leaf blades 5 — 17 mm. wide; lemmas rather uniformly hairy across the back. This is the commonest woodland brome in the eastern United States. It is to be found in nearly every moist woods. June — July. Forma glabriilorus Wiegand is a form of this spe- cies which has glabrous lemmas. It may be dis- tinguished from other similar woodland bromes by the anthers, which are 3 — 4.5 mm. long. Figure 1 1 8 62 HOW TO KNOW THE GRASSES 83b. Culms with 10 — 20 nodes, the sheaths longer than the intemodes, bearing pointed appendages (auricles) at the throat. Fig. 119. Btowms latiglumis (Shear) Hitch. Perennial; tufted; culms up to 2 m. tall; pani- 20 cles usually 15 — 25 cm. long, rather dense. Leaf sheaths longer than the internodes, hence over- lapping. This species blooms several weeks later than B. purgans. These two species fre- quently grow together. The sheaths are often covered with dense grayish wool. Alluvial bottomlands; prairies. July — September. Figure 1 19 84a. Panicle open, pyramid-shaped, erect or drooping 85 84b. Panicle dense, ovoid, erect, with short branches and overlapping spikelets 90 85a. Lemmas glabrous or scabrous 86 85b. Lemmas heavily pubescent 89 86a. Lemmas bearing awns, not broad or inflated 87 86b. Lemmas awnless or with minute own tips, very broad and in- flated. Fig. 120. RATTLESNAKE CHESS Bromus brizaeiormis F. & M. ■2D Annual; tufted; plants 3(!) — 60 cm. tall; panicles drooping, 5 — 15 cm. long. The odd, inflated spike- lets of this species look much like the rattlers of a rattlesnake. It is sometimes planted for ornament and is occasionally found naturalized in fields and waste ground in the western states and elsewhere. Introduced from Europe. June — August. Figure 120 63 HOW TO KNOW THE GRASSES 87a. Lemmas overlapping; rachilla not exposed; owns well developed; upper sheaths pubescent 88 87b. Margins of lemmas rolling inward at maturity, exposing the rachil- la; awns short, kinked; upper sheaths glabrous. Fig. 121. CHESS, CHEAT Bromus secalinus L. Annual; tuited; plants 30 — 60 cm. tall; panicles 7 — 12 cm. long. Chess is a common weed of road- sides and grainfields. Maturing quickly, the seeds may be harvested with wheat or other small grains and replanted elsewhere. Introduced from Europe. May — July. Old superstition claimed that cheat came from degenerate small grains, hence the name. Figure 121 88a. Mature spikelets 3 — 5 mm. wide; lower sheaths densely woolly with tangled or matted soft hairs. Fig. 122. JAPANESE BROME Bromus japonicus Thunb. Annual; tufted; plants 40 — 70 cm. tall; panicles drooping, with delicate flexuous branches. The awns may be straight or bent, depending upon their moisture content. Japanese brome was in- troduced from the Old World, and is now a very widespread weed of roadsides, fields, and waste ground. May — August. Bromus arvensis L., similar to this species, is very rare in this country, but is often confused with Japanese brome. B. arvensis has anthers 3 — 4 nun. long, those of B. japonicus being under 2 mm. long. Figure 122 64 HOW TO KNOW THE GRASSES 88b. Mature spikelets 5 — 8 mm. wide; lower sheaths covered with straight spreading stiii hairs. Fig. 123. Bromus commufafus Schrad. Annual; tufted; plants usually 30 — 100 cm. tall, freely branching from the base; foliage hairy; panicles open, pyramidal, usually 5 — 15 cm. long. In plants grow- ing on sterile dry soil, the inflorescence may be reduced to a raceme of a few spikelets. Such plants closely resemble B. racemosus (Fig. 127). This species is closely related to B. secalinus, from which it differs in the greater hairiness of the foliage and more overlapping florets. Along with B. japonicus and B. secalinus, this spe- cies is a widespread weed of fields and waste places. It is particularly common in the eastern and far western states, but apparently somewhat rare in the Middle West. Introduced from Europe. June — July. Figure 123 89a. Leaf blades 2 — 4 mm. wide, sparsely hairy; from North Dakota to western Texas and westward. Fig. 124. Bromus anomaius Rupr. Perennial; tufted; culms slender, 30 — 60 cm. tall- nodes hairy; sheaths somewhat hairy or glabrous; panicles small, drooping, usually 10 cm. long or shorter; spikelets few, drooping, densely hairy; first glume with 3 nerves, the second with 5; lemmas about 12 mm. long, the awns 2 — 4 mm. long. Bromus anomaius is widespread and common in the Rocky Mountain region, where it is regarded as a very valuable forage grass for all kinds of domestic Uvestock and for wild grazing animals. It grows in aspen, spruce, and pine forests and on open ground in meadows and parks, at elevations up to 3000 m. July — September. Var. lanitipes (Shear) Hitch, has woolly sheaths. Figure 124 65 HOW TO KNOW THE GRASSES 89b. Leaf blades 5 — 10 mm. wide, densely hairy; Minnesota and Iowa eastward. Fig. 125. WILD CHESS Bromus kalmii A. Gray Perennial; tufted; plants 50 — 100 cm. tall; panicles small, 5 — 10 cm. long, drooping. The lemmas are very conspicuously hairy. This and the preceding species are the only native perennial woodland spe- cies with 3-nerved first glumes. Roadsides and open woods. July — August. Figure 125 90a. Lemmas hairy. Fig. 126. Bromus mollis L Figure 1 26 Annual; tufted; plants 20 — 80 cm. tall; leaf sheaths and blades softly hairy; panicles stiff, dense, and erect, 5 — 10 cm. long; glumes and lem- mas hairy; first glume with 3 or 5 nerves, the sec- ond with 5 or 7; lemmas soft, with 7 nerves, usually 7 — 9 mm. long. This weedy species was introduced from Europe. It is found occasionally in the eastern and middlewestern states, but has become very abxmdant in the Pacific Coast states. It provides short-season spring forage, but because of its shal- low roots and annual habit, does not effectively protect the soil from erosion and is regarded as much inferior to Jhe perennial grasses which it re- places in overgrazed areas. April — June. Bromus moJiis hybridizes with the next species. 66 HOW TO KNOW THE GRASSES 90b. Lemmas glabrous. Fig. 127. Broxnus racemosus L. Annual; tufted; 20 — 80 cm. tall; panicle stiff, dense, erect. Bromus racemosus closely resembles the pre- ceding species and hybridizes with it. It is much less common in the eastern states, however. Starved plants of B. commutatus resemble B. racemosus but have more open panicles. This is a weedy annual of open ground, introduced from Europe. Low value, short- season spring forage. Spring. Figure 127 91a. Panicle open, the branches spreading or drooping. 92 91b. Panicle dense, erect. Fig. 128. Bromus rubens L. Annual; tufted; plants 15 — 40 cm. tall; panicles 4 — 8 cm. long. The Httle red- dish bushy panicles look like ragged bristle brushes. Common in the Intermountain Region and Pacific Coast States, on open dry ground. The awns may injure Hve- stock by piercing the facial tissues. Poor, scanty feed. March — June. Introduced from the Mediterranean area. Figure 128 92a. Second glume at least 12 mm. long; lemmas glabrous or sparsely stiff-hairy; owns 2 — 5 cm. long 93 67 HOW TO KNOW THE GRASSES 92b. Second glume 10 mm. long or shorter; lemmas usually softly pubescent; awns 1 — 2 cm. long. Fig. 129. DOWNY BROME Bromus fecforum L. Annual; tufted; plants 30 — 60 cm. tall; pani- cles drooping. 5 — 15 cm. long. The drooping, reddish panicles are rather ornamental, but the plants make poor, sparse feed and the sharp- pointed callus of the lemmas or the awns may penetrate the facial tissues of grazing animals. Of all the weedy European bromes, this is the commonest and most widespread. May — June. Melica smithii (see 56b) might be keyed here by the unwary. The plants are not hairy and it is a woodland perennial. Figure 129 93a. Awns 2 — 3 cm. long; first glume about 8 mm. long. Fig. 130. Bromus sterilis L. Annual; tufted; culms erect; plants 50 — 100 cm. tall; leaf sheaths softly hairy or nearly smooth; ligules prominent, mem- branous, with a lacerated edge; leaf blades soft, sparsely hairy or nearly glabrous; panicles 10 — 20 cm. long, open, with rather stiffly spreading or drooping branches; spikelets 2.5 — 3.5 cm. long, with 6 — 10 florets; lemmas 17 — 20 nmi. long, scabrous or stiff-pubescent; lateral teeth of the lem- ma about 2 mm. long. The stiff florets, provided with sharp calluses and stiff barbed awns, penetrate the facial tissues of grazing animals. Since the plants are shallow-rooted annuals, they soon dry up and their forage value becomes very low. While very widespread in the United States, B. sterilis is nowhere particularly common. Introduced from Europe. April -July. Figure 1 30 68 \ : ! HOW TO KNOW THE GRASSES 93b. Awns 3 — 5 cm. long; first glume 1.5 — 2 cm. long. Fig. 131. RIP-GUT GRASS Bromus rigidus Roth Annual; tufted; plant 40 — 70 cm. tall; leaf sheaths and blades coarsely and sparsely hairy; ligules 3 — 7 mm. long, membranous, with a lacerated mar- gin; panicles dense, with few spikelets. drooping, 7 — 15 cm. long, the lower branches only 1 — 2 cm. long. Some variants have longer lower panicle branches, hence a more open panicle. Spikelets usually with 5 — 7 florets; glumes glabrous; lem- mas scabrous or hairy; lateral teeth 3 — 5 mm. long; awns strong, barbed. Because of the sharp calluses and strong, stiff awns of the lemmas, the florets readily penetrate the soft facial tissues of grazing animals, inflicting bad puncture wounds around the nose, mouth, and eyes, especially on sheep. Frequently these become infected, resulting in pink eye, cancer eye, or other disease conditions. The common name, rip-gut grass, arises from these dan- gerous properties of the florets. Poor, short-season feed. Introduced from Europe; especially common in California; rare in the eastern states. April — August. Figure 131 94a. Lemmas awned or rarely awnless, tapering to sharp points; callus never bearing cottony hairs (see also Figs. 153 and 156) 95 94b. Lemmas awnless, not very sharp-pointed; callus frequently cov- ered with crimped, cottony hairs 104 95a. Plants perennial, with hard bases; leaves flat or rolled or folded; culms mostly 30 cm. tall or taller; stamens 3; florets opening at time of pollination. 96 69 HOW TO KNOW THE GRASSES 95b. Plants slender, annual, with shallow roots and hair-like leaves; culms usually less than 20 cm. tall; stamens usually 1; florets cleistogamous. Fig. 132. SIX WEEKS FESCUE Festuca octoilora Walt. Annual; tufted, seldom over 20 cm. tall. The leaves are borne mostly in a short basal tuft. The plants may be found on poor, usually sandy ground, throughout the United States. Forage value very low. The common name refers to the very short life span. This and a num- ber of small species of other genera, with similar growth habits, go by the name of "six weeks grasses." All may provide short-term emergency feed for range Hvestock after rcdns. April — July. Twelve other similar species of Festu- ca occur in parts of the U. S., but are much less common. They are some- times put in the genus Vulpia. Figure 132 96a. Leaf blades flat, soft, the larger ones more than 3 mm. wide; lemmas awnless or nearly so 97 96b. Leaf blades rolled or folded, firm, less than 3 mm. wide; lemmas owned or awnless -^^ 97a. Spikelets usually less than 10 mm. long, with 5 or fewer florets. .98 97b. Spikelets 8—18 mm. long, with 8 — 10 florets. Fig. 133. MEADOW FESCUE Festuca eJafior L. % % f \ Perermial; tufted; plants 50 — 120 cm. tall; leaf blades 4 — 8 mm. wide; panicle 10 — 20 cm. long, narrow cylindrical while flowering, but contracted and spikelike afterward. This species was introduced from Europe as a forage plant and has now become widely dispersed in meadows, pastures, roadsides and waste places in the northern states. For- age value good. June — July. Figure 133 70 HOW TO KNOW THE GRASSES 98a. Panicle branches short, erect, bearing spikelets nearly to their bases; plants of the Rocky Mts. Fig. 134. SPIKE FESCUE Hesperochloa kingii (S. Wats.) Rydb. Perennial; tufted or sometimes bearing rhizomes; plants 40 — 100 cm. tall; panicles 7 — 20 cm. long. Spike fescue has the stomi- note and pistillate spikelets on separate plants (dioecious). While the spikelets ore similar, the pistillate ones have well developed ovar- ies and abortive anthers, less than a milli- meter long, while the staminate ones have large anthers, about 4 mm. long, and no ovaries. Grazed by cattle and sheep. Dry mountains, at medium altitudes. May — Au- gust. Also called Festuca kingii. Figure 1 34 98b. Panicle branches slender, drooping; bearing spikelets only neca the outer ends; Dakotas to Texas and eastward. Fig. 135. NODDING FESCUE Festuca obtusa Biehler Pereimial; tufted; plants 50 — 100 cm. tall; panicles usually 15 — 20 cm. long. Nodding fescue is a species found in forests of the eastern half of the United States. The plants grow in small clumps, with somewhat spreading culms and drooping panicles. The spikelets shat- ter almost before reaching full size, mak- ing it difficult to find complete ones. May — September. A similar but rarer species is F. paia- doxa Desv., which bears 8 — 20 spike- lets, 4 — 6 mm. wide, on each lower pani- cle branch. Figure 135 99a. Lemmas awnless 100 99b. Lemmas bearing owns 2 mm. or more long 102 71 HOW TO KNOW THE GRASSES 100a. Ligule very short, less than 1 mm. long. 101 100b. Ligules 2 — 4 mm. long. Fig. 136. Festuca thurberi Vasey Perennial; densely tufted; culms rather stout, 60 — 100 cm. tall. The involute leaves are scabrous. Panicles 10 — 15 cm. long, the branches separate or paired, as much as 8 cm. long, and bearing spikelets only near their ends. The long ligule is characteristic. Dry rocky slopes, 2500 — 3500 m. . elevation. Forage value good. July — August. Figure 136 10 la. Leaves soft, green. Fig. 137. Festuca viridula Vasey Figure 137 Perennial; in dense tufts; culms 50 — 100 cm. tall; panicles open, 10 — 15 cm. long; branches mostly paired, 2 — 4 cm. long; leaf blades soft, folded or rolled; spikelets with 3 — 6 florets; lemmas 6 — 8 mm. long. The lemmas are softer than those of other spe- cies of fescue, and frequently hove some purpHsh coloration. Well drained soils in the spruce-fir forests near timberline; moun- tainsides, parks, and meadows. Green fes- cue is one of the best forage grasses of the Northwest. It is high in palatability and nu- tritive value, and is eaten throughout the grazing season by all classes of livestock, July — September. 72 HOW TO KNOW THE GRASSES 101b. Leaves stiif, bluish. Fig. 138. ARIZONA FESCUE; PINEGRASS Festuca arizonica Vasey Figure 138 Perennial; densely tufted; culms about 50 cm. tall; leaves stiff, pale, rather scabrous; panicles narrow, 8 — 20 cm. long, with one or two spreading branches at the base. Open pine forests, mountains of the Southwest. An important grazing grass, closely related to the more northerly F. idahoensis (Fig. 141). July — August. Festuca capillata Lam., commonly called HAIR FESCUE, is a much smaller plant, with spikelets under 5 mm. long, and short, spike- like panicles less than 5 cm. long. It occurs in lawns and waste places in the eastern states and westward to Illinois; Oregon. In- troduced from Europe. 102a. New leafy shoots arising within the old sheaths; plants forming dense tufts; old sheaths not reddish nor fibrous 103 102b. New leafy shoots breaking through the bases of the sheaths and spreading at the base, the plants hence forming loose turfs; old basal sheaths reddish brown, finally shredding into brownish threads. Fig. 139. RED FESCUE Festuca rubra L. Perennial; tufted; culms 40 — 100 cm. tall; panicle slender, the short branches ascending. Wet or dry ground; wide- spread in the eastern United States and in the western mountains. A number of forms of this species are used in lawn mixtures. Chewings fescue and creeping red fescue are among these. Red fescue is native in Europe, Asia, and North Africa as well as North America. Most of the occurrences in the eastern states seem to be intro- ductions, probably in lawn seed mix- tures. May — July. Figure 139 Fesfuca occidentaJis Hook, has somewhat similar culm bases but the awns are as long as the lemmas and the long, spreading panicle branches bear spikelets only near their tips. Northwestern states; northern Michigan and Ontario. 73 HOW TO KNOW THE GRASSES 103a. Leaf blades less than one half the culm length; panicles less than 10 cm. long; plants usually less than 30 cm. tall; wide- spread in the U. S. Fig. 140. SHEEP FESCUE Festuca ovina L. Perennial; tufted; 20 — 40 cm. toll, with a small, narrow panicle. Since the sterile leafy shoots (innovations) arise within the old sheaths, the plants form dense, bumpy tufts, making this spe- cies undesirable as a lawn grass. It frequently appears in old neglected lawns. In mass, the plants have a gray- ish-green color, but they do not turn brown during dry splls, as bluegrass does. Regarded as good forage in the western mountains. Native also to Europe and Asia. May — June. Var. biachyphylla (Schult.) Piper is a dwarf, high altitude form found above timber line in the western mountains, where it is important for grazing. Culms 5 — 20 cm. tall. Figure 140 103b. Leaf blades more than one half the culm length; plants 30 — 100 cm. tall; panicles 10 — 20 cm. long; in the western mts. Fig. 141. BLUEBUNCH FESCUE Festuca idahoensis Elmer Perennial; forming large tufts, the densely crowded slender culms up to a meter in height. The panicles are slender, 10 — 20 cm. long, usually with a single longer spreading lower branch. The leaves are rough and glaucous, but not as stiff as those of the closely related Arizona fescue (see 101b). Important as a range forage grass. Jime — August. Figure 141 104a. Plants producing rhizomes 105 104b. Plants tufted, without rhizomes 1 12 74 HOW TO KNOW THE GRASSES 105a. Culms round or nearly so in cross section (in pressed specimens, at least the nodes will be round) 106 105b. Culms strongly flattened, lens-shaped in cross section; spikelets never woolly. Fig. 142. CANADA BLUEGRASS Poa compressa L. Perennial; rhizome-bearing; panicles nar- row, 3 — 7 cm. long. The plants are rather wiry and form looser turf than Kentucky bluegrass. It is somewhat more drought resistant than the former species, but yields less forage. The plants bloom several weeks later than Kentucky bluegrass in the same locality. Mid-May — September. Introduced from Europe. Figure 142 106a. Lemmas completely glabrous or minutely scabrous, or with a small web of cottony hairs (Fig. 143) at- tached to the callus 107 106b. Lemmas pubescent on the keel or nerves, some- times with a web at the base also 108 Figure 143 107a. Panicles dense, with short branches, the spikelets overlapping; southern plains states or Southeast 1 10b 107b. Panicles open, the slender spreading branches naked at the base; western mountains 109b 108a. Lemmas pubescent only on the nerves; glabrous between them 109 75 HOW TO KNOW THE GRASSES 108b. Lemmas pubescent on the nerves and also between them near the base. Fig. 144. PLAINS BLUEGRASS Poa arida Vasey Perennial; producing rhizomes; culms 20 — 60 cm. tall; leaf blades borne mostly near the base of the plant, folded, 2 — 3 mm. wide; panicle dense, cylindrical, 2 — 10 cm. long, with short branches; spikelets 5 — 7 mm. long, the first glume with one nerve; anthers about 1.5 mm. long. Salty or alkaline meadows, up to 3000 m. elevation; an important forage grass on the Great Plains. Jime — ? Poa glaucifolia Scribn. & Will, is similar. The first glume has 3 nerves; anthers about 2.5 mm. long; panicles more open; herbage glaucous. Moist ground and open woods; Minn, to B. C., to Nev. and N. M. Figure 144 109a. Lemmas bearing a web of cottony hairs at the base; sheaths glabrous 110 109b. Lemmas without a web of hairs; lower sheaths glabrous or pu- bescent. Fig. 145. Poa neivosa (Hook.) Vasey Perennial; producing rhizomes; culms 30 — 70 cm. tall, in large, leafy tufts; leaf blades flat or folded; Hgules 1 — 2 mm. long; panicles open, usually 5 — 10 cm. long, with drooping branches which are naked at the base. The lemmas vary from entirely glabrous to hairy on the nerves or scaberulous. This species is highly vari- able in the hairiness of both sheaths and lemmas. In common with most of the na- tive and introduced bluegrasses, it is a valuable forage plant for domestic graz- ing animals and wild herbivores. Dry soil in open woods, intermediate altitudes. May — August. Figure 145 110a. Panicles open, the long branches naked at the bases Ill 76 >IOW TO KNOW THE GRASSES 110b. Panicles dense and compact, cylindrical, with overlapping spike- lets. Fig. 146. TEXAS BLUEGRASS Poa arachniiera Ton. Perennial; rhizomes present; plants producing leafy tufts; culms 30 — 75 cm. tall; leaf blades dark green, 2 — 4 mm. wide, scabrous on the upper surface; panicles lobed, 5 — 12 cm. long; spike- lets usually with 5 — 10 florets. The staminate and pistillate spikelets are on different plants, and the two kinds are quite different in appearance. The pis- tillate panicles are wooly due to the presence of copious cottony webs on the lemmas. The staminate inflorescences are not woolly, their lemmas having only small webs or none at all. The plants are succulent and very leafy; they provide excellent forage in winter and spring. Sometimes cultivated for for- age in the southeastern states. April — May. Figure 146 Poa macrantha Vasey is also dioecious. It is a sand-binder on the coastal dunes from Washington to northern California. The plants have extensive rhizomes and stolons. Spikelets large, about 12 mm. long; webs scanty. Ilia. Lower panicle branches mostly in pairs; lemmas 3.5 — 5.4 mm. long; anthers 2.0 — 3.5 mm. long. Fig. 147. Poa cuspidata Nutt. Perennial; rhizomes present; culms 30 — 50 cm. tall; plants growing in large tufts, with numerous long basal leaves nearly as long as the culms; leaf blades soft, 2 — 3 mm. wide; upper culm blades very short, rounded to an abrupt tip; panicles 7 — 12 cm. long, very open, pyramidal, the spike- lets all borne at the outer tips of the branches. This is the earhest blooming of all the native eastern grasses, usually i^^r*/ beginning to flower in early April in the ^^^ /Ns^^^ North. It is a plant of the central and 00^~~~^ southern Appalachians, where it is com- monly found on rocky banks and dry wooded hillsides. Unhke Kentucky blue- grass, which it resembles, it completely Figure 147 lacks aggressive or weedy tendencies. 77 HOW TO KNOW THE GRASSES 111b. Lower panicle branches mostly in whorls of 5; lemmas 2.4 — 3.6 mm. long; anthers 1.0 — 1.8 mm. long. Fig. 148. KENTUCKY BLUEGRASS Poa praiensis L. Perennial; rhizomes present; culms 30 — 100 cm. tall, in dense clumps with numerous sterile leafy shoots (innovations); panicles open, pyramidal, somewhat contracted after flowering. Kentucky bluegrass is one of our most widely distributed introduced grasses and is much used for lawns and pastures in the northern states. It is extensively natural- ized in pastures, prairies, roadsides, open woods and waste ground. April — July. In- troduced from Europe. Figure 148 1 12a. Lemmas bearing a web 113 112b. Lemmas glabrous or pubescent, but without a web 118 113a. Marginal nerves of lemmas pubescent 114 113b. Marginal nerves of lemmas glabrous 117 114a. Lemmas glabrous between the nerves; ligules of upper culm leaves 2.5 — 7 mm. long 115 114b. Lemmas pubescent between the nerves; ligules almost always less than 2 mm. long 116 78 HOW TO KNOW THE GRASSES 115a. Lemmas greenish-yellow, thin, with prominent intermediate nerves; sheaths usually scaberulous. Fig. 149. ROUGH STALK BLUEGRASS; TRIVIALIS Poa trivialis L. Perennial; tufted; culms 30 — 100 cm. tall, often somewhat bent or reclining at the base; panicles open, ovoid or pyramidal, the spike- lets clustered near the outer ends of the branches; lemmas glabrous or hairy on the lateral nerves. The plants are often found growing wild in wet places, and the seed is planted in lawn mixtures for shady places. May — June. Introduced from Europe. Figure 149 115b. Lemmas green, usually purple or bronzy at the tip, the inter- mediate nerves inconspicuous; sheaths smooth. Fig. 150. Poa palustris L. Perennial; plants slender, weak, with bent and recHning (decumbent) culm bases; pani- cles open, pyramidal, with slender, weak branches. The lemmas are usually purple and golden banded near the tip, making them very attractive under the lens. Wet meadows, stream banks, and moist woods; seldom numerous in one place. June — August. This species is native to both North America and Eurasia. Poa inferior Rydb. is very similar to the above, but has erect, tufted culms, small pani- cles less than 10 cm. long, and short ligules usually 1 mm. long or shorter. Across Cana- da and south to northern New England, Wis- consin, North Dakota and the high plains Figure 150 and western mountain states. 79 HOW TO KNOW THE GRASSES n.6a. Panicles cylindrical, 10 — 20 cm. long, the branches 3 — 6 in a whorl; lower branches drooping See P. sylvestris under P. alsodes, 117b. 116b. Panicles pyramidal, 5 — 10 cm. long, the branches 1 — 2 at a node, ascending See P. interior under P. palustris 115b. 117a. Upper ligules 3 — 7 mm. long; sheaths usually scaberulous; inter- mediate nerves oi lemmas conspicuous 1 15a 117b. Upper ligules 0.5 — 2 mm. long; sheaths smooth; intermediate nerves of lemmas inconspicuous. Fig. 151. Poa alsodes A. Gray Figure 151 Perennial; tufted; plants slender, 30 — 60 cm. tall, erect and graceful, with very open, delicate, cylindrical panicles, 10 — 25 cm. long and half as wide. The slender branches bear a few spikelets near their tips. Cool rocky woods or wooded flood plains in the northeastern states and the Appalachians. May — June. Poa sylvestris A. Gray is found also in rich woods and resembles this spe- cies, but has lemmas which are hairy between the nerves. New York to Wis- consin, southward to Florida and Texas. May — July. 118a. Lemmas pubescent between the nerves, the hairs often very short 119 118b. Lemmas glabrous between the nerves 120 80 HOW TO KNOW THE GRASSES 119a. Panicles very open, the branches slender, spreading, usually in pairs, bearing spikelets only near their outer ends; lemmas with conspicuous long hairs on their keels; eastern forested half of the U. S., to Michigan and Texas. Fig. 152. Poa autuznnalis Muhl. Perennial; tufted; plants delicate, 30 — 60 cm. tall; panicles 10 — 20 cm. long and nearly as wide, their branches very slender, bearing a few spikelets near the tips. Leaf blades 2 — 3 mm. wide, many at the base of the plants. The plants are not, as the name would seem to indicate, autumn blooming. Moist wood- lands. June. Figure 152 119b. Panicles usually dense, the branches bearing spikelets nearly to their bases; nerves of lemmas not bearing long hairs; western states, eastward to Minnesota and to the Dakotas. Fig. 153. Poa scabrella (Thurb.) Benth. Perennial; tufted; culms 50 — 100 cm. tall; pcrnicles slender, elongated, with ascending branches. This species and its relatives have lemmas covered, at least near their bases, with short crimped or oppressed hairs. A number of very closely related species or forms exist in this group, differ- ing mostly in the shape of the panicle. All are bunch grasses of the western states and are valuable forage grasses at lower and medium altitudes. March — August. Figure 153 81 HOW TO KNOW THE GRASSES 120a. Midnerve and lateral nerves of lemmas pubescent 121 120b. Lemmas glabrous or minutely scaberulous, not pubescent. .. 122 121a. Spikelets 6 — 8 mm. long; keels and marginal nerves of lemmas pubescent; intermediate nerves inconspicuous, not pubescent. Fig. 154v Poa iendlenana (Steud.) Vasey MUTTON GRASS Figure 154 Perennial; erect, densely tufted bunch grass; leaves mostly basal, stiff and sca- brous, folded or rolled, 1 — 2 mm. wide; culms 30 — 50 cm. tall, not much exceeding the basal leaves; panicles dense, oblong, 2 — 7 cm. long, the pale spikelets overlap- ping. The plants are dioecious but the spikelets of both sexes ore similar. Ligules short, less than 1 mm. long. Medium alti- tude hills and dry forests in the western mountains, from 2300 — 4000 m. It is re- garded as one of the best of the western forage grasses, especially for sheep. April —July. Poa Jongiiiguia Scribn. & Will, is very similar, but has ligules up to 5 — 7 mm. long. Range about the same as the preceding species. 121b. Spikelets 4 — 6 mm. long; keels, intermediate nerves, and mar- ginal nerves of lemmas conspicuous, usually all pubescent. Fig. 155. ANNUAL BLUEGRASS Poa annua L. Annual; tufted. The diminutive light green plants, usually less than 20 cm. tall, are soft, weak, and spreading. Panicles 3 — 7 cm. long, pyramidal, with short, spreading branches. The plants some- times grow in shallow water, then be- coming long, slender, and rooting at the nodes. This species begins growth in fall or early spring and blooms very early, and may die out when hot weather comes. Some blooming also occurs in fall. Lawns, paths, margins of water and open woods, roadsides. Introduced from Europe. Figure 155 82 HOW TO KNOW THE GRASSES 122a. Panicles short, ovoid, 2 — 8 cm. long; spikelets ovate in outline, about twice as long as wide; glumes and lemmas keeled; nerves of lemmas rather conspicuous 123 122b. Panicles elongated, cylindrical, 10 — 15 cm. long; spikelets little keeled, narrowly elliptical in outline, 3 or more times longer than wide, the glumes and lemmas rounded on the back; nerves of lemmas inconspicuous. Fig. 156. Poa nevadensis Vasey Perennial; tufted; culms erect, 50 — 100 cm. tall; sheaths scabrous; panicle narrow, elongated, 10 — 15 cm. long. This is one of a group of very similar bunchgrasses of the western mountain states. All have slender, elongated spikelets, whose lemmas are not keeled; lemmas glabrous and with inconspicuous nerves. They furnish excellent range forage for wild game animals and domestic Uvestock. Plains, dry meadows; open or partially wooded mountainsides, from near sea level up to 3700 m. elevation. May — September. Figure 156 123a. Leaf blades scabrous; ligules of culm leaves less than 2 mm. long. Fig. 157. Poa cusiclrii Vasey Perennial; culms in dense bunches, 20 — 60 cm. tall; basal leaf blades thread-like, very scabrous, about half the length of the culms; ligules usually under 1 mm. long; panicles 3 — 8 cm. long, dense, oblong, pale or some- what purpHsh. Rocky slopes and sagebrush plains, medium to high altitudes. May — July. Figure 157 83 HOW TO KNOW THE GRASSES 123b. Leai blades glabrous; ligules oi culm leaves 2— A mm. long. Fig. 158. Poa epilis Scribn. Figure 158 Perennial; culms in small tufts; plants 20 — 40 cm. tall; leaf blades of the culms short, flat, 2 — 3 mm. wide, their Ugules 2 — 4 mm. long; basal leaves long, folded or rolled; panicles on long, thin peduncles; panicles short, dense, oblong, 2 — 6 cm. long; spikelets about 5 mm. long, usually with 3 florets; lemmas 4 — 6 mm. long, some- times scaberulous. Poa epilis, sometimes called "skyline bluegrass," is an important high altitude forage grass, usually found above timberline on steep slopes and in mountain meadows. July — August. About five similar species are to be found at high altitudes in the western mountains, mostly above timberhne. They are all dwarf, rarely more than 20 cm. tall. 84 HOW TO KNOW THE GRASSES TRIBE III. HORDEAE la. One spikelet borne at each node of the rachis 2 lb. Two or more spikelets borne at some or all of the nodes of the rachis (some spikelets may be reduced to awned rudiments). .. 10 2a. Rachis not breaking up at maturity, the joints thin and flat 3 2b. Rachis breaking into individual joints at maturity; joints much thickened at their upper ends; spikes cylindrical. Fig. 159. GOATGRASS Aegilops cylindTica Host Annual; tufted; 40 — 60 cm. tall; much branched from the base, one plant bearing as many as 60 spikes; spikes 5 — 10 cm. long; joints of the rachis 6 — 8 mm. long, the spikelets slightly longer and fitting closely into the contour of the joints; spikelets glabrous or hairy, with 2 — 5 florets; lower spikelets nearly awnless, the up- per ones bearing awns up to 5 cm. long; glumes thick and stiff, bearing a pronounced tooth at one side of the awn. Goatgrass was presum- ably introduced into the Middle West in Turkey wheat brought to the United States by Russian immigrants in the 1870's. The plants are winter- annual, beginning growth in the fall and seed- ing out from May to July. They crowd out wheat when they are numerous. The seeds travel as contaminants in wheat seed. Aegiiops tTiuncialis L. is similar but has three awns on each glume. It is a bad weed on range land in California; introduced from Europe. Figure 159 5a. Spikelets placed flatwise against the rachis; both glumes present . . 4 85 HOW TO KNOW THE GRASSES 3b. Spikelets placed edgewise to the rachis; only the glume away from the rachis present. Fig. 160. RYEGRASS Lolium perenne L. Figure 160 Winter annual or short-lived perennial; culms 30 — 60 cm. tall; leaves dark green. The lemmas are awnless or nearly so. Ryegrass is much used in lawn seed mixtures, since the seed germinates rapidly and gives a green turf quick- ly, but the plants tend to die out when hot weather arrives. Lawns, fields, waste places, stream banks. Widely distributed through the U. S. This species and the variety listed below furnish good cool season forage. Introduced from Europe. May — July. Variety italicum Parn. (ANNUAL RYEGRASS). This is barely dis- tinct from the preceding species. It tends to have larger stature, more florets per spikelet, and owned lemmas, but there are many inter- mediates. Lolium temulentum L. (DARNEL). Darnel may be recognized by the very long glume, which exceeds the tip of the uppermost lemma. The lemmas are owned. Weed in grainfields and waste places, especially on the Pacific Coast and in the Southeast. This species is sometimes poisonous to livestock and human beings when eaten. Introduced from Europe. 4a. Spikelets with 3 or more florets; lemmas without stout bristles on the keels 5 4b. Spikelets with 2 florets; lemmas bearing short, stiff bristles along the keel; cultivated annual. Fig. 161. RYE Secaie cereale L. Rye resembles wheat in general appear- ance, but has a more slender spike. The lemmas are strongly V-shaped in cross section and have rows of vicious, upward- ly-pointed barbs along keel and margins. Rye culture is confined mostly to the northern states. The plants may be found scattered along roads and in waste places in regions where it is grown. Summer. In- troduced from Europe. Elongated blackish horns protruding from spikelets are ergot, a poisonous fungus used in medicine. Figure 161 86 HOW TO KNOW THE GRASSES 5a. Glumes lanceolate, acute, more than twice as long as wide; grain remaining inclosed by the lemma and palea; plants perennial .... 6 5b. Glumes broadly ovate, blunt, less than twice as long as wide; grain falling free of the lemma and palea; cultivated annual. Fig. 162. WHEAT Tnticum aestivum L. Figure 162 Wheat is the most extensively cultivated of the small grains and may be found growing in fields, waste places and roadsides as the result of seed being scattered accidentally. Some varieties of wheat have owned lemmas, others are awnless. Two primitive kinds of wheat, EMMER and SPELT, have spikes with a brittle rachis which breaks into individual joints at maturity. Both are occasionally grown as feed grains in dry regions. All introduced from the Old World. 6a. Plants producing creeping rhizomes 7 6b. Plants lacking rhizomes 8 7a. Leaves bluish glaucous, often inroUed; upper leaf surface fur- rowed, with 7 — 14 ridges across the width. Fig. 163. WESTERN WHEATGRASS Agropyron smithii Rydb. Perennial; culms 30 — 60 cm. tall- leaves heavily glaucous, so that patches of the plants have a conspicuous blue or silvery color when viewed from a dis- tance. Spikes slender, with erect spike- lets. This is essentially a plant of the mountain and plains states of the West, but is occasionally found farther east. In the western parts of its range it is a source of forage on moist alkaUne soil. Farther east, it grows on dry uplands, railroad embankments, etc. June — August. Figure 163 87 HOW TO KNOW THE GRASSES 7b. Leaves flat, usually green; upper surface of blades finely nerved, with 25 — 40 nerves across the width. Fig. 164. QUACKGRASS Agropyron repens (L.) Beauv. Perennial; with extensive creeping rhizomes; culms 50 — 100 cm. tall; leaves flat, green, often hairy on the upper surface; spike slen- der, with erect spikelets. Some of the plants have awned lemmas. Quackgrass is one of the worst grass weeds in the northern states. It produces good forage but is not intention- ally planted as a crop. Waste ground, road- sides, fields and meadows. May — July. In- troduced from Europe. 10 Figure 164 8a. Spikelets erect, pressed against the rachis; rachis joints at least 5 nun. long 9 8b. Spikelets spreading away from the rachis, overlapping; rachis joints about 1 mm. long . Fig. 185. CRESTED WHEATGRASS Agropyron deserforum (Fisch.) Schult. Perennial; tufted; culms 60—100 cm. tall. The strongly divergent spikelets distinguish this spe- cies from all others of this genus. Crested wheatgrass is a recent introduction from the Old World and has proved very useful for re- grassing abandoned crop lands and depleted ranges in the northern great plains states. A valuable forage species. June — August. Former- ly known as Agropyron cristatum. Fiaure 165 88 HOW TO KNOW THE GRASSES 9a. Lemmas awnless or with straight awns. Fig. 166. Agropyron trachycaulum (Link) Steud. Perennial; tufted; culms 50—100 cm. tall- spikes and spikelets slender; glumes conspicu- ously nerved. Awned and awnless forms oc- cur, often in the same stand of plants. This is an important forage species in the western mountains. Moist grassland and open woods. As here discussed, this species includes what are called A. pauciiloium (awnless) and A. suh- secundum fawned). June — September. Figure 166 9b. Lemmas with strongly bent awns. Fig. 167. BLUEBUNCH WHEATGRASS Agropyron spicatum (Pursh) S. & S. Perennial; tufted; cuhns 60 — 100 cm. tall. The spikes are slender and deU- cate. Sheaths smooth; blades 1 — 4 mm. wide, hairy on the upper surface. This species is one of the most abundant and important forage species of the northwestern states, and is readily eaten at all seasons and by all kinds of Hve- stock. Dry plains and open mountain slopes. May — August. Figure 167 10a. Spikelets with 1 floret; 3 spikelets at each node of the rachis, the lateral pair sometimes reduced to awns 11 10b. Spikelets with 2 or more florets, 2 or more spikelets at some or all nodes; all spikelets alike and fertile 13 11a. Rachis of spikes separating at maturity into individual joints, each bearing 3 spikelets; wild plants 12 89 HOW TO KNOW THE GRASSES lib. Rachis of spikes not separating into joints; cultivated annual. Fig. 168. BARLEY Horde um vuJgare L. Annual; tufted; culms usually 60 — 120 cm. tall; leaf blades flat, usually 5 — 15 mm. wide, with prominent auricles; spikes stiff and erect; spikelets 3 at each node of the rachis; each spikelet with a single fertile floret; glumes owned; lemma with a stout awn, usually 10 — 15 cm. long and very scabrous; rachilla pro- longed behind the palea as a small bristle. In the hooded barleys, the lemmas lack owns but bear min- ute abortive extra lemmas at their tips, in inverted position. Common strains of barley are 6-rowed, that is, all 3 spikelets at each node develop grains. There are also 2-rowed barleys, in which only the central spikelet of each trio develops a grain. Barley is cul- tivated for the grain, which is used for human food (pearl barley, cereals), for production of malt, and for livestock feed. It is grown principally in the Middle West and in the Great Valley of California. Stray plants may grow from scattered seed, but bar- ley is never found growing as a truly wild plant. Figure 1 68 12a. Awns mostly 5 — 8 cm. long; plants perennial. Fig. 169. FOXTAIL BARLEY Hordeum jubatum L. Figure- 169 Tufted; culms 30—60 cm. tall. The bushy spikes are 5 — 10 cm. long, and because of the spread- ing awns, about as wide. When still fresh, the awns often have a purplish or pink sheen . When the spikes are ripe, they break up into segments, each with a sharp-edged rachis joint at its base, and a trio of spikelets at its apex. Only the central spike- let is fertile, and the lateral two are reduced to long awns. The spike-segments are able to pene- trate clothing, wool, or flesh, causing puncture wounds, espe- 90 HOW TO KNOW THE GRASSES cially around the faces of animals. For this reason, foxtail barley is undesirable as a forage plant. Open ground, mostly in the mid- western and western states. May— August. 12b. Awns less than 2 cm. long; plants annual. Fig. 170. LITTLE BARLEY Hordeum pusiJlum Nutt. Annual; culms 10 — 35 cm. tall, in small tufts. Both glumes of the central spikelet and the inner one of each lateral spikelet are broadened above the base. The plants furnish some early season forage, but are rejected by livestock after the spikes emerge. Plams and open ground; com- (// mon in the Middle West and westward. February — July. Hordeum brachyantherum Nevski is simi- lar, but all of the glumes are narrow. West- ern mountain states, not common in the East. Introduced from Europe. Hordeum leporinum Link has thicker spikes which are nearly square in cross //b section and partially hidden in the upper- Figure 170 most sheath. Glumes of the central spike- let hairy on the edges. Mostly in the plains and mountain states. Introduced from Europe. 13a. Glumes nearly as long as the lowermost floret; spikelets erect, pressed against the rachis 14 13b. Glumes very short or lacking; spikelets spreading at right angles to the rachis. Fig. 171. BOTTLEBRUSH Hystrix paiula Moench Perennial in small lufts; culms slender, 60 — 120 cm. tall. Spikes 8—15 cm. long, very open, because of the spreading spike- lets. Leaf sheaths smooth or hairy; blades usually 7 — 15 mm. wide. This is a charac- teristic grass of damp woodlands through- out the eastern wooded sections of the country. In var. bigeloviana (Fern.) Deam, the lemmas are hairy. June — August. Figure 171 91 HOW TO KNOW THE GRASSES 14a. Rachis of spikes not breaking up when ripe 15 14b. Rachis oi spikes breaking up into individual joints, each bearing 2 spikelets, when ripe. Fig. 172. SQUIRRELTAIL Sitanion hystrix (Nutt.) J. G. Smith Perennial; tufted; culms 10 — 50 cm. tall, erect or spreading. The glumes bear one or two long, bent awns. The plants resemble Horde- um jubatum but the several florets per spikelet and two spikelets per node separate it from that spe- cies. The rachis joints bearing the awned spikelets, may pene- trate the facial parts of grazing animals, causing serious inflam- mation, pink eye, etc. Fair forage when seed heads are not present. Dry woods and grasslands. April — September. Sitanion jubatum J. G. Smith is similar but has three or more awns on each glume. Intermoimtain and Pacific Coast States. Figure 172 15a. Plants lacking rhizomes or rarely with short, thick ones. 15b. Plants producing slender creeping rhizomes; lig\ile 1 Fig. 173. 16 mm. long. Elyznus triiicoides Buckl. Perennial; culms usually 60 — 120 cm. tall, single or in small tufts, forming large patches by means of the long, slender rhizomes. The leaves are harsh, stiff, blu- ish-glaucous and often rolled. Damp or sahne soils, open ground. Sometimes part of the spike will have only a single spike- let at a node. Seven other species of Elymus produce extensive rhizomes. They are mostly plants of sand dunes along the oceans or in river valleys. May — August. Figure 173 92 HOW TO KNOW THE GRASSES 16a. Glumes very narrow, widest at the base and tapering upward, less than 1 mm. broad 17 16b. Glumes flattened, wider near the middle than at the base, the middle portions with several nerves 18 17a. Lemmas awnless or with awns shorter than the body of the lem- ma; plants of the Great Plains and western mountains and deserts. Fig. 174. GIANT WILD RYE Elymus cinereus Scribn. & Merr. Perennial; tufted; rarely with short, thick rhizomes; culms about 1 m. tall; leaves thick, stiff, flat or rolled; ligules 3 — 6 mm. long; spikes 15 — 30 cm. long. This is an important forage grass of dry plains, sand hills, and ditches in the western states. May — August. Elymus condensatus Presl is a very tall species, up to 3 m. high, with large, often compound spikes, up to 50 cm. long and 3 cm. thick. It grows along the Pacific sea beaches in California. Figure 174 17b. Lemmas with owns at least as long as the body; plants of wood- lands; eastern states and westward to Wyoming and Texas. Fig. 175. Elymus villosus Muhl. Perennial; tufted; culms slender, 60 — 100 cm. tall; leaf blades thin and dark green, their up- per surfaces velvety to the touch; spikes 5 — 12 cm. long; spikelets usually densely hairy; glumes 12 — 20 mm. long; lemmas 7 — 9 mm. long, with an awn 1 — 3 cm. long. Stream banks, thickets, and moist woods. June — August. Figure 175 93 HOW TO KNOW THE GRASSES 18a. Spikes loose and curved; awns strongly recurved when dry; bases of glumes thin and flat. Fig. 176. CANADA WILD RYE Elymus canadensis L. Figure 176 Perennial; tufted; culms erect or arching, bearing large, bristly spikes up to 25 cm. long. The lemmas are rather coarsely hairy. Canada wild rye is our most wide- spread species and is common over much of its range. It has been experimentally planted for forage production in the Middle West. Prairies, open ground, rocky banks and open woods. July — September. Elymus riparius Wiegand is very similar but has awns which are straight even when mature and dry. The lemmas are scabrous, not hairy as in E. canadensis. Quebec to North CaroHna, west to Nebras- ka and Arkansas. 18b. Spikes stiff and straight; awns straight; bases of glumes round in cross section, hard and smooth. Fig. 177. VIRGINIA WILD RYE Elymus virginicus L. Perennial; tufted; culms stiffly erect, 60 — 120 cm. tall; the base of the spike often hid- den in the uppermost sheath. The "bow- legged" glumes are a good mark of recogni- tion. Awned and awnless forms, as well as forms with smooth or hairy lemmas, are known. The plants are extremely variable in size and growth habit. The bases of the glumes are usually yellowish. Woods, thick- ets, stream banks, open ground. June — Sep- tember. Figure 177 94 HOW TO KNOW THE GRASSES TRIBE IV. AVENEAE la. Spikelets disarticulating above the glumes 2 lb. Spikelets disarticulating below the glumes, 12 2a. Lemmas with 9 awns each. . . .See Fig. 41 (Enneapogon desvauxu)» 2b. Lemmas with a single awn 3 3a. Spikelets (excluding awns) 9 mm. long or shorter 4 3b. Spikelets over 1 cm. long. 10 4a. Lemmas bearing an awn on the back (or if awnless, with slender hairy rachilla joints) 5 4b. Lemmas awnless or with a very short awn arising at the split tip of the lemma; rachilla joints very short. Fig. 178. JUNEGRASS Koeleria cristata (L.) Pers. Perennial; tufted; culms 30 — 60 cm. tall; panicles yellowish or silvery in color, nar- rowly cylindrical or somewhat lobed. At blooming time the branches spread but later close up again. Spikelets with 2 — 4 florets. Junegrass is one of the most wide- ly distributed of American grasses. Dry or sandy soil; prairies or open woods. Also found in Eurasia. June — September. Figure 178 5a. All florets alike and perfect; spikelets 2 — 6 mm. long 6 95 HOW TO KNOW THE GRASSES 5b. Lower floret staminate, with a bent, protruding awn; upper floret perfect, with a short straight awn; spikelets 7 — 9 mm. long. Fig. 179. TALL OATGRASS ArrhenatheTum elatius (L.) Mert. & Koch Perennial; tufted; culms 1 — 1.5 m. tall; leaf blades 5 — 10 mm. wide; panicles narrow and elongated, but with spreading short branches, 15 — 30 cm. long; glumes thin and somewhat translucent. Rarely both florets have bent awns. Tall oatgrass is cultivated in the north- ern states as a meadow grass and has freely- escaped to roadsides and waste ground. May — September. Introduced from Europe. Figure 1 79 6a. Awn attached near the base of the lemma 7 6b. Awn attached above the middle of the lemma or absent 8 7a. Rachilla prolonged beyond the base of the upper floret as a minute hairy bristle. Fig. 180. HAIRGRASS Deschampsia caespitosa (L.) Beauv. Perennial; tufted; culms slender, 60 — 120 cm. tall; leaves flat and sca- brous, mostly at the base of the plants, 1 — 4 mm. wide; panicles open, dehcate; spikelets often purple. The awns are nearly hidden within the glumes. The lemmas have several minute teeth at their tips. Bogs, wet ground, mountain meadows. An im- portant forage grass in the West. May -July. Deschampsia flexuosa (L.) Trin. is similar but the awns are strongly bent and protrude from the spikelets. Leaf blades fine and hair-like. Arc- ^'^""'^ ^^° tic North America, southward to Min- nesota and Michigan and southward in the Appalachian Mts. to Georgia; Arkansas and Oklahoma. 96 HOW TO KNOW THE GRASSES 7b. Rachilla not prolonged beyond the base of the upper floret. Fig. 181. SILVER HAIRGRASS Aira caryophyllea L. Annual; tufted; culms 10 — 35 cm. tall. The plants look like delicate little trees with open crowns. The silvery spikelets are closely clustered at the tips of the branches. Dry ground, mostly in the Atlantic and Pacific coastal regions. Introduced from Europe. April — July. Figure 181 8a. Spikelets disarticulating above the glumes 9 8b. Spikelets disarticulating below the glumes and falling entire. Fig. 182. ' Trfsefum pennsylvanicum (L.) Beauv. Perennial; culms slender and weak. 50—100 cm. tall; tufted. The spikelets are very flat and fall with about half of the pedicel at- tached. Meadows, swamps, and wet ground. May — June. TTisetum interruptum Buckl. has similar spikelets but a dense, spikehke panicle. Open dry plains, Texas to Colorado and Arizona. March — May. Figure 182 97 HOW TO KNOW THE GRASSES 9a. Awn short, concealed within the glumes, or absent. Fig. 183. Tiisetuzn woUii Vasey Perennial; tufted or sometimes with short rhizomes; culms 50 — 100 cm. tall; leaf blades flat, 2 — 4 mm. wide, scabrous on the upper surface; panicles dense, cylindrical, yellowish. An important forage grass in moist mountain meadows at mid-altitudes in the western mountains. July — September. Figure 183 9b. Awn protruding from the glumes, bent and twisted. Fig. 184. SPIKE TRISETUM Trisetum spicatum (L.) Richt. Perennial; tufted; culms 15 — 50 cm. tall; foliage smooth or finely hairy; panicles spikelike, dense, shaggy with many protruding awns, purplish or golden. An important forage grass at high altitudes, on slopes and in mountain meadows in the western mountains. The plants furnish good forage throughout the growing sea- son, especially for cattle and horses. June — August. Figure 184 10a. Awn attached between 2 teeth at the tip of the lemma; spikelets with 3 or more florets 11 98 HOW TO KNOW THE GRASSES WILD OATS 10b. Awn attached on the back of the lemma; spikelets with 2 or 3 florets. Fig. 185. Avena iatua L. Annual; culms usually 30 — 100 cm. tall, in small tufts; panicles open, up to 30 cm. long. The spikelets when ripe are open, bell-shaped, with conspicuous protruding bent awns. The scar at the base of the floret is circular and prominent and is usually called a "sucker mouth." Wild oats is distinguished by the hairy lemmas, prominent awns' and the sucker mouth. It is widely dispersed in the United States but is most common in the Pacific Coast States, where it is a prevalent weed and is sometimes cut for hay. May — August. ::io Figure 185 Avena sativa L. (CULTIVATED OATS) Fig. 186 differs from wild oats in having lemmas which are glabrous except on the callus, no sucker mouth, and weak, usually straight awns. Widely cultivated and growing from scattered seed on roadsides and waste ground. Figure 186 11a. Lemmas glabrous except for the hairy edges and callus; plants of the western mountains. Fig. 187. Danthonia caWornica Bolander Perennial; tufted; culms 30 — 80 cm. tall, tending to break at the joints. The panicle is small, consisting of 2 — 5 large spikelets on spreading pedicels. In this and other species of Danthonia, the lower sheaths may be swollen and contain slender, much distorted cleistogamous spikelets called "cleistogenes." The culms break off just below the node where a cleistogene is present. Meadows and open woods. Of some value for forage. May — August. Danthonia intermedia Vasey has the few spikelets borne in a dense, tuft-Hke panicle, 2 — 5 cm long. Arctic North America, south- ward to Michigan and at high altitudes in Grazed by livestock. July — September. Figure 187 western states. 99 HOW TO KNOW THE GRASSES lib. Lemmas hairy on the back as well as the edges; plants wide- spread in the United States. Fig. 188. POVERTY OATGRASS Danthonia spicata (L.) Beauv. Figure 188 Perennial; tufted; culms usually 20 — 50 cm. tall. Most of the short, curly leaves are borne in a basal tuft. Their Ugules are under 1 mm. long. Panicles short, 2 — 5 cm. long, with ascending branches. Poverty oats makes gray-green mats or sods on dry, sterile soils in the open or in thin woods. Forage value very low. Cleisto- genes may be present, as in D. californica. May — September. Danthonia compiessa Austin has pani- cles with spreading branches. The ligules of the lower leaves are 2 — 5 mm. long. Open ground and in moist or dry woods, mostly in the Appalachian Mountains; Que- bec to Georgia. June — July. 12a. One or both lemmas with awns; glumes similar in shape 13 12b. Lemmas without awns; first glume linear; second glume obovate, very broad. Fig. 189. WEDGEGRASS SphenophoJis obtusata (Michx.) Scribn. Perennial; tufted; culms 30 — 100 cm. tall; panicles dense and cylindrical, the branches spreading somewhat at flow- ering time. The peculiarly shaped glumes are the most characteristic thing about the wedgegrasses. In this spe- cies, the second glume is 2 — 2.5 times longer than its folded width. Open ground, thin woods, wet spots. Suc- culent and probably good feed, but not occurring in dense stands. May — August. Sphenopholis intermedia Rydb. has a looser, more open panicle; the second glume is 3 — 4 times longer than the folded width. Throughout the United ^'^"^'^ ^^^ States and southern Canada. May— July. Sphenopholis nitida (Biehler) Scribn. has a slender, open panicle. The upper lemma of each spikelet is visibly scabrous under a lens. Woods, eastern states to IlHnois and Texas. 100 HOW TO KNOW THE GRASSES 13a. Spikelets disarticulating in the pedicel, falling with the stub of the pedicel attached See Fig. 182 (Trisetuxn pennsylvanicum) 13b. Spikelets disarticulating just below the hairy glumes. Fig. 190. VELVET GRASS Holcus lanatus L. Perennial; tufted; culms 30 — 60 cm. tall; panicles elliptical, closely flowered. The spikelets have an awnless perfect lower floret and a staminate second floret with a short awn. The entire plant is softly velvety to the touch. Open moist ground, meadows, thickets. Velvet grass was imported for for- age but is rarely cultivated now. The plant has been known to kill Hvestock under some conditions. Forage value low. Introduced from Europe. June — August. Figure 190 101 HOW TO KNOW THE GRASSES TRIBE V. AGROSTIDEAE la. Spikelets disarticulating below the glumes and falling whole.... 2 lb. Spikelets disarticulating above the glumes, the floret falling 8 2a. Glumes with awns or protruding midribs 3 2b. Glumes without awns; midrib not protruding 5 3a. Both glumes with single awns; floret smooth and shining 4 3b. First glume with 2 or 3 awns; floret hairy. Fig. 191. WOLFTAIL LycuTus pbleoides H. B. K. Perennial; tufted; culms 20 — 60 cm. tall. The dense, spikelike, bristly panicles are usually gray in color. The spikelets fall in pairs, one of each pair being on a longer stalk than the other. The lower spikelet is staminate and the upper one perfect. Open brushy hillsides and ponderosa pine forests, 1400—2600 m. elevation. A valu- able forage grass, grazed especially in spring. July — September. Figure 191 4a. Awn straight and stiff, shorter than the lemma 25a 102 HOW TO KNOW THE GRASSES 4b. Awn fine and delicate, about 3 — 4 times as long as the lemma; spikelets 2 mm. long. Fig. 192. RABBITFOOT GRASS PoJypogon monspeJiensis (L.) Desf. Annual; tufted; usually 15 — 50 cm. tall; pani- cles dense, often somewhat lobed, densely covered with soft, silky yellowish awns. Rab- bitfoot grass is rather widely distributed in the United States, but is most common in the West, at low altitudes. Frequently found on seepy wet ground around springs or on banks of streams. Weedy; forage value low. May — October. Introduced from Europe. Figure 192 5a. Panicle dense, cylindrical and spikelike 6 5b. Panicle open, with spreading or drooping branches 7 6a. Spikelets about 5 mm. long; panicles 7 — 10 mm. in diameter; awns protruding. Fig. 193. MEADOW FOXTAIL Aiopecurus piatensis L. Perennial; tufted; culms 30 — 80 cm. tall. The panicles resemble those of timothy but the lemmas have protruding bent awns and the spikelets fall off at a touch when ripe. This genus is one of very few having unit- ed glumes. Meadow foxtail is sometimes cultivated as a forage grass in the north- ern states and found growing wild in meadows and waste ground. May — lune. Introduced from Europe. Figure 193 103 HOW TO KNOW THE GRASSES 6b. Spikelets 2 — 3 mm. long; panicles 4 — 5 mm. in diameter; awns con- cealed in the glumes. Fig. 194. AlopecuTus aequalis Sobol. Perennial; culms weak and sprawling. 15 — 60 cm. long; leaf blades 1 — 4 mm. wide; panicles cylindrical, shattering very readily; 2 — 7 cm. long. The plants are frequent on wet ground in swamps or along small streams. Succulent and probably good forage. May — June. Figure 194 7a. Glumes about 1/3 as long as the floret; cultivated annual; aquatic (Rice). See Fig 276. (Oryza sativa). 7b. Glumes about as long as the floret; wild plants, not aquatic. Fig. 195. WOODREED Cinna aiundinacea L. Perennial; culms in small tufts, 100 — 150 cm. tall; panicles large, 15 — 30 cm. long, drooping, the very flat spikelets shining, over- lapping. The leaves are sometimes over 1 cm. wide. This common woodland grass is foimd in moist forests. August — October. Cinna latifolia (Trevir.) Griseb. has smaller spikelets, less than 4 mm. long. Arctic Ameri- ca, southward through most of the United States except the southeastern states. Figure 195 104 HOW TO KNOW THE GRASSES 8a. Edges of leai sheaths united. See Fig. 94 (Melica imperiecta). 8b. Edges of leaf sheaths overlapping, not united 9 9a. Floret not dorsally compressed; a;vn present or absent. 10 9b. Floret dorsally compressed, the lemma and palea stiff, smooth and shining; awn absent. Fig. 196. Milium eUusum L. Perennial; culms in small tufts, up to 150 cm. tall. Foliage smooth, the leaf blades 8 — 15 mm. wide. The panicles are 10 — 20 cm. long, very open, cylindrical, with short droop- ing branches. The dorsally compressed floret greatly resembles that of species of Panicum, but the disarticulation above the glumes places it with the Agrostideae. Cool, moist woods. May — July. Figure 196 10a. Floret hard, round in cross section, with faint nerves; awn usually present; callus pointed, hairy. Fig. 198V4 11 Figure 1961/4 10b. Floret soft or leathery, usually more or less flat- tened and with evident nerves; callus not sharp pointed, either glabrous or hairy. Fig. 196V2....23 11a. Lemma with 3 awns, the lateral two often short. .12 Figure 196V2 lib. Lemma with a single awn or none 15 105 HOW TO KNOW THE GRASSES 12a. Central awn spirally coiled at the base, 13 12b. Central awn not coiled 14 1 3a. Glumes about equal in length; lateral awns about Va as long as the central one. Fig. 197. Aristida dichotoma Michx. Annual; tufted, in small, shallowly-rooted clumps; culms 20 — 40 cm. tall. The panicles are very slender, almost racemose. The spe- cies of Aristida are sometimes called wire- grasses or needlegrasses. They are typically grasses of depleted ranges or poor, sterile soils. This species is found on dry sandy or rocky open ground or in open sterile woods. Forage value negligible. August — October. Figure 197 13b. Glumes imequal, the first V2 to ^^ as long as the second. Fig. 198. Aristida basiramea Engelm. Annual; culms in small tufts, 30 — 50 cm. tall; leaf blades harsh, 1 — 2 mm, wide; panicles slender, raceme-Uke, 5 — 10 cm. long, at the tips of the culms and in axils of the upper leaf sheaths. Dry sterile soil, open ground. August — October. 10 - Var. curtissii (Gray) Shinners has very short lateral awns, 2 — 4 mm. long. Penn- sylvania and Virginia to Wisconsin, Wyoming, Colorado and Arkansas. Figure 198 106 HOW TO KNOW THE GRASSES 14a. Glumes about equal, 2 — 3 cm. long; lemma about 2 cm. long. Fig. 199. Aristida oligantha Michx. Annual; tufted; culms much branched, 30 — 50 cm. tall; leaf blades narrow, usu- ally under 1 mm, wide; panicles 10 — 20 cm. long; glumes nearly equal, 2 — 3 cm. long, sometimes 3-cleft at the tip; awns 4 — 7 cm. long, spreading, about equal in length. The plants are wiry and almost leafless, most of the height being the bristly inflorescences. The sharp-point- ed, 3-awned florets of this and other spe- cies of Aiistida are great "crawlers." The pointed and backwardly-barbed cal- lus penetrates hair or clothing easily, and every movement of the body of the host results in the floret digging in deeper, aided by the scabrous awns. Forage value negligible. Dry open ground. August — October. Figure 199 14b. Glumes unequal, the first about 1 cm. long, the second twice as long; lemma 12 — 15 mm. long. Fig. 200. DOGTOWN GRASS Aristida longiseta Steud. Perennial; in large tufts; culms 20 — 50 cm. tall; panicles narrow, standing well above the leaves, appearing as a feathery mass of long, reddish awns. The awns may reach lengths of 6 — 8 cm. The narrow, stiff, straight leaves may be mostly at the base of the plant. Dogtown grass is an inferior forage spe- cies. The sharp awns and pointed cal- lus cause the florets to pierce the facial tissues of grazing animals, causing seri- ous infections and sometimes blindness. Dry plains and foothills, especially on thin rocky soil or bare ground. July — October. Figure 200 Aristida fendleriana Steud. is similar in the panicle and spikelets, but most of the leaves are crowded in dense, curly basal tufts. Widespread in the Great Plains and western mountain states. 15a. Awn bent, twisted at least near the base, firmly attached to the lemma 18 107 HOW TO KNOW THE GRASSES 15b. Awn straight or bent, (rarely absent) readily separating from the lemma when mature; floret rather short and plump 16 16a. Lemmas covered with short, appressed hairs or glabrous 17 16b. Lemmas covered with long, silky white hairs; panicle open, with spreading branches. Fig. 201. INDIAN RICEGRASS Oryzopsis hymenoides (R. & S.) Ricker Perennial; culms 30 — 60 cm. tall, in dense, tough tufts. The panicles are very open, with scattered spikelets on the tips of slender, zig- zag pedicels. The lemmas are brownish-black, but are covered with a dense cloud of white hairs. The awns readily break away from the lemmas, and may be missing from many of the spikelets. This is one of the most valu- able forage grasses in the desert areas of the West. It is especially prized for winter feed. The large seeds are nutritious feed for live- stock and formerly were used as food by the Zuni Indians. April — August. Figure 201 17a. Spikelets (without the awns) 6 — 9 mm. long; leaf blades flat, all at the base of the plant. Fig. 202. Oryitopsis asperifolia Michx. Perennial; tufted, with numerous long flat basal leaves; culms 20 — 70 cm. long, usually spreading, lacking leaf blades (sheaths pres- ent). The hard cylindrical lemmas are yel- lowish in color. Scattered in sandy or rocky woods. May — June. Oryzopsis racemosa (Smith) Ricker is simi- lar in general habit, but has long upper culm leaves and short basal leaves. The lemmas are black. Quebec to Delaware, westward to Kentucky and South Dakota. Jime— Augxist. Figure 202 108 HOW TO KNOW THE GRASSES 17b. Spikelets (without the awn) less than 3 mm. long; leaves thread- like; some leaf blades on the culms. Fig. 203. Oryzopsis micrantha (Trin. & Rupr.) Thurb. Perennial; in dense tufts; culms thin, 30 — 70 cm. tall; leaf blades flat or rolled, less than 2 mm. wide, scabrous; panicles 10 — 15 cm. long, with slender spreading branches, the spikelets borne near the tips; glumes thin and translucent; lemmas smooth or with oppressed hairs, yellow or brownish; awns readily de- tachable, straight, 5 — 10 mm. long. Open woods and dry rocky slopes, intermediate ele- vations. The plants are said to have some forage value. June — July. Oryzopsis miliacea (L.) Benth. (SMILO GRASS) has similar spikelets but broad, flat leaf blades, 8 — 10 mm. wide. It is cultivated for forage in California. Introduced from Europe Figure 203 18a. Lemma 5 — 12 mm. long, excluding the awn 19 18b. Lemma 15 — 25 mm. long. Fig. 204. PORCUPINE GRASS Stipa spariea Trin. Perennial; culms in small hard tufts, about 1 m. tall. The panicle is erect or nodding, with few spikelets; glumes whitish; mature lemmas brown; awns 15 — 20 cm. long, with one or two sharp bends. The floret of Stipa species is a remarkable self-planting device. When it falls from the glumes, its sharp pointed callus readily penetrates the ground. The backward-pointing hairs prevent the flor- et from pulling out. The twisted portion of the awn coils and uncoils as the moisture content of the air changes, causing the bent arm of the awn to revolve slowly until it comes in contact with grass stems or other objects. Then the whole lemma is hterally screwed down into the earth. Unfortimately the same process will occur if the florets get into wool or hair of ani- mals, and these florets can thus cause serious puncture wounds on grazing animals, especially around the eyes, nose, and mouth. Prairies and dry open groimd, mostly in the Midwest. June — July. Figure 204 109 HOW TO KNOW THE GRASSES 19a. Lemma 8 — 12 mm. long; glumes 12 — 20 mm. long 20 19b. Lemma 5 — 6 mm. long; glumes 5 — 10 mm. long 22 20a. Lemma without a smooth whitish summit 21 20b. Lemma with a smooth whitish ring at the summit. Fig. 205. TEXAS NEEDLEGRASS Stipa leucotricha Trin. & Rupr. Perennial; culms 30 — 60 cm. tall; leaf blades 10 — 30 cm. long, very narrow, rolled, rough to the touch, dark green. The awn is 6 — 10 cm. long, with two bends. The lower sheaths contain very peculiar hidden spike- lets (cleistogamous), lacking glumes and with a very short-awned lemma. This species be- gins growth very early, in late winter and early spring and is prized for winter feed. The owned florets may injure sheep. Dry plains. May — June. 6 -i- I 10 Figure 205 21a. Mature lemma chocolate brown or black 22 21b. Mature lemma pale or brownish. Fig. 206. NEEDLE AND THREAD Stipa comata Trin. & Rupr. Perennial; culms in tufts, 30 — 60 cm. tall. The panicle is a mass of curly awns, 10 — 15 cm. long. The base of the panicle is usually partially hidden in the uppermost sheath. Needle and thread is a valuable forage grass in many parts of the West. It is grazed especially in the spring and fall, before the "needles" are formed and after they fall. Prairies, plains, and dry open mountain slopes. June — August. Figure 206 110 HOW TO KNOW THE GRASSES 22a. Edges of lemma overlapping and hiding the palea; panicle elon- gated, spikelike, with many spikelets. Fig. 207. Stipa viridula Trin. Perennial; culms 60 — 100 cm. tall, in dense clumps; panicles slender, dense, elongated, 10^ — 20 cm. long. The glumes are glossy and rather translucent. Awn 2 — 3 cm. long, with two bends. Dry plains. This species yields good forage, June — August. Stipa robusta Scribn. (SLEEPY GRASS) is very similar, but taller (100 — 150 cm). It has a narcotic effect on horses who graze it. Dry plains, Colorado to Texas and Arizona. Figure 207 22b. Edges ol lemma not meeting, turned inward, with a deep groove between the edges; panicle with spreading branches/ bearing a few spikelets near their tips. Fig. 208. PINYON RICEGRASS Piptocbaetium iimbriatum (H. B. K.) Hitch. Perennial; culms in dense tufts, 40 — 80 cm. tall; leaf blades one-third to one-half as long as the culms, mostly at the base of the plant, thread-Hke and curved downward; panicles 5 — 15 cm. long; glumes about 5 mm. long, thin; floret dark-colored, glabrous or hairy; awns readily detachable, twice bent, 1 — 2 cm. long. Piiion ricegrass is said to be a valuable forage species. Open, rocky woods. The genus Piptochaetium is one of the old- est known grass genera. Fossils of the florets have been collected from Miocene rock for- mations in the western states. Figure 208 111 HOW TO KNOW THE GRASSES 23a. One or both glumes longer than the lemma (excluding the awn) 24 23b. Glumes shorter than or equal to the lemma in length 39 24a. Glumes both longer than the lemma, equal, strongly flattened and keeled, V-shaped in cross section 25 24b. Glumes either imequal or not strongly keeled, never with long fringing hairs on the keel 26 25a. Spikelets about 5 mm. long; glumes cut square at the tip, the mid- nerve protruding as an awn; plants widespread, tufted. Fig. 209. TIMOTHY Phleuzn pratense L, Perennial; tufted, the culms 50 — 100 cm. tall, often with swollen, bulb-like bases. The dense, cylindrical panicles are stiff and somewhat bristly. Timothy is one of the important hay meadow grasses in the northern states, and is very widely estab- lished in the wild as well, in the moister portions of the country. June — July. i - Figure 209 Phleum alpinum L. (ALPINE TIMOTHY), with short, plump, dark colored panicles, occurs in wet mountain meadows at high altitudes in the West and from Greenland to Alaska. 25b. Spikelets 10 — 20 mm. long; coarse, stiff grasses of sand beaches; rhizomes long and stiff. Fig. 210. AMERICAN BEACHGRASS Ammophila breviligulata Fernald Perennial; spreading by very long, stiff rhizomes. The plants are coarse and tough. Panicles dense and cylindrical, 10 — 20 cm. long. The plants are highly important sand binders ' on dunes along the Atlantic Coast and on sand beaches of the Great Lakes. July — September. Figure 210 26a. Glumes not swollen near the base. 27 112 HOW TO KNOW THE GRASSES 26b. Glumes swollen near the base. Fig. 211. NIT GRASS Gastridium ventricosum (Gouan) S. & T. Annual; tufted, shallow-rooted; culms 20 — 55 cm. tall; panicles dense, cigar-shaped, with glossy silvery or yellowish spikelets. The min- ute floret is concealed by the glumes. Weed of fields and waste places, common on the Pacific Coast. Introduced from Europe. May —July. Figure 21 1 27a. Rachilla prolonged as a short hairy bristle be- hind the palea (CARE). Fig. 212 28 27b. Rachilla not prolonged behind the palea. Figure 212 30 28a. Awn straight, hidden within the glumes; hairs nearly as long as the lemma 29 28b. Awn bent sidewise, protruding from the glumes; hairs shorter than the lemma. Fig. 213. PINEGRASS Calamagrostis rubescens Buckl. Perennial; culms in tufts, 60—100 cm. tall; plants producing rhizomes; leaf blades scabrous, 2 — 4 mm. wide, flat or somewhat rolled; panicles dense and cylindrical, 7 — 15 cm. long, pale or pur- pUsh in color; glumes 4 — 5 mm. long; sterile rachilla joint about 1 mm. long, its hairs about twice as long. While common, pinegrass is lov.^ in palatabili- ty, especially for sheep, and is Httle grazed except when young and green. The plants make a strong, tough turf which resists heavy grazing and tram- pling. Most of the reproduction is by rhizomes. Coniferous forests, up to 3300 m. elevation. June — August. Figure 21 3 113 HOW TO KNOW THE GRASSES 29a. Panicle open, pyramidal, with spreading or drooping elongated branches. Fig. 214. BLUEJOINT Calamagrostis canadensis (Michx.) Beauv. Perennial; culms slender, in small tufts, 60 — 150 cm. tall; plants producing many, long, creeping rhizomes. The panicles vary from rather dense to loose, pyramidal, and nod- ding. Bluejoint is a very widespread and common species found in marshes and wet ground. While rather tough, it furnishes a good deal of forage and is sometimes cut for marsh hay in the North Central States. June — August. Figure 214 29b. Panicle dense, cylindrical, with short, erect branches. Fig. 215. Calamagrostis inexpansa Gray Perennial; culms in tufts, 40—120 cm. tall- plants producing rhizomes. The dense, cylin- drical panicle may be pale or purplish. The leaf blades are rough to the touch and usually rolled; hgules 4 — 7 mm. long. Marshes and wet meadows, apparently sometimes on dry soil in the western mountains. June — July. Figure 215 30a. Glumes unequal, the first shorter than the floret, the second longer w 1 30b. Glumes equal, both longer than the floret; palea shorter than the lemma; tufted or rhizome-bearing plants 32 31a. Lemma without long hairs on the callus; glabrous or with ap- pressed hairs on the back *^ 114 HOW TO KNOW THE GRASSES 31b. Lemma bearing a copious tuft of white hairs attached to the cal- lus; tall perennial with stout rhizomes. Fig. 216. SAND REEDGRASS Calamovilia longiiolia (Hook.) Scribn. Figure 216 Perennial; culms 50 — 180 cm. tall, in small tufts; plants producing long, tough, scaly rhizomes; panicles large, 15 — 35 cm. long; lemmas bearing copious tufts of straight white hairs on the callus. The plants are coarse and tough, but make considerable amounts of winter feed and are sometimes cut for hay. Sandy soil, hills and plains; shores of Lake Huron and Lake Michigan. August — September. Calamovilia gigantea (Nutt.) Scribn. & Men. is similar but larger, and has hairs on the backs of the lemmas. Sand dunes of the great plains and southwestern states. 32a. Glumes with long awn-tips, or the lemmas long-awned from the tip; panicles dense; rhizomes densely covered with overlapping scales 42 32b. Glumes not awned; lemmas awnless or owned from the back; pani- cles open or dense; rhizomes, if present, not covered with over- lapping scales 33 33a. Palea at least half as long as the lemma; plants often with rhi- zomes or stolons 34 33b. Palea absent or less than Va, as long as the lemma; plants tufted, lacking rhizomes or stolons 36 34a. Plants with erect stems; panicles open, pyramidal, 35 115 HOW TO KNOW THE GRASSES 34b. Plants with creeping stolons, rooting at the nodes and forming flat mats; rhizomes absent; panicle narrow, the branches closing up after the flowering period. Fig. 217. CREEPING BENT Agrostis palustris Huds. Perennial; low, spreading by numerous fine leafy stolons. This species is much used for golf greens and tine lawns, but requires frequent cutting and watering to produce a good turf, and the plants are subject to several serious diseases. New lawns are usually produced by planting pieces of chopped turf, which take root and spread to form a continuous sod. Repro- duction by seed is also possible, but seed of many strains is very scarce or unob- tainable. Various forms of this species are known as seaside bent, Coos Boy bent, Washington bent, and MetropoHtan bent. Marshes, especially along seacoasts, wet ground around streams, springs, lakes, and ditches. Also known from Europe and Asia. June — September. Figure 217 35a. Ligules 1 — 2 mm. long; leaf blades 1 — 3 mm. wide. Fig. 218. BROWNTOP Agrostis tenuis Sibth. Perennial; plants 20 — 40 cm. tall; rhizomes absent but short stolons sometimes present; leaf blades very narrow; Hgules on sterile shoots about 1 mm. long, on the culms up to 2 mm. long; panicles usually 5 — 10 cm. long, brownish, open and delicate, the spike- lets all near the outer tips of the branches. Agrostis tenuis is cultivated as a lawn and pasture grass and is sometimes referred to as Rhode Island bent. Prince Edward Island bent, Colonial bent. New Zealand bent, or Astoria bent. The plants are occasionally found growing wild in regions where brown- top is cultivated. Some forms possess lem- mas which bear a delicate awn attached near the base. Introduced from Europe. June —July. Figure 218 116 HOW TO KNOW THE GRASSES 35b. Ligxxles 3 — 7 mm. long; leai blades 2 — 6 mm. wide. Fig. 219. REDTOP Agrostis alba L. Perennial; culms up to 1 — 1.5 m. tall; nu- merous creeping rhizomes present; panicle pyramidal, with rather dense whorls of branches, flowering to their bases. Redtop is one of our most important meadow grasses, and is also used in lawn seed mixtures. Roadsides, meadows, waste ground; very widely naturalized. June — August. Intro- duced from Europe. Figure 219 36a. Panicle narrow, with the short branches bearing spikelets nearly to their bases 37 36b. Panicle open, the spreading branches bearing spikelets at their outer ends only 38 37a. Slender alpine plants; leaf blades 5 cm. long or shorter, 1 — 2 mm. wide; ligules 1 — 2 mm. long; panicles usually less than 5 mm. wide. Fig. 220. Agrostis vanabilis Rydb. i. - Figure 220 Perennial; tufted; culms 10 — 20 cm. tall; panicles small, 2 — 6 cm. long; spikelets about 2.5 mm. long; lemmas about 1.5 mm. long; palea very short. High altitudes in the moim- tains, usually above timberline along creeks and on slopes. Forage value good. July — August. Agrostis humilis Vasey. Similar but smaller, differing from the above chiefly in having a palea about 2/3 as long as the lemma; plants 5 — 15 cm. tall; panicles purple, slender, 1 — 3 cm. long. Excellent forage. Bogs and moun- tain meadows above timberline, Montana and Washington to Colorado and Nevada. July — August. 117 HOW TO KNOW THE GRASSES 37b. Stouter plants of medium and low altitudes; longer leaf blades 8 — 10 cm. long; ligules 3 — 6 mm. long; panicles usually 1 — several cm. wide. Fig. 221. SPIKE REDTOP Agrostis exarata Trin. Perennial; tufted; culms 20 — 120 cm. tall- panicles spikelike, either thin or thicker and somewhat lobed. Lemma sometimes owned. This is one of the most important western range grasses. It is palatable to both domes- tic livestock and wild grazing animals. Usu- ally on moist ground, in meadows, along streams, and in open woodlands. July — August. Figure 221 38a. Panicles with long, slender main branches which branch again only on the outer half. Fig. 222. TICKLEGRASS Agrostis scabra WUld. bSsi* wim Figure 222 Perennial; culms slender, 20 — 80 cm. tall; leaf blades threadlike, in dense tufts at the base of the culms; panicles delicate, readily breaking away from the plants and blown by the wind as tumbleweeds. Forage value fair. Tickle- grass is a very widespread species, on open ground or in partial shade, espe- cially on moist soil. June — September. Agrostis kyemalis (Walt.) B. S. P. is similar but has spikelets bunched at the tips of the branches. It blooms earlier, in May and early June. At- lantic coastal plain and lower Mississip- pi Valley. 118 HOW TO KNOW THE GRASSES 38b. Main panicle branches branching again below the middle. Fig. 223. Agrostis perennans (Walt.) Tuck. Perennial; tufted; culms 20 — 80 cm. tall; panicles usually delicate and lace-like, especially in shade-grown plants. Lem- mas rarely awned. Dry open fields and woodlands. July — October. Agrostis oregonensis Vasey is similar, but larger and more vigorous. Marshes; Montana to British Columbia, southward to Wyoming and California. Figure 223 39a. Glumes minute, less than 1/5 as long as the lemma 40 to - 39b. Glumes hall as long as the lemma or longer 41 40a. Rachilla extending beyond the palea of the floret as a bristle; erect, broad-leaved forest grass. Fig. 224. BTacbyelytTum eiectum fSchreb.) Beauv. Perennial; tufted; culms 60 — 100 cm. tall; leaf blades 10 — 15 mm. wide, flat, rather light green; leaf sheaths and blades usually hairy; panicles slender, 5 — 15 cm. long, with erect branches; first glume nearly absent; second glume up to 2 mm. long; floret cylindrical, firm, about 1 cm. long, with an awn 1 — 2 cm. long. Typical B. erectum is found mostly south of the glaciated areas of the eastern United States. The lemmas have stout, stiff hairs along the nerves and are otherwise glabrous. It grows in scattered stands in upland woods. June — July. Var. septentrionale Babel grows mostly north of the glacial boundary, or southward in the mountains. The lemmas are sparsely and uni- formly covered with minute appressed hairs or are nearly glabrous. Moist thickets and swampy woods. Also known from Japan. Figure 224 119 HOW TO KNOW THE GRASSES 40b. Rachilla not prolonged; weak, sprawling weedy grass of disturbed soil, lawns, etc. Fig, 225. NIMBLE WILL MuWenbergia schreberi GmeL Perennial. The culms in early season are quite erect, but by flowering time they become much-branched and sprawl on the ground, the lower nodes often rooting. The erect portions of the culms are 10 — 30 cm. long. Leaf blades usually 2 — 4 mm. wide; foHage glabrous; panicles borne at the tips of the culms and from leaf axils, slender and weak, 5 — 15 cm. long. The glumes are vanishingly small, the first sometimes entirely lacking and the second only a few tenths of a miUimeter long. Florets cylin- drical, about 2 mm. long, hairy on the callus; awn 2 — 5 mm. long, very slender. Nimble Will may become a weed in shaded lawns and shrubbery borders, but it does not seem very aggressive. It also is found growing in woods and thickets, roadsides and city streets, old fields, and meadows. August — October, rarely blooming in June or July. Figure 225 41a. Lemma bearing an awn; nerves of lemma 3 or 5 42 41b. Lemma awnless; nerves 1. 3, or 5 51 42a. Plants producing elongated rhizomes 43 42b. Plants lacking rhizomes (old tufts sometimes stooling out) 47 43a. Panicles slender, with short ascending branches; spikelets owned or awnless, on short pedicels 44 120 HOW TO KNOW THE GRASSES 43b. Panicles open, with spreading branches; tiny awnless spikelets on long slender pedicels. Fig. 226. SCRATCHGRASS MuhJenbergia asperifoha (N. & M.) ParodL Perennial; bushy. 10 — 50 cm. tall, with rhizomes; panicles open, dome-like, 5 — 15 cm. long; plants pale green in color; leaf blades 2 — 5 cm. long, 1 — 2 mm. wide; H- gules minute. The grains are often swol- len up into spherical shape by the action of a fungus. Moist, often alkahne soil. June — September. Muhlenbergia arenacea Buckl. is similar but has prominent ligules, 1 — 2 mm. long. Texas to Colorado and Mexico. Figure 226 44a. Leaf blades 3 mm. wide or wider, more than 5 cm. long, flat; lem- mas awned or awnless 45 44b. Leaf blades 1 — 2 mm. wide, less than 5 cm. long, usually rolled; lemmas awnless. Fig. 227. MAT MUHLY Muhlenbergia richaTdsonis (Trin.) Rydb. Perennial; much-branched, spreading by hard, thin rhizomes and forming mats, the erect portions of the culms 5 — 60 cm. long; panicle slender, 2 — 10 cm. long. Mat muhly is a grass of open, often wet or alkaline soil. While rather tough, it furnishes fairly good Hvestock feed. The densely matted plants furnish considerable erosion protection to the soil. July — September. Also known as M. squGTTOsa (Trin.) Rydb. Figure 227 45a. Glumes not longer than the lemma, less than 3.5 mm. long .... 46 121 HOW TO KNOW THE GRASSES 45b. Glumes much longer than the lemma, tapering to awn tips. Fig. 228. Muhlenbergia glomerata (Willd.) Trin. Perennial; culms in tufts, 30 — 90 cm. tall, with slender creeping rhizomes; panicles dense, cylindrical, and somewhat lobed, often purplish in color, 3 — 10 cm. long; anthers 1 — 1.5 mm. long. Moist or rocky ground. July — October. Muhlenbergia lacemosa (Michx.) B.S.P. is similar, but has small anthers less than 1 mm. long. Prairies, wet or rocky ground, Manitoba and Indiana to Alberta and Washington. Figure 228 46a. Culms much-branched, with numerous small panicles in the axils of the leaf sheaths; stems smooth and shining. Fig. 229. Muhlenbergia irondosa (Poir.) Fern. Perennial; rhizomes present; culms becom- ing elongated, 40 — 100 cm. or more long, the plants becoming bushy and much-branched, frequently scrambling through bushes or other vegetation or sprawling; panicles at the tips of the culms and protruding from nearly every leaf sheath, up to 10 cm. long, rather dense; leaf blades flat, scabrous, 3 — 7 mm. wide; glumes 2 — 4 mm. long, tapering gradually from base to an owned tip; lemmas 2 — 3 mm. long, awnless or owned. This is a very common species in thickets and woods and on roadsides and stream banks. August — October. Muhlenbergia sobolifera (Muhl.) Trin. is somewhat similar, but the glumes curve abruptly to awn tips from a point above the middle. The culms are erect and sparingly branched. Lemmas awnless. Dry woods. New Hampshire to Virginia, westward to Nebraska and Texas. July — October. Figure 229 122 HOW TO KNOW THE GRASSES 46b. Culms not much branched; panicles all at the tips of long pro- truding branches or the main culms; stems dull, roughened with minute hairs, especially below the joints. Fig. 230. Muhienbergfa sylvatica Torr. Perennial; culms 40 — 100 cm. tall; rhi- zomes present; plants often bushy; leaf blades flat, soft, 2 — 8 mm. wide; panicles narrow, arching, with thin, erect branches; some of the spikelets on pedicels as long as the glumes; glumes tapering to awn points, 2 — 3 mm. long; lemma sHghtly long- er, hairy on the callus and lower portion, with an awn 5 — 10 mm. long. The culms feel file-like when scratched with the finger nail, especially below the nodes. Forms with short awns or none are known. Woods, meadows, thickets, and roadsides. August — September. Muhienbergia mexicana (L.) Trin. is simi- lar but has denser, usually lobed panicles, most of the spikelets being nearly sessile on the branches; lemmas awnless; leaf blades 2 — 4 mm. wide. Rocky shores, moist woods, swamps. Through- out most of the United States except Texas and the southeastern states. 47a. Second glume not toothed 48 47b. Second glume 3-toothed near the tip. Fig. 231. Muhienbergia znontana (Nutt.) Hitch. Perennial; culms in large, dense tufts, 30 — 60 cm. tall; panicles slender, with as- cending branches. The 3-toothed second glume is the best identifying mark of this species. The old sheaths at the base of the plants become flat and stiff, Hke thin wooden splints. This species yields fairly palatable forage, especially when the herbage is young. Ponderosa pine, spruce, and fir forests. 2300—3300 m. elevation. July — October. Figure 230 Figure 231 123 HOW TO KNOW THE GRASSES 48a. Panicle very narrow, the short branches bearing spikelets nearly to their bases 49 48b. Panicle broad, open, the spikelets borne near the tips of the branches 50 49a. Awn shorter than the lemma or lacking. Fig. 232. Muhlenbergia cuspidata (Torr.) Rydb. Perennial; tufted; culms slender and wiry, 20 — 40 cm, tall; ligules minute; panicles very slender. Dry hills and prairies. July — Sep- tember. Muhlenbergia wrightii Vasey (SPIKE MUHLY) is similar but has a denser pani- cle, somewhat like timothy. The ligule is 1 — 2 mm. long. It is on important grazing grass on open or bushy ranges, ponderosa pine forests, from southern Colorado and Utah southward. Figure 232 49b. Awn 1 — several times as long as the lemma. Fig. 233. BULLGRASS Muhlenbergia emersleyi Vasey Perennial; in large tufts; culms tall and stout, 50 — 100 cm. tall; sheaths glabrous, flattened and keeled; lower leaf blades up to 50 cm. long; blades flat or folded, rough, 1 — 4 mm., wide; ligules thin, 1 — 2 cm. long; panicles long and narrow, 20 — 40 cm. long, with ascending, overlapping branches; spikelets often somewhat purplish; glumes scabrous; lemmas hairy on the lower half, awnless or with an awn up to 25 mm. long attached below the apex. Some panicles may have both owned and awnless spike- lets. Canyons and rocky woods; said to be a good soil binder. September — Oc- tober. Figure 233 124 HOW TO KNOW THE GRASSES 50a. Plants forming sprawling, much-branched bushes from knotty crowns. Fig. 234. BUSH MUHLY Muhlenbergia porteri Scribn. Perennial; the much-branched plants will form bushy growth a meter in diameter and height if ungrazed. Because of the very high palatability of this species for grazing live- stock, it is rarely seen except in the hearts of spiny bushes. The plants are semi-evergreen, the old culm bases producing new shoots in the succeeding year. Dry plains and deserts. July — September. Figure 234 50b. Stems erect, usually unbranched. Fig. 235. RINGGRASS Muhlenbergia torieyi (Kunth) Hitch. Perennial; plants forming circular or ring- shaped tufts, with numerous short, curly leaves, mostly clustered at the base of the plant. Ringgrass is a rather poor forage grass. Its presence usually indicates that better species have been killed out. Open plains, 1300—3300 m. elevation. July- August. Figure 235 51a. Floret bearing a tuft of hairs on the callus; pani- cles large and open. Fig. 236 . . genus CALAMO- VILFA. see Fig. 216. 51b. Floret without conspicuous hairs on the callus (sometimes hairy on the nerves) 52 125 HOW TO KNOW THE GRASSES 52a. Nerves of the lemma without silky hairs 53 52b. Lemma 3-nerved, the nerves densely covered with short silky hairs. Fig. 237. PINE DROPSEED Blepharoneuron iricholepis (Torr.) Nash Perennial; tufted; culms slender, almost leafless, 20—60 cm. tall. The leaf blades are crowded in a basal tuft about a third as long as the culms. The panicles are loosely cylindrical, somewhat grayish in color. This species is a good forage grass, especially in early season. Open parks and thin woods, ponderosa pine, spruce, and fir forests. July — October. Figure 237 53a. Lemmas with 3 — 5 nerves, awned or ownless; grain remaining inclosed by the lemma and palea; ovary wall not separable from the seed go back to 42 53b. Lemmas with one nerve, awnless; grain falling free of the lemma and palea at maturity; ovary wall when wet usually swelling into a jelly-like material which can be peeled from the seed. . .54 54a. Glumes plainly unequal in length 55 54b. Glumes equal in length, nearly as long as the floret; plants an- nual, in small tufts with very shallow roots. Fig. 238. Sporoboius vaginae/iorus (Torr.) Wood Annual; culms thin, wiry, 10 — 40 cm. tall, in small tufts; panicles mostly concealed within the up- per leaf sheaths, or only the tips protruding. The lemmas are usu- ally blackish-spotted, and the pa- lea is often longer than the lem- ma. Both lemma and palea are covered sparsely with appressed hairs. Dry sterile open ground. August — October. ^,o Sporoboius neglectus Nash is Figure 238 , , i i similgr, but has shorter, plumper spikelets with glabrous lemmas. Northeastern and midwestern United States. 126 HOW TO KNOW THE GRASSES 55a. Spikelets 4 — 7 mm. long. 56 55b. Spikelets 1 — 2.5 mm. long 57 56a. Panicle open, with spreading branches. Fig. 239. PRAIRIE DROPSEED Sporobolus heterolepis Gray Perennial; plants forming large tufts; culms 30 — 70 cm. tall; panicles narrowly ovoid. The spikelets become much dis- tended by the ripening grain, which is spherical and yellowish at maturity and about 2 mm. in diameter. The pclea readily splits down the middle as the grain develops. Prairies. July — October. Figure 239 56b. Panicle spikelike, mostly hidden in the uppermost sheath. Fig. 240. Sporobolus asper (Michx.) Kunth Perennial; tufted; culms 60 — 120 cm. tall; leaf blades flat or rolled, 1 — 4 mm. wide, tapering to a slender tip; panicles whitish or somewhat purplish in color, 5 — 15 cm. long. Open ground and prairies. August — September. Sporoboius macer (Trin.) Hitch, is very similar, but has scaly rhizomes. Pine forests; Mississippi to Oklahoma and eastern Texas. Sporoboius clandestinus (Biehler) Hitch, is similar, but has hairy florets; lemma and palea slender-pointed, the palea longer than the lemma. Dry sandy lands; Connecticut to Figure 240 Wisconsin, Kansas, Texas and Florida. 57a. Sheaths glabrous or nearly so at the summit. 58 127 HOW TO KNOW THE GRASSES 57b. Sheaths bearing conspicuous tufts of white hairs at their summits. Fig. 241. SAND DROPSEED Sporoboius CTyptandrus (Torr.) Gray Perennial; tufted, the erect or spreading culms 30 — 100 cm. long; panicles borne at the apex of the culms and in the axils of the upper sheaths. The tufts of straight silky hairs on the flanges at the summits of the sheaths are prominent. Sand drop- seed is a rather important forage species on coarse or sandy soil in the West. It produces an abundance of fine, long-lived seed, and will recover rapidly from the effects of overgrazing. July — October. SpoTobolus giganteus Nash (GIANT DROPSEED) resembles the above, but may be distinguished by its large size, from 1 — 2 m. tall, and slightly larger spikelets, 2.5 — 3 mm. long. Sand plains, western Oklahoma and Texas to Colorado and Arizona. Figure 241 58a. Panicle not more than twice as long as wide; leaf blades usually rolled. Fig. 242. ALKALI SACATON Sporoboius airoides Torr. Perennial; culms tough and rigid, in large clumps; plants 50 — 100 cm. tall. The large, open, dome-shaped panicles make up half or more of the height of the plant. The paleas of the florets often spHt as the grain develops. The plants can grow on very salty or alkaUne soil. Although the herbage is tough, it is taken greedily by livestock, probably because of the large amount of salt in the tissues. Frequently, minute salt crystals can be seen glisten- ing on the leaf surfaces with a hand lens. Plains and alkaH flats, often on heavy clay soils. Jime — September. Figure 242 128 HOW TO KNOW THE GRASSES 58b. Panicle three or more times longer than wide; leaf blades usually flat. Fig. 243. SACATON Sporobolus wrightii Munro Perennial; culms in large tufts, stout and tough, 1 — 2.5 m. tall; panicles up to 60 cm. long, the branches bearing spike- lets nearly to their bases. The plants furnish good grazing when young, and are sometimes cut for hay. River flats, especially where overflows occur. July — September. Figure 243 TRIBE VI. ZOYSIEAE la. Spikelets inclosed in spiny burs, the spines hooked at the tips. Fig. 244. COCKLEBUR GRASS Tragus berteTonianus Schult. Annual; culms 10 — 40 cm. long, spreading. The burs are borne along a slender raceme, from which they fall readily. Each bur con- sists of a group of 2 — 5 spikelets, but the sec- ond glumes of the two lower spikelets are covered with hooked prickles and conceal the remainder. The plants occur on dry open ground in the Southwest and also at scattered points on the east coast where wool is pro- cessed. The burs are readily transported by the wool of sheep. Probably introduced from the old world; extending through the warmer portions of both hemispheres. August — Oc- tober. Figure 244 lb. Spikelets not inclosed in spiny burs 2 2a. Spikelets falling in groups of 3, all without stalks 3 2b. Spikelets falling in pairs, each spikelet on a short stalk genus Lycurus. Fig. 191. 129 Figure 245 HOW TO KNOW THE GRASSES 3a. Plants spreading by slender creeping stolons; culms 10 — 30 cm. tall. Fig. 245. CURLY MESQUITE GRASS. Hilaria belangeri (Steud.) Nash Perennial; forming extensive flat mats, the stolons rooting at the nodes. Dry plains, foothills, and brushy land, 650 — 1800 m. elevation; often on heavy clay soils. Blooming occurs sporadically dur- in the growing season. Curly mesquite is an important range grass in the Southwest. Because of its stolons, it stands up well under heavy grazing. Where it occurs with buffalo grass, it is regarded as inferior to buf- falo, being less productive and not cur- ing out as well. The plants greatly re- semble those of buffalo grass {Buchloe dactyloides, see Fig. 247), but may be distinguished by the spikelets and by the following features: 1. Color. Curly mesquite is light green when fresh, whitish when dry. Buffalo grass is grayish or olive green when fresh; tan, brownish or purplish when dry. 2. Stolons. The stolons of curly mesquite are round in cross sec- tion, very slender, and have tufts of hair at the joints. Those of buffalo grass are oval in cross section, stouter, and smooth at the joints. 3b. Plants erect, without stolons; rhizomes present. Fig. 246. GALLETA GRASS Hilaria jamesii (Torr.) Benth. Perennial; culms tough, erect, 30 — 50 cm. tall, from stout, scaly rhizomes. The racemes of clustered spikelets are whit- ish. After the groups of spikelets fall, the rachis remains behind as a thin, zig- zag straw. Galleta (pronounced gie- yetta) is an important forage grass on dry plains and deserts in the Southwest. It is fairly palatable to horses and cattle when fresh and green, but is scarcely eaten when dry. June — August. Hilaria mutica Benth. (TOBOSA GRASS) is very similar, but the first glume on each lateral spikelet is fan- shaped. Heavy clay soils, especially on river bottoms where flooding occurs. Western Texas to Arizona. Hilaria rigida (Thurb.) Benth. (BIG GALLETA) is larger, and has the culms covered with a dense white felt of hairs. Southwestern deserts. Figure 246 130 HOW TO KNOW THE GRASSES TRIBE VII. CHLORIDEAE la. Spikelets not inclosed in beads; flowers perfect 2 lb. Pistillate spikelets inclosed in yellowish, bony, bead-like structures; plants unisexual; staminate spikelets borne in 1 — 3 spikes; plants producing extensive creeping stolons. Fig. 247. BUFFALO GRASS Buchloe dactyloides Engelm. Perennial; spreading widely by stolons; pistillate spikelets inclosed in bead-like bodies with a short green crown on top; staminate spikelets in short, flag-like spikes. The two sexes are borne on separate plants. The diminutive plants are rarely more than 20 cm. tall. Leaves short, curly, grayish-green. Despite its small size, this species is one of the most important forage grasses of the Great Plains, furnishing excellent forage year long. It resembles closely Hilaria belangeri (see Fig. 245). For ways of distinguishing the two when not fruiting, see the discussion under that species. Buffalo grass frequently grows with blue grama grass (see Bouteloua gracilis. Fig. 271) and resembles it, except that the grama grass lacks stolons. Blooming time mostly in the spring, but also later in the season. 2a. Inflorescences consisting of a few spikelets hidden in the sheaths of stiff, sharp-pointed leaves; annual, making circular or dome- shaped patches from one root. Fig. 248. FALSE BUFFALO GRASS Munroa squarrosa (Nutt.) Torr. Figure 247 Leaves of Munroa are stiff, harsh, and some- what curled backwards. The spikelets are borne in two's or three's on short, one-sided spikes. The small vegetative leaves and glumes are similar and hard to distinguish. The plants grow on overgrazed or disturbed soil in blow-outs, around prairie dog towns, corrals, etc. Forage value very low. June — August. Figure 248 131 HOW TO KNOW THE GRASSES 2b. Inflorescence not hidden by the leaves; plants annual or perennial, of various habits 3 3a. Spikelets with 2 or more fertile florets 4 3b. Spikelets with 1 fertile floret, often variously shaped rudimentary ones above the perfect one 8 4a. Spikes numerous, in a panicle 5 4b. Spikes few (usually less than 6), all arising from one central point 7 5a. Spikelets 5 — 10 mm. long; lemmas awned or awnless 6 5b. Spikelets 1 — 2 mm. long; lemmas awnless. Fig. 249. RED SPRANGLETOP LepfochJoa iiliioTznis (Lam.) Beauv. Annual; plants tufted, 20 — 70 cm. tall. The reddish or purple panicles may be half the height of the plants, with numer- ous thread-like spikes bearing the very tiny spikelets. Red sprangletop is a rather rampant weed, frequent on bottomlands, in fields, and in gardens. August — Sep- tember. Figure 249 132 HOW TO KNOW THE GRASSES 6a. Lemmas notched at the blunt apex, awnless, glabrous or nearly so. Fig. 250. GREEN SPRANGLETOP Leptochloa dubia (H. B. K.) Nees Perennial; tufted; culms 50 — 100 cm. long, tough, erect; leaf sheaths smooth; blades flat or somewhat rolled or folded, up to 10 mm. wide; panicles up to 15 cm. long, the spreading spikes 3 — 12 cm. long; spikelets 5 — 10 mm. long, usu- ally with 5 — 8 or occasionally fewer florets; lemmas oblong, blunt, the tip notched, the midnerve sometimes pro- truding. The plants sometimes bear cleistogamous inflorescences hidden in the sheaths. This species has some value as a forage grass in the South- west. Sandy or rocky open ground. March — September. Figure 250 6b. Lemmas tapering to a sharp point, awned, hairy on the nerves. Fig. 251. Leptochloa fascicularis (Lam.) Gray Annual; tufted; culms 30 — 100 cm. long, erect or horizontally spreading; plants be- coming much-branched; leaf blades flat or somewhat rolled; panicles rather stiff, usually partly hidden in the leaf sheaths, 10 — 20 cm. long, the individual spikes up to 10 cm. long; spikelets 7 — 12 mm. long, with 6 — 12 florets; awns ranging from very short to 4 — 5 mm. long. Moist or alkahne soil, salt marshes, open ground. July — September. This is an unusually widely- ranging grass, extending southward through the American tropics to Argen- tina. It is sometimes placed in the genus Diplachne. Figure 251 133 HOW TO KNOW THE GRASSES 7a. Rachis of each spike extending beyond the spikelets as a naked point; second glume owned. Fig. 252. Dactylocteniuzn aegyptium (L.) Richt. Annual; tufted; culms upright or spread- ing out and forming mats, rooting at the lower nodes. The seeds (ovary wall is lost) are brownish, about the size of a pinhead, and oddly sculptured. Weed on cultivated ground. This species was apparently once planted by the Indians along the lower Colorado River for grain. Introduced from Europe. Sum- mer, or almost yearlong in the far South. Figure 252 7b. Rachis of the spikes not extended beyond the spikelets; glumes without awns. Fig. 253. GOOSEGRASS Eleusine indica (L.) Gaertn. Annual; culms up to 50 cm. long, spreading horizontally or standing erect; plants often making flat mats. Goosegrass is a very com- mon weed of fields, gardens, paths, and dis- turbed ground generally in the southeastern United States. Introduced from the warmer sections of the world. March — October. Figure 253 8a. Spikelets with a single floret, without sterile or rudimentary ones above it 9 8b. Spikelets with 1 or more modified sterile florets above the perfect one 14 134 HOW TO KNOW THE GRASSES 9a. Plants lacking stolons; rachilla not prolonged beyond the floret. . 10 9b. Plants producing extensive creeping stolons; rachilla prolonged beyond the floret as a smooth bristle. Fig. 254. BERMUDA GRASS Cynodon dactylon (L.) Pers. Perennial; producing both stolons and rhizomes and forming a fine green turf; erect portions of culms 10 — 40 cm. tall, bearing about 4 — 5 slender spikes at the apex. Bermuda grass is one of the prin- cipal lawn grasses in the South and furn- ishes much pasturage as well. It is very persistent when once established and may become a serious weed pest on agricultural lands. This species is apparently native to the tropics of the Old World, but has become widely dispersed in warmer parts of the world. Blooming period extends through the warm season, and may be yearlong in the subtropics. Figure 254 10a. Spikelets several times longer than wide, ovate in outline 11 10b. Spikelets nearly circular in outline, falling entire. Fig. 255. SLOUGH GRASS Beckmannia syzigachne (Steud.) Fern. Aimual; tufted; plants up to 100 cm. tall. The slender, wand-Uke panicles of spikes produce large quantities of wrinkled, cir- cular spikelets which shatter from the plants at a touch. Plants rather tender and succulent; forage value good. Wet mead- ows; shores of ditches and lakes, mostly in the western states. The plants are some- times cut for hay. July — August. Figure 255 135 HOW TO KNOW THE GRASSES 11a. Plants with rhizomes; spikelets disarticulating below the glumes, falling whole 12 lib. Plants tufted, lacking rhizomes; spikelets disarticulating above the glumes, the floret dropping. Fig. 256. TUMBLEGRASS Schedonnardus paniculatus (Nutt.) Trel. Perennial; tufted; plants 20 — 40 cm. tall, with short, crowded basal leaves. Most of the height of the plant is made up of the skeleton-like panicle of very slender spikes. The main axis of the inflorescence is some- what spiral. The whole panicle breaks from the plant when ripe and rolls with the wind, thereby distributing the seed. This is a grass of poor, dry soil, especially on overgrazed or disturbed areas. Forage value very low. June — August. Figure 256 12a. Leaf blades flat when fresh, 4 — 25 mm. wide 13 12b. Leaf blades rolled, 2 mm. or less wide. Fig. 257. SALT-MARSH GRASS Spartina patens (Ait.) Muhl. 13 Figure 257 Perennial; spreading by slender, scaly rhizomes, forming large colonies in coastal salt marshes along the Atlantic and Gulf coasts. Culms up to 1 m. tall, usually shorter. This grass is tough and harsh, but is frequently harvested for hay, which is used as packing material. The plants are valuable as land-builders along the coast, trapping and holding the tidal mud. July — September. Spartina gracilis Trin. (ALXALI CORD- GRASS) is similar, but is found on alkaU or sahy flats in the interior of the United States, from the Dakotas to Kansas, west- ward to Washington and CaUfomia. 136 HOW TO KNOW THE GRASSES 13a. Leaf margins rough to the touch; plants widespread. Fig. 258. SLOUGH GRASS Spartina pectinata Link Perennial; spreading by tough, scaly rhizomes which are up to 1 cm. thick; culms tall, 1 — 2 m. in height. The whole plant is coarse and tough, with saw- edged leaves. Slough grass was former- ly one of the dominant grasses of the tall grass prairie region of the north cen- tral United States. Now it survives largely along roadsides, in ditches, and on wet ground. July — September. /^ Spartina cy^°^^^^^^^^ ^^-^ Roth is taller, has numerous spikes; second glume without an awn. Salt marshes, Atlantic and Gulf coasts. Figure 258 13b. Leaf margins smooth; plants of Atlantic coastal salt-marshes. Fig. 259. Spartina alterniflora Loisel Perennial; spreading by rhizomes; culms .5 — 2.5 m. tall, thick and spongy; leaf blades flat, 5 — 15 mm. wide, tapering to a fine point; panicles narrow, the spikes slender and erect, 5 — 15 cm. long; spikelets about 1 cm. long, the floret smooth or sHghtly hairy. Coastal salt marshes, often growing in shal- low water. Introduced along the coast of southwestern Washington. July — October. Nearly a century ago, this species was in- troduced into southern England. There it formed a highly successful natural hybrid with a European species. This hybrid, Spar- tina townsendii, is now building extensive areas of dry land from former tidal mud flats there. /o Figure 259 14a. Second glume without a protruding bristle on the back; inflores- cence of 1 — many spikes 15 137 HOW TO KNOW THE GRASSES 14b. Second glume bearing a protruding bristle on the middle of the keel; inflorescence a single curved spike. Fig. 260. TOOTHACHE GRASS Ctenium aromaticum (Walt.) Wood Perennial; tufted; plants 1 — 1.5 m. tall. The bases of the plants are surrounded by the coarse, fibrous remains of the old sheaths. Toothache grass is a plant of wet pine woods on the sandy coastal plain. The fresh roots are said to have a spicy smell. The plants furnish some forage for cattle in the South. May — July. Figure 260 15a. Fertile lemma with a single long awn or with 3 short awns, or awnless 16 1 5b. Fertile lemma bearing 3 long awns, at least twice as long as the body of the lemma. Fig. 261. Tnchloris criniia (Lag.) Parodi Perennial; tufted; plants 40 — 100 cm. tall; leaf blades 2 — 4 mm. wide. The silvery panicle of spikes is vase-shaped, 5 — 15 cm. long, feathery because of the numerous long awns. Individual spikes are 5 — 10 cm. long. Spikelets disarticu- lating above the glumes; second iloret rudimentary, reduced to awns; lemmas 3-nerved, all of the nerves extending into the awns, which are about 1 cm. long. The plants are sometimes cultivated for ornament. Fields and rocky open groimd. Autumn. Formerly known as Tnchloris mendocina or T. blanchardi- ana. \^ & iife A Figure 261 16a. Spikes borne in one to several whorls, with two to many spikes in each whorl 18 16b. Spikes borne singly at each joint of the rachis 17 138 HOW TO KNOW THE GRASSES 17a. Spikes very long cmd slender (10 — 20 cm. long), the widely-spaced spikelets parallel to the rachis; spikes numerous, forming an open, dome-shaped panicle. Fig. 262. Gymnopogon ambiguus (Michx.) B. S. P. Perennial; tufted or with short rhi- zomes; culms 30 — 60 cm. tall, stiff and erect, with overlapping sheaths and short, broad, spreading leaf blades. The slender spikes may reach 15 — 20 cm. in length, and the whole panicle may be half the total height of the plant. Pine woods, mostly on the Atlantic and Gulf coastal plains. September — November, also in the spring. Figure 262 17b. Spikes thicker, less than 5 cm. long, the closely overlapping spike- lets placed at an angle to the rachis; spikes 1 — many 21 18a. Lenmias light colored, awned. 19 18b. Lemmas dark brown, nearly awnless; spikelets 2 mm. long. Fig. 263. Chloris peiraea Swartz Perennial; tufted or with short stolons; plants up to 100 cm. tall; spikes 4 — 10 cm. long; lemmas chocolate brown; leaf sheaths and culms strongly keeled; leaf blades pale in color and with rounded tips. This species grows in the pine woods of the southern Atlantic and Gulf coastal plains. August — May. Figure 263 139 HOW TO KNOW THE GRASSES 19a. Lemmas without tuits oi white hairs near the apex. 20 19b. Lemmas bearing tuits of long, whitish hairs on the edges near the apex. Fig. 264. FEATHER FINGERGRASS Chloris virgaia Swartz Figure 264 Annual; tufted; culms erect or spreading, 40 — 100 cm. tall; some of the sheaths swollen; leaf blades 2 — 6 mm. wide; spikes 2 — 8 cm. long. The slender, vase-shaped panicles of spikes have a silky, white or pinkish cast because of the numerous long awns and fuzzy lemmas. The fertile lemma is about 3 mm. long. The rudimentary floret is wedge- shaped and bears an awn about the same length as that of the fertile lemma. This species is found as a weed in fields, along roadsides and railroad tracks in the South- west. The occurrences in the eastern states are probably introductions. In New England, the plants occur on wool waste heaps around woolen mills, the seeds being imported in the raw fleeces. July — September. 20a. Plants 1 — 1.5 m. tall; leaf blades tapering to long, fine points. Fig. 265. RHODES GRASS Chloris gayana Kunth Perennial; spreading by leafy stolons; panicles vase-shaped, 5 — 10 cm. long; spikelets yellowish, each with two rudi- mentary florets above the fertile one. Rhodes grass is grown in the southern states for hay and grazing and is found growing wild in fields and on waste ground. It winter kills at 20 degrees F., and so is adapted only to the far South. Introduced from Africa. Figure 26b 140 HOW TO KNOW THE GRASSES 20b. Plants 20 — 50 cm. tall; leaf blades with blunt tips. Fig. 266. WINDMILL GRASS Chloris veTticillata Nutt. Perennial; culms tufted or with short stolons; leaf sheaths flattened and keeled; ligule membranous and ciliate, short; leaf blades grayish-green, 1 — 3 mm. wide; panicles of 2 or 3 whorls of stiff, widely-spreading spikes, each 5 — 15 cm. long. Spikelets rather widely spaced, the spikes slender; spikelets around 3 mm. long; awns 5 — 8 mm. long; fertile lemma hairy on the nerves; rudimentary lemma blunt. Windmill grass is primarily a plant of the plains of the Southwest, but may appear occa- sionally as a waif in the North. The mature panicles break off and roll as tumble weeds. June — September. Figure 266 21a. Inflorescence of 1 — 10 spikes, which remain on the plant; florets dropping from the glumes 22 21b. Inflorescence of numerous spikes, arranged in a slender raceme; entire spikes falling from the rachis whole when ripe. Fig. 267. SIDE-OATS GRAMA Bouteloua curtipendula (Michx.) Torr. Figure 267 Perennial; culms in tufts, arising from slender rhizomes. The plants range up to 80 cm. in height, most of the height being the long raceme of drooping spikes. Late in the season all of the spikes drop from the flattened rachis, which remains, bear- ing only the short stalks of the spikes. Side-oats is a very attractive grass, with brilHont orange anthers, contrasting with the usually purple spikes. The name "side- oats" refers to the fact that most of the spikes droop toward one side of the rachis. This is one of the most valuable forage grasses in the western states, furnishing good feed yearlong. Dry plains and open rocky hillsides, from near sea level to 2700 m. June — September. 141 HOW TO KNOW THE GRASSES 22a. Plants erect or spreading; intemodes of the culms not woolly ... 23 22b. Plants producing elongate stolons, the internodes covered with con- spicuous short white wool. Fig. 268. BLACK GRAMA Boufeioua eriopoda Torr. Perennial; plants sprawling, making bushy clumps, the stems thin and weak, rooting at the nodes. The 2 — 8 spikes are more slender than in the other spe- cies of this genus. Black grama is one of the best forage grasses in the south- western states, furnishing good feed yearlong. Because of its ability to spread by stolons, it stands grazing well and recovers quickly from overuse. Open dry plains and hills, 670 — 1800 m. elevation. July — September. Figure 268 23a. Rachis of the spike bearing spikelets to the tip; keels of glumes usually not black-dotted 24 23b. Rachis of the spike extending beyond the spikelets as a naked point 5 — 8 mm. long; keel of the second glume bearing prominent black dots. Fig. 269. HAIRY GRAMA Boufeioua hirsuta Lag. Perennial; tufted; culms 20 — 60 cm. tall; leaves short, curly, mostly at the base of the plants. Hairy grama is a highly prized forage grass, widespread west of the Missis- sippi, especially on dry plains and hills, from 670—1800 m. elevation. In the Middle West it is usually foimd on dry hilltops. Hairy grama furnishes good feed yearlong, but is especially valued for wintertime use. July — October. Figure 269 142 HOW TO KNOW THE GRASSES 24a. Spikes 3 — 7 per culm, each 1 — 2 cm. long; keels oi glumes without long hairs; shallow-rooted annual plants with soft bases. Fig. 270. SIX-WEEKS GRAMA Bouteloua barbata Lag. Annual; culms 10 — 30 cm. long, in small tufts, erect or more commonly- spreading out and forming flat mats. The seeds germinate after rains, and the plants mature and die rapidly, hence the name "six-weeks grama." The six- weeks grasses, belonging to a nimiber of genera, furnish short-season feed af- ter heavy rains, but their total forage production is small and they are highly undependable as forage plants. Dry plains, especially on overgrazed pas- tures. July — October. Figure 270 24b. Spikes 1 — 3 per culm, each 2.5 — 5 cm. long; keels of second glumes bearing scattered long hairs; perennial, with hard bases. Fig. 271. BLUE GRAMA Bouteloua gracais (H. B. K.) Lag. Perennial; tufted; culms 20 — 100 cm. tall; most of the curly leaves are at the base of the plant. Blue grama is an excellent forage grass on the Great Plains and in the western mountains, furnishing good feed both summer and winter. Open plains, open or lightly timbered moun- tainsides. It may be confused with buf- falo grass (Fig. 247), with which it often grows, but blue grama lacks the creep>- ing stolons of buffalo grass. June — Oc- tober. Figure 271 143 HOW TO KNOW THE GRASSES TRIBE VIII. PHALARIDEAE la. Lower florets less than half as long as the fertUe floret and closely oppressed to it, sterile; glumes usually winged 2 lb. Lower florets as long as the fertile floret or longer 3 2a. Plants producing rhizomes; panicles cylindrical and often lobed. Fig. 272. REED CANARY GRASS Phalaris arundinacea L. Perennial; plants 60 — 150 cm. tall, with pale or purplish panicles, 7 — 16 cm. long. The tall, broad-leaved plants furnish considerable forage and are of- ten cut for hay. They form dense col- onies in marshes and along ditches. Reed canary grass is now planted for erosion control on farm waterways. May — August. Forms with white-striped leaves are sometimes grown for orna- ment, under the name of "gardeners garters." —6? Figure 272 2b. Plants tufted, lacking rhizomes; panicle dense, thimble-shaped. Fig. 273. CANARY GRASS Phalaris canaziensis L. Annual; tufted; culms 30 — 60 cm. tall; pani- cles 1 — 4 cm. long. The strongly winged glumes are striped with green and white hnes. This is the species which furnishes the "canary seed" which is fed to caged birds. The plants are found occasionally growing on trash heaps where the sweepings from bird cages are deposited, but this species ap- parently does not grow as a truly wild plant in this country. Introduced from Europe. June — August. Figure 273 144 HOW TO KNOW THE GRASSES 3a. Lower 2 florets owned, sterile. Fig. 274. SWEET VERNAL GRASS Anthoxanthuzn odozatum L. Figure 274 Perennial; tufted; plants 30 — 60 cm. tall; panicles yellowish-brown, cylindrical, dense, usually less than 6 cm. long; glumes very thin and delicate. The 2 hairy sterile lem- mas are split at the tip and owned from the middle of the back. Sweet vernal grass has the delightful fragrance of coumarin, which persists long after the plants are dried. This species was introduced from Europe, presum- ably as a meadow plant to add fragrance to hay. Now it is widely established as a weed of roadsides, woods, and meadows, except in the dry parts of the United States. It is one of the earUest of spring grasses, blooming from the middle of April to July in the north- ern states. 3b. Lower 2 florets ownless, staminate. Fig. 275. HOLY GRASS HierocWoe odorata (L.) Beauv. h ij Perennial; culms 30 — 60 cm. tall, single or in small tufts, arising from slender creeping rhizomes. Holy grass is an attractive species, with handsome shining golden brown panicles. The glumes are very thin and translucent. The plants have the sweet, vanilla-like scent of coumarin, and were used by the American Indians as material for basketry, and in Europe as perfume in certain religious ceremonies. Moist meadows, bogs, and prairies. April — July. Figure 275 145 HOW TO KNOW THE GRASSES TRIBE iX. ORYZEAE la. Spikelets with evident "glumes/' about 1/3 as long as the lemma and palea. Fig. 276. RICE Oryza sativa L. Annual; plants aquatic, stout, 1 — 2 m. tall; panicles drooping, the very flat spikelets hairy, owned or awnless. The structures which look like glumes are really sterile lemmas; the true glumes are the minute ridges which are left be- hind at the summit of the pedicel when the floret drops. Rice is one of the principal food crops of the world but its culture is restricted to moist or irrigated regions with warm tem- perate or tropical climates. In the United States, it is grown only in the lower Mississippi Basin and in Florida and California. Figure 276 lb. Spikelets without evident glumes 2 2a. Sheaths strongly downwardly scabrous; rhizomes slender, with ex- posed internodes; lower panicle branches whorled. Fig. 277. CUT GRASS Leeisia oryzoides (L.) Sw. Perennial; culms up to 1.5 m. long; weak and often sprawling; rhizomes long and slender; leaf sheaths and margins of the blades armed with very sharp minute spines which can scratch severely. The plants are very rough to the touch and cling readily to clothing. The glumes of species of Leersia are the minute cup-like structures from which the floret drops. Cut grass often forms dense "jungles" along streams or around ponds or in marshes. July — October. Leersia lenticularis Michx. (CATCHFLY Figure 277 GRASS) is similar, but has broadly oval spikelets, 3 — 4 mm. wide and 4 — 5 mm. long, arranged in neat overlapping rows. Wet ground and swamps, Mississippi Valley and southeastern states. 146 HOW TO KNOW THE GRASSES 2b. Sheaths smooth or nearly so; rhizomes short and thick, densely covered with scales: lower panicle branches borne singly. Fig. 278. WHITE GRASS Leersia virginica WUld. Figure 278 Perennial; culms 50 — 120 cm. tall, weak and slender; panicle 10 — 20 cm. long, with a few simple branches, the spikelets lying close- ly parallel to them. Some of the smaller panicles may be hidden in the sheaths. Leaf blades yellowish green. Damp woods and thickets; mud flats. July — October. TRIBE X. ZIZANIEAE la. Plants growing immersed in water, the upper leaves 1 — 5 mm. wide, floating on the water surface. Fig. 279. WATER GRASS Hydrochloa carolinensis Beauv. Perennial; culms slender, weak, up to 1 m. long, floating in water, the upper leaves on the surface. The staminate spikelets are borne at the tips of branches and the pistil- late ones in the axils of leaves. Neither type has evident glumes, and both have only a single floret. Ponds and slow streams. Fur- nishes some feed for livestock. Blooming ap- parently rarely. June — August. Figure 279 147 HOW TO KNOW THE GRASSES lb. Plants with erect tall culms, 1 — 3 m. tall; leai blades 1—4 cm. wide 2 2a. Pistillate spikelets all at the upper tip of the panicle, forming an erect brush; awns of the pistillate spikelets several times as long as the lemma; staminate spikelets all on spreading lower branches of the panicle. Fig. 280. WILD RICE. Zizania aquatica L. Figure 280 Annual; culms stout, 2 — 3 m. or more tall; panicles 30 — 50 cm, long, open and pyramidal. The spikelets consist of single florets, which disarticulate from minute cup-like structures which are the vestiges of glumes. Wild rice was an important food plant for the American Indians, who threshed the standing plants into canoes. It still furnishes some food for human be- ings and the grain can occasionally be purchased in stores. In nature, wild rice is an important producer of food for water fowl. Shallow water, ditches, ponds, streams and marshes. July — September. 2b. Pistillate spikelets intermixed with the staminate ones on the same branches; awns of pistillate spikelets not longer than the lemma. Fig. 281. SOUTHERN WILD RICE Zizaniopsis miliacea (Michx.) Doell. Perennial; plants 1 — 3 m. tall or taller, the culms arising from stout rhizomes; panicles nodding, 30 — 50 cm, long. Leaves very sca- brous on the margins. The spikelets consist of single florets, which disarticulate from the vestigial glumes, as in the previous species. The staminate ones have 6 stamens instead of the usual 3. Marshes and along streams. May — June. Figure 281 148 HOW TO KNOW THE GRASSES TRIBE XI. PANICEAE la. Spikelets inclosed in spiny burs. Fig. 282. FIELD SANDBUR Cenchrus paucifiorus Benth. Figure 282 Annual; culms 20 — 90 cm. long, usually spreading and making mats. The spike- lets are mostly concealed by the horribly spiny burs, which are made up of sterile branches. The burs are borne in short spikes along a zig-zag rachis, and fall off at a touch when ripe. The spines of the burs are very sharp, and each spine is microscopically backwardly-barbed. These spines can inflict painful and dangerous flesh wounds. Each bur contains one to several spikelets, which resemble those of species of Panicum. Sandbur is on unde- sirable weed of disturbed soil, much more common on sandy land than on heavier soils. Where it is abundant, it may furnish some feed for livestock when young. May — October. Cenchrus tribuloides L. (DUNE SANDBUR) has larger burs, 10—17 mm. in diameter. It grows on dunes along the Atlantic and Gulf Coasts. lb. Spikelets not inclosed in spiny burs 2 2a. Spikelets imbedded in one side of an erect, unbranched, flattened, corky rachis. Fig. 283. ST. AUGUSTINE GRASS Stenotaphrum secundatuzn (Walt.) Kuntze Perennial; plants spreading rapidly and ex- tensively by stolons; erect flowering stems 10 — 30 cm. tall. The leaf sheaths are very much flattened and keeled; blades with round- ed, blunt tips. The spikelets are similar to those of Panicum species, but are nearly hid- den by the flanges of the rachis. The first glume and sterile lemma are exposed This unique grass is used for lawns in some locaU- ties in the South. Occasionally plants occur with white-striped leaf blades, and these may be cultivated for ornament. June — September. Figure 283 2b. Spikelets not sunken into the rachis 3 149 HOW TO KNOW THE GRASSES 3a. Each spikelet accompanied by one to many bristles, which are at- tached below it; panicles dense, bristly, spikelike 4 3b. Spikelets without accompanying bristles, borne in open or dense panicles or racemes 1 1 4a. Spikelets (or florets) falling, leaving the bristles on the plant 5 4b. Spikelets falling individually or in groups, with the bristles at- tached to the spikelets. Fig. 284. FOUNTAIN GRASS Pennisefum setaceum (Forsk.) Chiov. Perennial; tufted; culms up to 1 m. tall, with a hairy, pinkish or lavender, spikelike panicle. The panicle is made up of a straight central axis, 15 — 35 cm. long, bearing dense clusters of short branches. At maturity, each branch breaks off, carrying with it a spikelet or a small group of spikelets, surround- ed by a dense tuft of long (3 — 4 cm.) bristles. The larger bristles may have branches, feather-fashion. This is a handsome ornamental grass, introduced from Africa. Summer. Formerly known as P. ruppeJii. Figure 284 Pennisetuui glaucum (L.) R. Br. (PEARL MILLET) has a thick spike, looking like that of the cat-tails. Rarely cultivated for forage in the South. Plants up to 2 m. tall. Bristles of the spikelet-groups short, barely reaching the tips of the spikelets. 5a. Bristles upwardly-barbed or smooth; panicles not clinging to ob- jects * 150 HOW TO KNOW THE GRASSES 5b. Bristles downwardly-barbed, clinging to objects when the panicle is brushed upward. Fig. 285. BRISTLY FOXTAIL Setaria verticillaia (L.) Beauv. Annual; tufted; culms up to 1 m. tall. The barbed bristles of the panicles not only cause them to adhere to wool, hair, or clothing, but also to each other. Af- ter windstorms, the plants will often be densely tangled. Sometimes flies or other insects become caught in the bristles. Common in cornfields and on disturbed soil. June — October. Intro- duced from Europe. Figure 285 6a. Margins of sheaths bearing short hairs 7 6b. Margins of sheaths smooth, thin and translucent; glabrous except for a few long hairs at the apex. Fig. 286. YELLOW FOXTAIL Setaria lutescens (Weigel) Hubb. Figure 286 Annual; tufted; culms spreading or erect, up to 1 m. tall; panicles stiff and compact, with a pronounced golden cast, imparted by the yellow bristles; back of the fertile lemma exposed, trans- versely corrugated. An exceedingly common weed, in cornfields or other disturbed soil. July — October. Intro- duced from Europe. Also known as S. glauca. Setaria geniculata (Lam.) Beauv. has similar panicles but is a perennial, and the culms arise singly or in small tufts from knotty, much-branched rhizomes. Atlantic and Gulf Coast states, from Massachusetts to Texas, lower Mississip- pi Valley to Illinois and Iowa. 151 HOW TO KNOW THE GRASSES 7a. Upper surfaces of leaves glabrous 8 7b. Upper surfaces of leaves covered with soft hairs. Fig. 287. NODDING FOXTAIL Setaria faberii Herrm. Annual; tufted; culms up to 2.5 m. tall; spikelets 2.6 — 2.9 mm. long. This species looks much like green foxtail, but is usually larger and has more drooping, larger pani- cles. The velvety leaf blades are a good mark of recognition. Although known in North America for only about twenty years, nodding foxtail is already a bad weed in parts of the eastern and middle western states. Corn, soybean, and red clover fields; gardens; disturbed soil, especially on river bottomlands. July — September. Introduced from China. Figure 287 8a. Spikelets dropping from the plants whole 9 8b. Fertile floret when ripe "shelling out" of the glumes and sterile lemma, leaving them attached to the plant. Fig. 288. FOXTAIL MILLET Sieiaria italica (L.) Beauv. Annual; tufted; plants stout, often 1 m. or more tall, with large, often definitely lobed panicles. Foxtail millet is regarded as being closely related to the wild green foxtail. The fertile lemma is variously yel- low, orange, red, brown, or blackish. Mil- let is cultivated to a small extent as a forage and grain crop. It is sometimes found persisting after cultivation or as a stray in the wild. Introduced from the Ori- ent. July — October. Figure 288 152 HOW TO KNOW THE GRASSES 9a. Plants usually 1 m. toll or shorter; leaf blades usually 1 cm. wide or narrower; plants widespread, not in coastal marshes 10 9b. Plants 1 — 4 m. tall; larger leaf blades 1 — 4 cm. wide; plants of coastal marshes along the Atlantic and Gulf of Mexico. Fig. 289. GIANT FOXTAIL Setaria magna Griseb. -i Figure 289 Annual; tufted; culms stout and tall, up to 2 cm. thick and 4 m. tall; leaf blades flat and scabrous, up to 50 cm. long. The immense panicles reach lengths of 50 cm. and diameters of 3.5 cm. They are some- what nodding and may be lobed at the base, thickest at the middle and tapering toward the ends. Axillary panicles are much smaller than the terminal one. Bristles 1 — 2 cm. long; spikelets about 2 mm. long; fertile floret smooth and shin- ing, brown when ripe. Giant foxtail is a characteristic plant of coastal marshes, found in the interior only in Arkansas. Its range also extends to the West Indies. August — September. 10a. Plants annual, with soft bases and shallow roots; leaf blades usu- ally less than 15 cm. long, flat; panicles usually less than 10 cm. long, with dense spreading bristles. Fig. 290. GREEN FOXTAIL Setaria viridis (L.) Beauv. Figure 290 panicle branches. Annual; tufted; becoming much-branched from the base, 20 — 100 cm. tall; leaf sheaths glabrous except for the short cilia along the margins; blades glabrous, usual- ly less than 10 mm. wide; panicles soft, sUghtly nodding near the tip; bristles green, rarely purple; spikelets 1.9 — 2.2 mm. long, greenish except when ripe; second glume and sterile lemma nearly covering the fertile floret; fertile lemma nearly smooth. Green foxtail is one of the com- monest weeds of cornfields and other areas of disturbed soil. The bristles are sterile July — October. Introduced from Europe. 153 HOW TO KNOW THE GRASSES 10b. Plants perennial, with hard, knotty crowns; leaf blades usually folded, 15 — 40 cm. long; panicles slender, 2 — 25 cm. long, with sparse bristles. Fig. 291. PLAINS FOXTAIL Setaria macTosiachya H. B. K. Perennial; in hard tufts; culms 40 — 120 cm. tall; panicles slender, with the hairy rachis exposed between clusters of spike- lets. The plants are leafy and are highly palatable to livestock, so that they are usually kept grazed down except in climips of spiny bushes. Dry plains and savan- nas, especially along roadsides or other areas protected from grazing. April — October. Figure 291 11a. Spikelets covered with long, silky, white or brownish or rosy purple hairs 12 lib. Spikelets smooth or hairy with short hairs, or silky on the mar- gins only 13 12a. Spikelets laterally compressed; second glume and sterile lemma awned; hairs rosy purple. Fig. 292. NATAL GRASS; RUBY GRASS RhynchelytTum roseum (Nees) Stopf & Hubb. Perennial; tufted; plants about 1 m. tall; panicles rosy-purple, 10 — 15 .cm. long; spikelets on bent or curled pedi- cels, and densely covered with purple hairs. The second glume and sterile lemma have short awns, which are con- cealed by the hairs. The lateral com- pression of the spikelets is very atypical for the Panicoideae. Dry sandy land and open woods. Natal Grass, an in- troduction from Africa, is grown in Flori- da for forage and has become natural- ized there and also along the Gulf Coast. Winter. Formerly known as Tricholaena rosea. Figure 292 154 HOW TO KNOW THE GRASSES 12b. Spikelets dorsally compressed, awnless; hairs white. Fig. 293. COTTONTOP Trichachne caWoTnica (Benth.) Chase Perennial; tufted, from knotty stooling crowns; plants 30 — 100 cm. tall, with rather dense, slender panicles 5 — 10 cm. long. The panicles have a silvery white color, rarely tinged with purple when young; spikelets with a minute first glume; second glume shorter and narrower than the fertile lem- ma. Cottontop furnishes good summer and winter feed in the Southwest, but is grazed mostly just after rains, when it makes rapid growth. Rocky ridges, margins of fields, in brush. August— October. 13a. Spikelet without a cup or ring at the base; first glume present or absent 14 13b. Spikelet with a cup- or ring-like swelling at the base, without an evident first glume. Fig. 294. PRAIRIE CUP GRASS rriocWoa contracta Hitch. Annual; tufted; culms sometimes de- cumbent; plants 30 — 70 cm. tall. The panicles are slender, made up of nearly erect racemes. The cup-Hke swelling at the base of the spikelet is a modified first glume. The fertile floret is some- what shorter than the sterile lemma and bears a short, hairy awn which is con- cealed within the spikelet. Open ground, moist places, ditches. June — October. There are seven other species of this genus, all rather similar, in the southern states. Figure 294 14a. Glumes or sterile lemma awned (the own sometimes reduced to an abrupt point) 15 14b. Glumes and sterUe lemma awnless. 16 155 HOW TO KNOW THE GRASSES 15a. Lower sheaths glabrous; fertile floret ovoid, 1.9 — 2.2 times longer than wide. Fig. 295. BARNYARD GRASS EchinocWoa pungens (Poir.) Rydb. Annual; tufted; plants robust, up to 1.5 m. tall, with panicles up to 20 cm. long, with spreading branches. The spikelets are covered with stout, spine-like hairs which arise from little yellowish blisters. Disturbed soil, in ditches, fields, marsh- es, borders of ponds. August — Septem- ber. Echinochioa crusgalli (L.) Beauv. is similar but does not have the blister- based stout spines on the spikelets. Just below the withering tip of the fertile lemma is a circle of minute hairs. These are absent in the preceding species. Fields and waste places; widespread; supposedly introduced from Europe. Figure 295 15b. Lower sheaths bristly with stiff hairs; fertUe floret elliptical, 2.5 — 3 times longer than wide. Fig. 296. Echinochoa walteri (Pursh) Nash Annual; tufted; robust, up to 2 m. tall; pani- cles up to 30 cm. long. The spikelets usually bear awns 1 — 2.5 cm. long. Individuals with glabrous sheaths can be identified by the narrow spikelets. Wet ground or shallow water, sometimes in brackish areas, mostly on the Atlantic and Gulf Coastal Plains. Au- gust— September. Figure 296 16a. Spikelets borne in 1 — 4 rows along the lower sides of one or more slender, spikelike racemes 17 16b. Spikelets borne in open or dense panicles, not exclusively on the lower sides of branches 28 156 HOW TO KNOW THE GRASSES 17a. First glume lacking or rudimentary, less than 1/10 as long as the spikelet 18 17b. First glume present, usually more than 1/3 as long as the spike- let. Fig. 297. BrachiaTia platyphylla (Griseb.) Nash Annual; plants stooling out and sometimes rooting at the lower nodes; culms 25 — 40 cm. or more long; leaf blades thickish, 4 — 12 cm. long, 6 — 12 mm. wide; rachis of the racemes flattened, 1 — 2 mm. wide; spikelets glabrous 4 — 4.5 mm. long, the second glume and sterile lemma prolonged beyond the end of the fer- tile floret, forming a soft beak. Moist sandy ground. Summer. Formerly known as B. extensa. Brachiaria ciliatissima (Buckl.) Chase has hairy foUage, and spikelets with woolly sec- ond glume and sterile lemma. It makes mats on dry sandy ground, the prostrate culms rooting at the nodes. Texas, Okla- homa, and Arkansas. 18a. Fertile floret soft and flexible; margins of the lemma not rolled in 19 1 8b. Fertile floret hard and stiff; margins of lemma rolled in 21 19a. Rachis of the racemes thin and flat, with a pro- nounced midrib. Fig. 298 20 19b. Rachis of the racemes triangular in cross section. Figure 298 Fig. 299. Digitaria filifoTznis (L.) Koel. Figure 297 Annual; tufted; culms erect, 10 — 60 cm. tall; racemes 1 — 5, up to 10 cm. long. The first glume is absent, and the equal second glume and sterile lemma nearly cover the chocolate brown fertile floret; spikelets about 1.5 mm. long. Dry, usually sandy disturbed soil. August — October. Figure 299 157 HOW TO KNOW THE GRASSES 20a. Fertile floret brownish-black when ripe; leaf sheaths glabrous. Fig. 300. SMOOTH CRABGRASS Digitaria ischaemum (Schreb.) Muhl. Annual; erect or spreading, often root- ing at the lower nodes; culms usually 15 — 40 cm. long; inflorescence usually of 2 — 6 racemes. This species frequently grows with the next and is a bad weed in lawns. Disturbed soil, fields, waste places, gardens, lawns. Augvist — Oc- tober. Introduced from the Old World. Figure 300 20b. Fertile floret pale or leaden gray when ripe; leaf sheaths sparse- ly to densely covered with long straight hairs. Fig. 301. CRABGRASS Digitaria sanguinalis (L.) Scop. Annual; erect or spreading, usually rooting at the lower nodes; culms up to 1 m. long, the plants often forming large mounds on rich soil. Crab grass is a serious weed in lawns. Being originally from warm climates, it starts growth when hot weather arrives. The rampant plants soon make large patches in lawns, but die out after the first frosts. They also grow abundant- ly in fields and waste places, sometimes furnish- ing some forage. July — October. Introduced from the Old World. Figure 301 21a. Spikelets placed with the back (convex side) of the fertile lemma toward the rachis of the raceme. Fig. 302 22 _>- Figure 302 158 HOW TO KNOW THE GRASSES 21b. Spikelets placed with the fertile lemma turned away from the rachis of the raceme. Fig. 303. CARPET GRASS Axonopus amnis Chase Perennial; producing ejftensive creeping sto- lons; erect culms flattened, 20 — 60 cm. tall; racemes 2 — 5 on each pedimcle, 3 — 10 cm. long; rachis triongiilar in cross section, with the spikelets fitting closely against it. The first glume is absent. Low moist sandy or muck soil on the coastal plain, where it is important as a lawn and pasture grass. March — September. Figure 303 22a. Plants with creeping stems; aquatic or on wet ground. 23 22b. Stems not creeping 24 23a. Leaf blades, sheaths, and spikelets completely glabrous; spike- lets about 2 mm. long. Fig. 304. Paspalum dissecium L. Perennial; plants creeping by extensive sto- lons; erect culms 20 — 60 cm. tall, bearing 2 — 5 racemes, each 2 — 3 cm. long; leaf blades dark green, 3 — 6 cm. long, 4 — 5 mm. wide. The rachis of the raceme is flat and thin, 2 — 3 mm. wide. The first glume is lacking. Muddy flats and ditches and in shallow water. Au- gust— October. Figure 304 159 HOW TO KNOW THE GRASSES 23b. Leaf sheaths with tufts of hairs on the auricles; second glume minutely hairy; spikelets 2.5 — 3.5 mm. long. Fig. 305. KNOTGRASS Paspalum distichuzn L. Perennial; spreading by long creeping stolons; erect culms 8 — 50 cm. tall; inflorescence of 2 or rarely 3 racemes, each 2 — 7 cm. long and some- what curved, attached together at the summit of the culm; spikelets often with a minute first glume. Knotgrass forms large flat mats in ditches and on shores of rivers and ponds, usually in fresh water areas, rarely also in brackish locali- ties. May — September. Found also in South America and Europe. Figure 305 24a. Inflorescences borne at the tips of the culms and in the axils of the sheaths (sometimes hidden within the sheaths) 25 24b. Inflorescences borne only at the tips of the culms, none in the leaf axils or hidden in the sheaths 26 25a. Spikelets 1.5 — 1.8 mm. long, minutely hairy or glabrous. Fig. 306. Paspalum setaceuzn Michx. Perennial; tufted from a knotty crown; plants 30 — 50 cm. tall; hairy; culms slen- der and erect; leaf sheaths hairy; blades up to 12 cm. long and 2 — 6 mm. wide, '> hairy on both surfaces and the edges; inflorescence of 1 or 2 slender, arched racemes, 5 — 7 cm. long; first glume of spikelets lacking. Dry sandy soil and open woods, especially on the Atlantic and Gulf Coastal Plains. July— Septem- ber. Paspalum debile Michx. has spread- ing culms, densely grayish hairy foli- age, and minutely hairy spikelets, 1.8 — 1.9 mm. long. Most of the foliage is at the base of the plant; upper leaves short. Sandy woods of the Atlantic and Gulf Coastal Plains; Long Island to Mexico and Cuba. Figure 306 180 HOW TO KNOW THE GRASSES 25b. Spikelets 2 — 2.4 mm. long. Fig. 307. Paspaluzn pubescens Muhl. Perennial; tuited; plants 40 — 90 cm. tall, hairy; inflorescence consisting of 1 — 3 racemes, each 4 — 17 cm. long; first glume absent. Old fields, meadows, waste groimd, open woods, especially on sandy land. June — September. This is one of the commonest species, and extremely vari- able. There are about four closely related species found in parts of its range. Figure 307 26a. Spikelets not fringed with long hairs 27 26b. Spikelets fringed with long silky hairs, borne on the edges of the second glume. Fig. 308. DALLIS GRASS Paspalum dilatatum Poir Figure 308 hispid lower sheaths, fomia. Perennial; tufted; plants 50 — 150 cm. tall; inflorescence of 3 — 5 racemes, each 6 — 8 cm. long; first glume absent. The spikelets are more pointed than those of most other species. Dallis grass is a -valuable pasture grass in the southeastern states and under irrigation in the Southwest. The spikelets may become infected by an ergot fungus and hence be- come poisonous to cattle. Cultivated mead- ows and pastures and commonly escaped to the wild. May — September. Native to South America. Paspalum urvillei Steud. (VASEY GRASS) is similar but has 12 — 20 racemes and strongly Virginia to Florida, Arkansas and Texas; CaH- 181 HOW TO KNOW THE GRASSES 27a. Plants 1 — 2 m. tall; spikelets 4 — 4.5 mm. long. Fig. 309. Paspalum Uoridanum Michx. Perennial; culms single or in small tufts from short rhizomes; plants robust, 1 — 2 m. tall; foliage hairy or glabrous; inflorescence of 2 — 5 racemes, each 4 — 12 cm. long. The axis of the racemes is strongly zig-zag after the spikelets drop off. First glume absent. Low moist sandy barrens, Atlantic and Gulf Coastal Plains and northward in the interior. July — October. Figure 309 27b. Plants less than 1 m. tall; spikelets less than 3.2 mm. long. Fig. 310. Paspalum laeve Michx. Perennial; tufted; plants 40 — 100 cm. tall- foliage glabrous or hairy. The inflorescence consists of 3 — 4 racemes, each 3 — 10 cm. long. The first glume is absent. This is a com- mon species, varying greatly in hairiness of leaves and shape of spikelets. In typical plants, the spikelets are broadly oval. In var. circulare (Nash) Stone, they are nearly circular. Old fields, waste ground, meadow, open woods. July — October. Figure 310 28a. Second glume not sack-like nor swollen at the base; fertile floret about as long as the second glume and sterile lemma 29 162 HOW TO KNOW THE GRASSES 28b. Second glume sack-like, swollen, the spikelet hence "lop-sided"; fertile floret about half as long as the sterile lemma. Fig. 311. SACK GRASS Sacciolepis striata (L.) Nash Perennial; culms often decumbent and rooting at the lower nodes, up to 2 m. long. The leaf sheaths may be bristly-hairy or smooth. Panicles dense, cylindrical, 6 — 30 cm. long. The spikelets are flat on the first glume side, very bulging at the base on the second glimie side. Ditches, marsh- es and swamps, on the Atlantic and Gulf Coastal Plains. June — December. Figure 31 1 29a. First glume absent or minute, less than 1/10 as long as the spike- let 30 29b. First glume present, usually at least 1/4 as long as the spikelet. 31 30a. Spikelets hairy, 2 — 3 mm. long; no underground spikelets present. Fig. 312. FALL WITCHGRASS Leptoloma cognatum (Schult.) Chase Perennial; plants stiffly spreading or erect, in large tufts; culms 30 — 70 cm. long; panicles very open, with stiffly spreading, thin, somewhat zig-zag branches. The pedi- cels of the individual spikelets may be up to 20 — 30 times the length of the spike- let. The second glume and sterile lemma bear oppressed hairs. When mature, the panicles break off and roll away as tumble- weeds. Dry sandy open soil. May — Sep- tember. Figure 312 163 HOW TO KNOW THE GRASSES 30b. Spikelets glabrous, 4 — 7 mm. long; underground spikelets present on leafless, root-like shoots. Fig. 313. PEANUT GRASS AmphicaTpum purshii Kunth Figure 313 Annual; plants hairy, tufted, erect, 30 — 80 cm. tall. From the crown of the plant arise slender underground runners, 2 — 5 cm. long, each bearing a single large spikelet, 7 — 8 mm. long, at its tip. Most of the seed is produced by these underground spikelets, the aerial panicles being sterile. See also Fig. 330, which shows a subterranean spikelet. Sandy or peat soil, pine barrens of the At- lantic Coastal Plain. Fall. Amphicarpum muhlenbergianum (Schult.) Hitch, is perennial, has smooth leaves and stout underground rhizomes, bearing subter- ranean spikelets. Pine barrens, South Caro- lina to Florida. 31a. Plants blooming twice, bearing panicles at the tips of the culms in spring or early sum- mer, and small axillary panicles later; win- ter rosettes of short, broad leaves present in most species; all perennial species. Fig. 314 32 31b. Plants blooming once, all the panicles pro- duced at the same period; winter rosettes not present; plants annual or perennial ..41 Summer Winter Rosette Figure 314 32a. Leaf blades of the c\ilms less than 15 times longer than wide; plants forming winter rosettes of short, broad leaves 33 184 HOW TO KNOW THE GRASSES 32b. Leaf blades of the culms very narrow, 20 or more times longer than wide; plants without winter rosettes of broad leaves. Fig. 315. Panicum depauperatum Muhl. Perennial; tufted; plants 15 — 40 cm. tall, with hairy or smooth leaf blades, up to 15 cm. long and 2 — 5 mm. wide. The terminal panicles, produced in May and Jime, are open, pyramid-shaped, and on long, slender peduncles. The secondary panicles consist of a few spikelets and are concealed among the basal leaf blades. The second glume and sterile lemma form an empty beak which protrudes beyond the tip of the fertile lemma. Open dry woods and barren ground. May — June. Figure 31 5 33a. Ligules conspicuous, of straight hairs, 2 — 5 mm. long, 34 33b. Ligules 1 mm. or less long. 35 34a. Upper leaf sheaths glabrous; lower sheaths also usually glabrous; leaf blades glabrous or sometimes hairy on the edges only. Fig. 316. Panicum lindheimeTi Nash Perennial; tufted, at first rather slen- der, 30—100 cm. tall. The plants later produce dense tufts of short, leafy branches, in the axils of the leaves, with small secondary panicles partially con- cealed among these leaves. The culms may then topple and the plants form flat circular mats. Terminal panicles blooming from May — July. Open dry ground and dry open woods. Figure 316 165 HOW TO KNOW THE GRASSES 34b. Leaf sheaths and usually the blades conspicuously hairy. Fig. 317. Panicuin implicatum Scribn. Perennial; tufted; plants 15 — 75 cm. tall, with open, pyramid-shaped terminal panicles blooming in May and June. Later the plants become much-branched, with loose axillary tufts of short leafy branches, interspersed with the short secondary panicles. Roadsides, old fields, open woods, meadows, swamps. Very common and widespread. Panicum implica- tum is usually broken up into a number of scarcely distinguishable "species" by other authors. P. columbianum (see Fig. 324) is quite similar. Figure 317 35a. Plants smooth or somewhat hairy, never velvety to the touch .36 35b. Culms, leaf blades, and sheaths softly velvety to the touch, gray- ish; a smooth, sticky ring is present below each node. Fig. 318. Panicum scoparium Lam. Perennial; tufted; plants 80—130 cm. tall; leaf blades large, 12—20 cm. long and 10—20 mm. wide. The terminal panicles are open, elliptical, up to 15 cm. long, produced in June and July. Later the plants become branched, with loose bunches of leaves in the axils of the sheaths of the main culm. Th^ small secondary panicles are partially concealed among these branches. Low moist soil, mostly on the Atlantic Coastal Plain and northward in the Mississippi Valley. Figure 318 36a. Spikelets over 3 mm. long. 37 36b. Spikelets 2.7 mm. or less long. 38 166 HOW TO KNOW THE GRASSES 37a. Upper leaf sheaths bristly hairy with spreading hairs; leaf blades 6—12 mm. wide. Fig. 319. Panicum scribnerianuzn Nash Perennial; tufted; plants 20 — 50 cm. tall, rather stiff; sheaths sparsely covered with stiff spreading bristles or nearly smooth. The terminal panicles, produced in May and June, are 4 — 8 cm. long and about as broad, pyra- mid-shaped. After the terminal panicles have shed their spikelets, the plants become bushy- branched and produce small, simple panicles partially concealed by the tufted upper leaves. Prairies and open woods, often on dry sandy soil. Figure 319 37b. Upper sheaths glabrous or softly hairy; larger leaf blades 1.5 — 4 cm. wide. Fig. 320. Panicum latifolium L. Perennial; tufted; 45 — 100 cm. tall; terminal panicles produced in June, about 10 cm. long and nearly as wide, with stiff spreading branches; spikelets hairy, 3.4 — 3.7 mm. long. This is one of the most easily recognized of all grasses. The very broad leaf blades are heart-shaped at the base. Roadsides, woods, stream banks. The following species are also wide-leaved. Panicum clandestinum L. has very bristly sheaths on the secondary branches. Spike- lets 2.7 — 3 mm. long. Panicum boscii Poir. has spikelets over 4 mm. long. The nodes of the stems are beard- ed with soft hairs, and the foHage is some- times hairy. Figure 320 38a. Culms glabrous 39 38b. Culms covered with short fuzz and sometimes with longer hairs . . 40 167 HOW TO KNOW THE GRASSES 39a. Spikelets glabrous, narrowly elliptical. 1.8 — 2.2 mm. long; leaf blades not hairy on the margins. Fig. 321. Panicuzn dichotomum L. Perennial; tufted; plants erect, 30 — 50 cm. tall, glabrous or with a ring of hairs on the lower nodes; terminal panicles in June, 4 — 9 cm. long, with spreading branches. Later the culms become much branched from the middle nodes, appearing Uke Uttle trees and sometimes falling from their weight. The sec- ondary panicles are small, with few spikelets. They extend sUghtly above the leaves of the branches. Widespread and common in rocky woods and on brushy land. Panicum microcarpon Muhl. has strongly bearded nodes and tiny spikelets, 1.5 — 1.7 mm. long. Moist woods, meadows, and swamps. Figure 321 39iD. Spikelets minutely hairy, broadly obovoid at maturity, 1.5 — 1.8 mm. long; leaf blades 7 — 14 mm. wide, with long marginal hairs at the base. Fig. 322. Panicum sphaerocarpon Ell. Perennial; tufted; culms 20 — 55 cm. long, erect or spreading; plants glabrous except for the few hairs at the base of each leaf blade, and often somewhat glaucous. Leaf blades rather broad, the top one 4 — 9 mm. in width. The broad panicle is less than twice as long as wide. Dry open ground and thin woods. Terminal panicles in June and July. Panicum polyanthes Schult. has a longer, elhptical panicle, 2 — 4 times longer than wide, and an uppermost leaf 9 — 28 mm. wide. Open woods and damp ground. Southern New England to Oklahoma and Figure 322 southward. 168 HOW TO KNOW THE GRASSES 40a. Spikelets 2.2 — 2.7 mm. long; leaf sheaths glabrous; culm inter- nodes covered with short, bent hairs. Fig. 323. Panicum ashei Pearson Perennial; tufted; plants stiffly erect, 25 — 50 cm. tall. The pyramid-shaped primary panicles are 5^8 cm. long and have rather few spikelets. The internodes of the culms and portions of the leaf blades tend to be purple. The plants become rather spar- ingly branched, with elongated branches. Dry rocky woods, brushland, often on sandy ground. Primary panicles produced from May to July. Figure 323 40b. Spikelets 1.5 — 1.9 mm. long; leaf sheaths hairy; at least some of the sheaths and internodes covered with a mixture of long hairs and short, fine fuzz. Fig. 324. Panicum coluznbianum Scribn. Figure 324 Perennial; tufted; plant 15 — 50 cm. tall; leaf blades 3 — 6 cm. long, 3 — 5 mm. wide, the upper surface glabrous and the lower with fine, short hairs; primary panicles ovoid, 2 — 7 cm. long, produced in June and July. Later the plants become much-branched and bushy, often making mats on the ground. Dry sandy or rocky sterile ground, in the open or in thin woods. Panicum meridionale Ashe. Plants small and delicate; leaf blades 1.5 — 3 cm. long, 2 — 4 mm. wide; upper surfaces of leaves bearing long, erect hairs; spikelets 1.3 — 1.5 mm. long. Sterile soil; N. S. to Minn., Ga., and Ala. 41a. Spikelets glabrous or hairy, never warty. 42 169 HOW TO KNOW THE GRASSES 41b. Spikelets glabrous, covered with minute warts. Fig. 325. Panicum verrucosum Muhl. Annual; plants sprawling, the culms branching and rooting from the lower nodes, up to 150 cm. long. The entire herbage is glabrous except for the margins of the sheaths; leaf blades thin, bright green, 5 — 20 cm. long, 4 — 10 mm. wide; ligules very short, hairy; panicles up to 30 cm. long, very open, the small (about 2 mm. long) spikelets borne in groups of 1 — 3 near the ends of the branches. Banks of streams; moist sandy or peaty soil. July — September. Panicum brachyanthum Steud. has nar- rower leaf blades, 2 — 3 mm. wide; pointed spikelets 3.2 — 3.6 mm. long, covered with wart-based hairs. August — September. Arkan- sas and Oklahoma to Louisiana and Texas. Figure 325 Figure 326 42a. Fertile lemma minutely cross-wrinkled. Fig. 326. 43 42b. Fertile lemma smooth and shining 44 43a. Spikelets 5 — 6 mm. long, hairy. Fig. 327. TEXAS MILLET; COLORADO GRASS Panicum texanum Buckl. Annual; culms hairy, erect or decumbent and rooting at the lower nodes, usually 50 — 150 cm. long; leaves 7 — 16 mm. wide, 10 — 20 cm. long, softly velvety; leaf sheaths velvety; Hgule hairy, about 1 mm. long; panicles narrowly cylindri- cal, 7 — 25 cm. long, up to 3 cm. in diameter; rachis and branches hairy. The lush, vigorous plants make good forage. They occur along streams and in com and cotton fields. The com- mon name, Colorado Grass, apparently refers to the Colorado River of Texas, since this species does not occur in the state of Colorado. June — September. Panicum arizonicum Scribn. and Merr, has similar spikelets, 3.5 — 3.8 mm. long; blades 6 — 12 mm. wide; panicle more open, with hairy branches. Western Texas to CaHfomia and Mexico. August — Sep- tember. Figure 327 170 HOW TO KNOW THE GRASSES 43b. Spikelets 2 — 4 mm. long, glabrous. Fig. 328. BROWNTOP MILLET Panicum iasciculatum Swartz Annual; tufted, rather bushy; culms 30 — 100 cm. long; leaf blades 6 — 20 mm. wide, gla- brous; ligule of hairs, 1 mm. long; sheaths glabrous or papillose-hairy; panicles 5 — 15 cm. long, made up of simple branches 5 — 10 cm. long, the spikelets nearly sessile on the branches; spikelets frequently yellowish or brown, 2 — 3 mm. long, with pronounced cross- veins between the longitudinal ones. Var reticulatum (Torr.) Beal has pubescent leaf blades, 6 — 10 mm. wide; spikelets 2.6 — 3.2 mm. long. These plants are common weeds in fields, on river flats, and on waste ground. May — September. Figure 328 44a. Plants without stolons; first glume much shorter than the whole spikelet 45 44b. Plants producing long, wiry stolons; spikelets very blunt, the first glume nearly as long as the spikelet. Fig. 329. VINE MESQUITE GRASS Panicum obtusum H. B. K. Figure 329 Perennial; producing elongated stolons up to 3 m. or more in length, their nodes hairy, swollen; culms erect, flattened, 20 — 80 cm. tall, with glabrous nodes; leaf blades 2 — 7 mm. wide, glabrous; Hgules 1 mm. long, membranous; panicles 3 — 12 cm. long, very narrow, with a few ascending branches; spikelets crowded, 3 — 3.8 mm. long, glabrous, brownish; sterile lemma containing a palea and a staminate flower. Banks of streams, ditches, dry wash as, irrigated fields. Vine mesquite furnishes some grazing, especially in the spring. It is sometimes planted for erosion control, especially on terrace outlet channels, spillways of earth dams, and flood plain flats. lune — September. 171 HOW TO KNOW THE GRASSES 45a. Plants producing underground spikelets on root-like underground branches; aerial panicles sterile. Fig. 330 30b 45b. Plants lacking iinderground spikelets; panicles fer- tile 46 46a. Panicles with spreading or drooping branches; rhi- zomes present or absent 47 Figure 330 46b. Panicles long and slender, with erect branches; plants producing extensive rhizomes. Fig. 331. MAIDEN CANE Panicum hemitomon Schult. Perennial; culms hard and stiff, 50 — 150 cm. tall; sheaths smooth or bristly; leaf blades 10 — 25 cm. long, 7 — 15 mm. wide, scabrous on top; panicles slender and spikelike, 15 — 30 cm. long; spikelets 2.3 — 2.7 mm. long. Wet ground and in water; ponds and ditches, wet fields, on the At- lantic and Gulf Coastal Plains. Sometimes maiden cone becomes a weed in wet fields. April — July. Figure 331 47a. Panicle much-branched, open, the spikelets usually on long stalks, not confined to the lower sides of the branches; fertile lemma not hairy at the tip 48 47b. Panicle with mostly unbranched main branches, the spikelets on short stalks, mostly on the lower sides of the branches; fertile lemma with a tuft of minute stiff hairs at the tip 51 48a. Sheaths covered with stiff spreading hairs 49 48b. Sheaths glabrous 50 172 HOW TO KNOW THE GRASSES 49a. Spikelets 3.5 mm. long or shorter; panicle branches slender, stiii. Fig. 332. WITCH GRASS Panicum capUlare L. Annual; tufted; becoming bushy-branched, often a meter or more tall; foUage soft; leaf blades hairy on both surfaces, 5 — 15 mm. wide; terminal panicles large, dome-shaped, often more than half the length of the plant; numerous axillary panicles also present; bases of panicles usually hidden in the sheaths; axils of main panicle branches bear- ing tufts of hairs; panicles at maturity break- ing away from the plant and rolling away as tumbleweeds. This is one of the commonest weedy grasses of fields and disturbed soil- widespread in the United States. About eight similar species are found in various parts of the country, but are much less common. July — October. Figure 332 49b. Spikelets 4.5 mm. or more long; panicle branches stout, drooping. Fig. 333. BROOMCORN MILLET; PROSO MILLET Panicum miliaceum L. Annual; tufted; plants 20 — 100 cm. tall; foli- age coarsely hairy or nearly smooth; leaf blades up to 30 cm. long and 20 mm. wide; panicles 10 — 30 cm. long, drooping, the branches scabrous; spikelets 4.5 — 5 mm. long, plump; fertile lemmas yellow, reddish, or brown. Proso is grown sparingly in the United States for forage, hog feed, and bird seed. The plants occur as strays on waste ground. Proso is probably native to Asia. It is cultivated in the Orient, and to a lesser extent in Europe. It is supposed to be one of the most ancient of cultivated crops, and was known to the Romans under the name of Milium, whence comes our word millet. July — September. Figure 333 173 HOW TO KNOW THE GRASSES 50a. First glume rounded or broadly triangular, 1/4 — 1/3 as long as the spikelet; plants annual, without rhizomes. Fig. 334. FALL PANICUM Panicuzn dichotomifloTum Michx. Annual; tufted; plants bushy, with freely branching erect or spreading culms; often coarse, with culms up to 2 m. long in vigor- ous specimens; stems often zig-zag, with an axillary panicle at each upper node. This is a common weed of cultivated fields, waste ground and moist soil around ponds or along streams. The size of the plants varies greatly, depending upon the moisture and fertiUty of the soil. July — October. Figure 334 50b. First glume at least half the length of the spikelet, tapering to a sharp point; plants perennial, with hard, rhizome-producing bases* Fig. 335. SWITCH GRASS Panicum virgatum L. Perennial; in clumps, spreading by thick scaly rhizomes; culms strong, 1 — 2 m. tall; panicles large and open, 15 — 50 cm. long; spikelets 3.5 — 5 mm. long, often reddish in color and at times appearing laterally compressed. Switch grass is one of the most important native grasses of the tall grass prairie, but occurs far beyond the prairie area as well. Prairies, open ground, river banks and bottomlands, thin woods. A valuable forage species, sometimes harvested as a part of wild prairie hay. July — October. Figure 335 174 HOW TO KNOW THE GRASSES 51a. Plants producing rhizomes; spikelets scythe-shaped, set at an angle to the pedicel. Fig. 336. Panicum anceps Michx. Perennial; short scaly rhizomes present; culms erect, 50 — 100 cm. tall; leaves smooth or hairy, elongated, 4 — 12 mm. wide; pani- cles open, 15—40 cm. long; spikelets 3.4 — 3.8 mm. long, curved. Open moist ground and woods, especially on sandy soil. July — September. Panicum rhizomatum H. & C. is similar but has more elongated rhizomes, contract- ed panicles, and spikelets 2.4 — 2.8 mm. long. Sandy soil on the Atlantic and Gulf Coastal Plains, Maryland to Texas; Ten- nessee. Figure 336 51b. Plants without rhizomes; spikelets straight or nearly so, set in line with the pedicel. Fig. 337. Panicum agrostoides Spreng. «// Perennial; tufted; culms 50 — 100 cm. tall- panicles elliptical, the branches densely clus- tered with nearly sessile spikelets; spikelets green or somewhat reddish, 1.8 — 2.2 mm. long. Moist shores and meadows, swamps, alluvial mud flats. July — September. Panicum condensum Nash is similar but has a denser panicle; spikelets 2.2 — 2.5 mm. long. Wet ground on the Coastal Plains, Pennsyl- vania to Florida and Texas. Figure 337 175 HOW TO KNOW THE GRASSES TRIBE XII. ANDROPOGONEAE la. Both spikelets of each pair on stalks 2 lb. One spikelet of each pair sessile 4 2a. Racemes single on each peduncle; awns hairy lib 2b. Racemes several to many on each peduncle; awns absent or smooth 3 3a. Inflorescence narrow, spikelike; spikelets awnless. Fig. 338. SATINTAIL Iznperata bTeviiolia Vasey Perennial; culms arising from hard scaly rhizomes; culms 1 — 1.5 m. tall, with elongated leaves and slender, silvery-hairy panicles, 15 — 35 cm. long and 1 — 3 cm. thick. The spike- lets are about 3 mm. long and have a ring of long white hairs at the base, with some hairs also attached to the backs of the glumes. The spikelets fall from the rachis when ripe. Deserts. July — September. Imperata cylindrica (L.) Beauv. (COGON GRASS) has been introduced in western Flori- da. Spikelets 4 — 5 mm. long. This species has forage uses but may become a weed, Figure 338 because of its extensive rhizomes. 3b. Inflorescence fan-shaped; spikelets with awns. Fig. 339. EULALIA Miscanthus sinensis Anderss. Perennial, forming large clumps; culms 2 — 3 m. tall, with plumeHke, silvery-gray, fan-shaped panicles of long, hairy racemes. The spikelets are about 5 mm. long, with a ring of hairs about as long as the spike- let, attached at the base of the glumes. The spikelets fall from the rachis when ripe. Cultivated widely as an ornamental, and escaping to the wild occasionally around inhabited places. Horticultural forms with white striped or cross-banded leaves are also grown. September — Oc- tober. Native to Asia. Figure 339 176 HOW TO KNOW THE GRASSES 4a. Each raceme* of spikelets consisting of many pairs of spikelets; racemes solitary or variously grouped 5 4b. Each raceme* consisting of 1 — 3 pairs of spikelets; racemes grouped into an open or dense panicle 15 5a. Both spikelets of each pair alike and with perfect florets 6 5b. One spikelet of each pair perfect, the other either staminate, sterile, reduced in size, of a different shape, or nearly absent 7 6a. Spikelets with awns; wild plants. Fig. 340. SILVER PLUMEGRASS Erianthus alopecuroides (L.) Ell. Figure 340 Perennial; culms strong and tall, 1 — 3 m. long, arising from short, scaly rhizomes. The nodes, upper portions of the sheaths, and peduncles are oppressed-hairy. The dense silky-hairy elliptical panicles are 20 — 30 cm. long. Each yellowish spikelet bears a tuft of long silvery or purplish hairs from the base, as well as a few hairs on the upper portions of the glumes. Spikelets 5 — 6 mm. long, with a flattened and twisted awn 1 — 1.5 cm. long. The rachis breaks up into individual joints when ripe. Open woods, wet low ground, hammocks. September — October. Erianthus contortus Ell. is similar, but has dark brown glimies. Erianthus giganteus (Walt.) Muhl. (E. saccharoides) is similar but has straight, untwisted awns which are not flattened in crosss section. ♦According to strict definition, these inflorescence branches are not racemes, because they have some sessile spikelets, but this term is usually used. 177 HOW TO KNOW THE GRASSES €b. Spikelets without awns; cultivated plants. Fig. 341. SUGAR CANE Saccharum oiiicmarum L. Perennial; tall stout plants, with culms 3 — 5 m. tall and up to 3 cm. thick. The stiff, elongated leaves have very sca- brous cutting edges. Panicles large and plumelike, 20 — 60 cm. long. The ra- cemes break up into individual joints when ripe, with a pair of spikelets at- tached to each joint. Sugar cane is widely cultivated in the tropics for the production of sugar, but in the United States is grown only in the southern end of the Mississippi Valley and in Florida. The plants seldom bloom. Eiianthus ravennae (L.) Beauv. (RAVENNA GRASS) has a large, plumehke panicle, up to 60 cm. long, and slender culms up to 4 m. tall. Cultivated for ornament and hardy in the southern half of the country. 7a. Pedicels and rachis joints thickened at the upper ends, closely pressed together or united; spikelets awnless 8 7b. Pedicels and rachis joints not evidently thickened, not pressed to- gether nor united; spikelets awnless or owned 9 Ba. Perfect spikelet spherical, with a rough pitted surface; rachis joint and pedicel united. Fig. 342. Hackelochloa granularis (L.) Kuntze Figure 341 Figure 342 Annual; tufted; culms 30 — 100 cm. tall, much branched. The culms have numerous axillary racemes; sheaths and culms covered with hairs which arise from Httle blisters. The spikelets are borne in spikes or racemes, 1 — 2 cm. long, the individual spikelets being 1 — 2 mm. long. The racemes break up into individual joints, each bearing a sessile perfect spikelet which is blackish, and a strongly laterally compressed and winged staminate spikelet, which is green or reddish in color. This unusual grass is a native of the Old World tropics, but has been introduced into our southern states. It may yield some forage. Fall. 178 HOW TO KNOW THE GRASSES 8b. Perfect spikelet lanceolate, smooth or rough; rachis joint and pedi- cel separate. Fig. 343. Manisurus rugosa (Nutt.) Kuntze Figure 343 Perennial; culms from hard, knotty crowns; culms flattened, much branched, 70 — 120 cm, tall, with numerous axillary racemes. Ra- cemes slender, "rat-tail"-like, brownish, 4 — 8 cm. long, tapering from the middle toward the base and apex. They break up into in- dividual joints readily, each joint bearing a perfect sessile spikelet and a sterile spikelet on a thickened pedicel. The first glume of the spikelet is strongly corrugated across the width. Wet pine woods and bogs, Atlantic and Gulf Coastal Plains. September. Four other similar species are found in the south- ern states, differing in the degree of rough- ness, pitting, etc. of the first glume. 9a. One raceme on each peduncle 10 9b. Several to many racemes on each peduncle 12 10a. Awns hairy, stiff and strong, 3 — 12 cm. long; awned spikelets bearing a sharp hairy callus at the base 11 10b. Awns not hairy, thin and delicate, 2 cm. long or shorter; spike- lets disarticulating at the base of the glumes 12b 11a. One awned and one awnless spikelet falling as a pair; rachis of the raceme disarticulating. Fig. 344. TANGLEHEAD Heferopogon contoTtus (L.) Beauv. Perennial; tufted; plants 20 — 80 cm. tall; leaf sheaths flattened and keeled; racemes borne at the tips of slender peduncles. The pairs of spikelets at the base of each raceme are all staminate. In the upper portion of the raceme, each pair consists of a sessile perfect spikelet and a stalked staminate spikelet. The sessile spikelet has a long, bent awn and a hairy rachis joint, which is attached below the base of the glumes. This spikelet greatly resembles the floret of some species of Stipa. Attached at the base of the perfect spikelet is a short pedicel bearing an awnless, laterally compressed and winged staminate spikelet. The two spikelets of each pair fall as a unit. Because of the sharp hairy callus and stiff awn, the perfect spikelets may injure graz- ing sheep. A good forage grass when not in fruit. Rocky deserts in Figure 344 179 HOW TO KNOW THE GRASSES the Southwest; found throughout the tropics of both Old and New World. June — September. Heteropogon melanocarpus (Ell.) Benth. has staminate spikelets with glabrous glumes, a row of glandular spots running down the middle of the glume. Southeastern states and Arizona. lib. Awned spikelets falling, awnless ones remaining on the persistent rachis of the raceme. Fig. 345. CRINKLE AWN Trachypogon secundus (Presl) Scribn. Perermial; tufted; 60 — 120 cm. tall; herbage nearly smooth but the nodes bearing a circle of stiff, erect hairs. The erect slender raceme is 10 — 20 cm. long. The rachis remains whole with the short-pedicellate or sessile staminate spike- lets attached to it. The longer-pedicellate per- fect spikelets break from the rachis with their hairy, rigid pedicels attached. The perfect spike- let looks very much like the floret of some spe- cies of Stipa. The lemma is 6 — 8 mm. long, with a bent and twisted awn 3 — 6 cm. long. Rocky dry hills. May — October. Figure 345 12a. Racemes several to many on each pedimcle 13 12b. Racemes one on each peduncle. Fig. 346. LITTLE BLUESTEM Andropogon scoparius Michx. Perennial; tufted; plants green or red- dish, 50 — 150 cm. tall; foUage smooth or hairy. The racemes are borne on slender peduncles from the axils of the sheaths and the tips of the culms. The rachis joints and pedicels are strongly hairy. Little bluestem is characteristically a plant of dry prairies and plains, but occurs to some extent over nearly the entire United States. Prairies, old fields, rocky slopes and open woods. Little bluestem furnishes much grazing in the Middle West and West, especially for cattle and horses. August — October. Figure 346 Nine other species, similar in having only one raceme on each peduncle, occur in the southern United States, but are much rarer. 13a. Stalked spikelet sterile, rediiced to a small rudiment or nearly absent; racemes feathery, white 14 180 HOW TO KNOW THE GRASSES 13b. Stalked spikelet staminate, similar to the sessile one but awn- less; racemes green or purplish in color, not feathery with fine hairs. Fig. 347. BIG BLUESTEM Andropogon gerardi Vitman Perennial; tufted or with short rhi- zomes; plants green or reddish, 1 — 2 m. tall or even taller; foHage sometimes hairy. The plants bear 3 — 6 reddish racemes at the tip of the culm, and usu- ally some smaller inflorescences from the axils of the leaves. Big bluestem was one of the principal grasses of the tall grass prairie which produced the rich soils of our com belt. Very Httle of such grassland still exists, but this species is still very common on untilled land in the prairie area. Farther east it is less common, but occurs on steep slopes, in meadows, and along river banks. This is an important forage species, and still provides much wild hay from native prairie. August — October. Also known as A. furcatus and A. provincialis. Andropogon hallii Hack. (SAND BLUESTEM) has more elongated rhizomes and yellowish spikelets. Sandhills of the Great Plains and Rocky Mountain area. 14a. Inflorescence of two to four racemes, which are inclosed at their bases by a leaf sheath. Fig. 348. BROOMSEDGE Figure 347 Fern.). Andropogon vjrginicus L. Perennial; tufted; 50—100 cm. tall; foli- age smooth or somewhat hairy, often red- dish; culms bearing feathery-hairy inflor- escences at the tip and from the axils of the leaves of the upper half of the culm. Broomsedge is a plant of sterile open hill- sides, abandoned fields, and thin woods. It usually indicates poor soil. The forage value is apparently low, especially when the plants are mature. August — October. About fourteen other similar species or varieties occur in the southeastern states, mostly on the coastal plain. Most striking of these is the following. Andropogon glomeratus (Walt.) B. S. P. (A. virginicus, var. abbreviatus (Hack.) the inflorescences are condensed into a dense, broom-Hke Figure 348 All 181 Figure 349 HOW TO KNOW THE GRASSES cluster at the top of the stem. Southeastern states; Texas to California, often on damp, low ground. 14b. Inflorescence a terminal panicle of numerous racemes; leafy bracts absent from the panicle. Fig. 349. SILVER BEARDGRASS Andropogon saccharoides Sw. Perennial; tufted; rather bushy; culms 60 — 130 cm. tall; foliage usually glabrous, becoming reddish when mature. The long- stalked panicles are silvery white, oblong, 7 — 15 cm. long. The rachis joints and pedicels are fringed with long white hairs. Sessile spikelet of each pair about 4 mm. long, the pedicellate one rudimentary. Sil- ver beardgrass and several of its close relatives are valuable forage grasses in parts of the Southwest, but are easily ex- terminated by overgrazing. Prairies and plains, rocky slopes, draws and dry wash- es, often on sandy soil. June — September. Andropogon perforatus Trin. has a small "pinhole" pit in the center of the first glume. Texas and Mexico. Andropogon barbinodis Lag. is taller, with a short, fan-shaped pani- cle, with spikelets 5 — 6 mm. long. The nodes of the culms are promi- nently bearded. Oklahoma to California and Mexico. 15a. Stalked spikelets present, staminate 16 15b. Stalked spikelets lacking, only the hairy pedicel present. Fig. 350. INDIAN GRASS SorghastTum nutans (L.) Nash Perennial; in tufts from short rhizomes; plants 1 — 2.5 m. tall; foliage usually smooth. Panicles narrow and rather dense, 15 — 30 cm. long. The panicle has a "gold- and-silver" aspect because of the yellow, 5 — 6 mm. long spikelets and the copious white hairs which fringe the rachises and pedicels. The prominent anthers are gold- en yellow. The panicle is made up of short racemes of 1 — 3 joints. Each sessile spikelet is accompanied by a hairy pedi- cel. The racemes break up into individual joints at maturity, each bearing a spikelet and a rachis joint and pedicel. Indian grass is one of the principal grasses of the tall grass prairie. It is also found in the eastern states and the Rocky Mountains. It forms an important com- ponent of wild prairie hay. Prairies, plains, stream banks, dry hills. July — September. Figure 350 182 HOW TO KNOW THE GRASSES 16a. Spikelets when ripe disarticulating from the tip of the pedicel; end of pedicel cup-shaped; rhizomes present; weed. Fig. 351. JOHNSON GRASS Sorghum haiepense (L.) Pers. Perennial; culms tall and stout, 0.5 — 2 m. tall, arising from thick, widely- spreading rhizomes; panicle open, pyra- mid-shaped, 15 — 50 cm. long. The ses- sile spikelet is perfect and fertile, hard, and rather plump, about 5 mm. long. The awn falls off readily, so the spike- lets are often awnless. The pedicellate spikelets are of softer texture, staminate, narrower, and awnless. The sessile spikelet at the end of each short raceme is accompanied by two pedicellate spikelets. The fertile spikelets vary from straw-colored to almost black. This species, regarded as a noxious weed in the southern states, is very similar to the annual crop, Sudan grass. Despite its bad traits, John- son grass furnishes a great deal of forage and is readily eaten by Uvestock. Eurasian. 16b. Spikelets when ripe breaking from the plant with the upper end of the pedicel, leaving a jagged stub; rhizomes lacking; crop plant. Fig. 352. SUDAN GRASS Sorghum sudanense (Piper) Stapf Figure 351 Annual; tufted; culms 1 — 3 m. tall. The plants resemble those of Johnson grass but lack the rhizomes. Widely cultivated for annual pasture and hay and sometimes found as a stray from dropped seed. Native to North Africa. Sorghum vulgare Pers. (SORGHUM) This species includes a large group of rather corn- like plants, cuhivated in warm sections of the country for grain, fodder, silage, and syrup. The leaves and stems greatly resemble Indian com, but the spikelets, similar to those of Johnson grass, are all borne in panicles at the tips of the stems. The grains may be black, brown, reddish, gray, or white. In many varieties, the grain becomes large enough to burst out of the glumes. Milo, hegari, feterita, durra, kafir com, shallu, amber cane, broomcorn, etc. are all varieties of this spe- cies. Broomcom is not used for forage, but the stiff, elongated panicle branches are the broomstraw of commerce. Figure 352 183 HOW TO KNOW THE GRASSES Figure 353 TRIBE XIII. TRIPSACEAE la. Pistillate spikelets borne in hard, bony beads, each bead on a separate stalk; staminate spikelets protruding on a stalk from the opening of the bead. Fig. 353. JOB'S TEARS Coix lacryma-jobi L. Annual; plants coarse, somewhat corn- like, up to 1 m. tall, abundantly branch- ing from the upper nodes. Each peduncle bears a hard, shiny, white, grayish, or black bead, from the upper end of which protrudes a short inflorescence consisting of few joints bearing sessile and pedicel- late staminate or sterile spikelets, in some- what irregular combinations. Staminate spikelets consist of 2 glumes, inclosing 2 staminate florets. Within the bead is borne a single pistillate spikelet and 2 slender, tubular, sterile spikelets, along with the stalk of the staminate inflorescence. The stigmas protrude from the mouth of the bead. The staminate inflorescence breaks away and the beads fall from the plant when ripe. Job's tears is cultivated as a curiosity, and for the "beads," which are used in rosaries and jewelry. The plants may be found in the wild in the southern states. Introduced from the tropics of the Old World. Late summer. lb. Pistillate spikelets borne in spikes or on cobs, never separately . . 2 2a. Staminate spikelets borne at the tip and pistillate spikelets at the base of the same spike: pistillate portion of the spike hard and bony; husks not present. Fig. 354. GAMA GRASS TTipsacuzn dactyloides L. Perennial; in large clumps, from thick rhi- zomes. The plants reach 2 — 3 m. in height. The spikes are borne singly or 2 — 3 together at the tips of long leafless peduncles. The basal portion of each spike consists of a ser- ies of hardened, smooth, hoUowed-out joints, each nearly inclosing a single pistillate spike- let. These joints break apart readily when ripe. The upper portion of each spike is made up of a series of joints, each bearing 2 sessile staminate spikelets. This portion of the spike is shed whole when the pistillate rachis breaks up. Gama grass is a close relative of corn and has been experimentally crossed with it. The plants are leafy and may produce some forage, but they are sel- dom abundant. River banks and moist ground. June — October. Figure 354 184 HOW TO KNOW THE GRASSES Figure 355 2b. Staminate spikelets in a "tassel" at the stem tips; pistillate spike- lets on a many-rowed axillary "cob," surrounded by leafy husks. Fig. 355. MAIZE; INDIAN CORN Zea mays L. Annual; tufted; plants exceedingly variable in ^^^^ \\W/ ^^^® °^^ habit, but char- v'/>r>C'\ \Y acteristically with thick, solid stalks. The pistil- late inflorescence (ear) has paired rows of spike- lets. The glumes, sterile and fertile lemmas form the "chaff" that remains on the cob. In a few va- rieties, such as Country Gentlemen, both florets of each pistillate spikelet develop grains, produc- ing very crowded and ir- regular rows. Corn is unusual in having united styles, which form the "silk." The staminate in- florescence (tassel), is much-branched and bears pairs of spikelets, one of each pair being sessile and the other pedicellate. Because of the great crowding of the staminate spikelets, the arrange- ment may be obscured. The staminate spikelets are each two-flowered. Corn never persists after cultivation and is un- known in the wild state. It is suspected that it originated in Central America. Euchlaena mexicana Schrad. (TEOSINTE) is in- termediate between corn and Tripsacum in struc- ture. The staminate spikelets are borne in a termi- nal tassel, like those of com, and the general ap- pearance of the plants is like that of com. The pistillate spikelets are borne in single spikes of hardened joints, like those of Tripsacum. These spikes break up into 1-spikelet segments when ripe. They are hidden, however, in husks hke those of the com ear. Teosinte is sometimes cultivated as a forage plant in the South and occurs as a weed in the American tropics. It is closely related to com and hybridizes with it. 185 -X z - = 3 o- X - =~s — o V* - — •« ~ — ^ - = IV» — — — E- _ _ - o> — = — — — = ^ — — — — — 0» w - — — ~" — — = 0> - 1TTTTTTT i — — u - = 09 - _. — — — .^ = ifi — — mm — _: = _ - — o A - — — _ — - _^ — — ^ — — — - — — ^ — — 1\) — - Ui ~ M» - w ~ ~ - — — _^ — A 1 ^ — — = Oi — ~ o» - Figure 356 INDEX AND PICTURED-GLOSSARY Aegilops 85 cylindrica 85 triuncialis 85 Agropyron 87 cristatum 88 desertorum 88 pauciflorum 89 repens 88 smithii 87 spicatum 89 subsecundum 89 trachycaulum 89 Agrostideae 11, 19, 21, 102 Agrostis 1 1 6 alba 117 exarata 1 1 8 humilis 1 17 hyemalis 1 1 8 oregonensis 1 19 palustris 1 16 perennans 1 19 scabra 1 18 tenuis 1 16 variabilis 1 1 7 Aira 97 caryophyllea 97 Alkali cordgrass 136 Alkali grass 58 Alkali sacaton 128 Alopecurus 103 aequalis 104 pratensis 103 Alpine timothy 1 12 American beachgrass 112 Ammophila 1 1 2 breviligulata 112 Amphicorpum 164 muhlenbergianum 164 purshii 164 Andropogon 180 barbinodis 182 furcatus 181 gerardi 181 glomeratus 181 hallii 181 perforatus 182 provincialis 181 saccharoides 182 scoparius 180 virginicus 181 Andropogoneae 12, 20, 21, 176 Annual bluegrass 82 Annual ryegrass 86 Anthoxanthum 145 odoratum 145 APEX: the tip of a leaf. 4 Fig. 356 Aristida 26, 106 basiramea 106 var. curtissii 106 dichotoma 106 fendleriana 107 longiseta 107 oligantha 107 Arizona fescue 73, 74 Arrhenatherum 22, 96 eiatius 22, 96 Arundinaria 15 gigantea 15 tecta 15 Arundo 24 donax 24 Astoria bent 1 16 AURICLES: small pointed or rounded projections at the base of the blade, 4. Fig. 357 Figure 357 Avena 99 fatua 99 sotiva 99 Aveneae 10, 22, 95 AWN : a protruding midrib of a glume or lemma, form- ing a beard or bristle. Lat- eral nerves rarely produce awns. 6. Fig. 358 Figure 358 Figure 356 Axonopus 159 offinis 159 B Bambuseae 10, 15 Barley 90 Barnyord grass 156 Beckmannia 135 syzigachne 135 Bermuda grass 135 B»g bluestem 181 Big galleta 130 Black grama 142 BLADE: the elongated spreading portion of a grass leaf. 4 Fig. 359 Figure 359 Blepharoneuron 126 tricholepis 1 26 Blowout grass 28 Eluebunch fescue 74 Bluebunch wheatgrass S9 Blue grama 131, 143 Bluejoint 114 Bottlebrush 91 Bouteloua 141 barbata 143 curtipendula 141 eriopoda 142 gracilis 131, 143 hirsuta 142 Brachiaria 157 ciliatissima 157 ex*ensa 1 57 platyphylla 157 Brachyelytrum 1 19 erectum 1 1 9 var. septentrionale 119 BRACT: a modified leaf. Glumes, lemmas, prophylls, and paleas are bracts. 5 Fig. 360 C_i^^^>— Figure 360 Bristly foxtail Brizo 45 media 45 minor 45 15' 186 INDEX Bromus 59 anomalus 65 var. lanitipes 65 arvensis 64 brizaeformis 63 carinatus 60 catharticus 59 ciliatus 62 commutatus 65, 67 inermis 61 japonicus 64, 65 kalmii 66 latiglumis 63 mollis 66 pumpeilionus 61 purgans 62 f. glabriflorus 62 racemosus 67, 65 rigidus 69 rubens 67 secalinus 64, 65 sterilis 68 tectorum 68 vulgaris 61 Brookgrass 32 Broomcorn millet 173 Broomsedge 181 Browntop 1 16 Browntop millet 171 Buchloe 16, 131 dactyloides 16, 131 Buffalo gross 131 Bullgrass 124 Burro grass 26 Bush muhly 125 Calamagrostis 1 13 canadensis 1 14 inexpansa 1 14 rubescens 1 13 Calamovilfa 1 1 5 gigantea 115 longifolia 115 CALLUS: the hardened or sharpened lower end of a floret. 6 Fig. 361 Figure 361 Canada bluegrass 75 Canada wild rye 94 Canary grass 144 Cane 1 5 Carpet grass 159 Catabrosa 32 aquatica 32 Catchfly grass 146 Cenchrus 16, 149 pauciflorus 16, 149 tribuloides 149 Cheat 64 Chess 64 Chewings fescue 73 Chlorideoe 11, 19, 20, 21, 131 Chloris 139 gayona 140 petraea 139 verticil lata 141 virgata 140 Cinna 104 orundinacea 104 latifolia 104 CLEISTOGAMOUS: self-polli- nated within unopened buds or florets. 6 Cleistogamous spikelets 28, 99 Cieistogenes 99, 100 Cocklebur grass 129 Cogon grass 176 Coix 184 lacryma-jobi 184 Colorado grass 170 Cottontop 155 Crabgrass 158 Creeping bent 116 Creeping red fescue 73 Crested dogtail 26 Crested wheatgrass 88 Crinkle own 180 Ctenium 138 aromaticum 138 CULM: the flowering stem of grasses. 3 Cultivated oats 99 Curly mesquite grass 130 Cut gross 146 Cynodon 135 dactylon 135 Cynosurus 26 cristatus 26 Cyperaceae 2 Doctylis 44 glomerata 44 Dactyloctenium 134 aegyptium 134 Dallis grass 161 Donthonia 99 californica 99 compressa 1 00 intermedia 99 spicata 100 Darnel 86 DECUMBENT: said of stems which are somewhat creep- ing at the base. 3 Fig. 362 Deschampsia 96 caespitosa 96 flexuosa 96 Diorrhena 31 americana 31 Digitaria 157 filiformis 157 ischoemum 1 58 sanguinalis 158 DIOECIOUS: having the stominote and pistillate flowers on separate plants. Diplachne 133 DISARTICULATE: to break up at some definite point, determined by anatomy. 6 Fig. 363 Figure 363 Disarticulation 6 Distichlis 17, 25 spicata 25 stricta 17, 25 Dogtown grass 107 Dorsally compressed Downy brome 68 Dune sandbur 149 Figure 362 Echinochloc 156 crusgalli 156 pungens 156 walteri 156 Eleusine 134 indica 134 Elymus 92 canadensis 94 cinereus 93 condensotus 93 riporius 94 triticoides 92 villosus 93 virginicus 94 Emmer 87 Enneapogon 23 desvouxii 23 187 INDEX Eragrostis 32, 33 beyrichii 35 capillaris 40 Cilianensis 41 ciliaris 34 curvula 37, 38 frankii 40 glomerata 34 hirsuta 38 hypnoides 33 intermedia 39 megastachya 41 multicauiis 42 oxylepis 35 pectinacea 42 peregrina 42 pilosa 43 poaeoides 41 reptans 33 secundiflora 35 sessilispica 35 spectabilis 36 trichodes 37, 38 Ergot 86, 161 Erianthus 177 alopecuroides 177 contortus 177 giganteus 177 ravennae 178 sacchoroides 177 Eriochloa 155 contracta 155 Euchlaena 185 mexicana 185 Eulalia 176 FLORET: the unit of the spikelet, consisting of a flower and the iemnna and poiea which surround it. 5. Fig. 364 Foil Panicum 174 Fail witchgrass 163 False buffalo grass 131 Feather fingergrass 140 Festuca 70 arizonicQ 73 capillota 73 elotior 70 idahoensis 73, 74 kingii 71 obtusa 71 occidentalis 73 octoflora 70 ovina 74 var. brachyphylla 74 paradoxa 71 rubra 73 thurberi 72 viridula 72 Festuceae 10, 22, 23 Festucoideoe 10 Field sandbur 149 Goatgrass 85 Goosegrass 134 Gramineae 1, 2 Grasses 2 Green fescue 72 Green foxtail 153 Green sprangletop Gymnopogon 139 ambiguus 139 Figure 364 Flower clusters 4 Fluffgrass 29 Fluminea 46 festucacea 46 Fountain grass 150 Foxtail barley 90 Foxtail millet 152 Galleta grass 130 Gama grass 184 Gardeners Garters 144 Gastridium 1 13 ventricosum 113 Giant dropseed 128 Giant foxtail 153 Giant reed 24 Giant wild rye 93 GLUME: an empty bract at the base of a spikelet. 5 Fig. 365 Figure 365 Glyceria 52 acutiflora 52 borealis 53 canadensis 55 elata 56 fluitans 53 grandis 55 melicaria 54 obtusa 54 pallida 57 var. fernaldii 57 pauciflora 57 septentrionalis 53 striata 56 133 H Hackelochloa 178 granularis 178 Hair fescue 73 Hairgrass 96 Hairy grama 142 Hesperochloa 71 kingii 71 Heteropogon 1 79 contortus 179 melanocarpus 180 Hierochloe 145 odorata 145 Hilaria 130 belangeri 130, 131 jamesii 130 mutica 130 rigida 130 Holcus 19, 101 lanatus 19, 101 Holy grass 145 Hordeae 10, 21, 85 Hordeum 90 brachyantherum 91 jubatum 90, 92 leporinum 91 pusillum 91 vulgare 90 Hydrochloa 147 carol inensis 147 Hystrix 91 patula 91 var. bigeloviana 91 Imperata 176 brevifolia 176 cylindrica 176 Indian corn 185 Indian grass 182 Indian ricegrass 108 Inflorescence 4 Japanese brome 64 Job's tears 184 Johnson grass 183 Juncoceae 2 Junegrass 95 K KEEL: a sharp fold, resem- bling the keel of a boat. 6 Kentucky bluegrass 78 Knotgrass 160 Koeleria 95 cristate 95 188 INDEX Lacegrass 40 Laterally compressed 6 Leaves 4 Leersia 146 lenticularis 146 oryzoides 146 virginica 147 LEMMA: the outer bract of a floret, which encloses the flower. 5 Fig. 366 Figure 366 Leptochloa 132 dubia 133 fcscicularis 133 filiformis 132 Leptoloma 163 cognatum 163 LIGULE: a collar-like pro- jection at the base of a leaf blade, 4 Fig. 367 Figure 367 Little barley 91 Little bluestem 180 LODICULE: a small blister- like body at the base of the flower, which forces the floret open at the time of blooming. 5 Fig. 368 Lolium 86 perenne 86 var. italicum temulentum 86 Lycurus 102 phleoides 102 86 NODE: the usually swollen joint of a stem, at which a leaf is attached. 3 Fig. 369 M 172 70 103 51 49 Maiden cane Maize 185 Manisurus 179 rugosa 179 Mat muhly 121 Meadow fescue Meadow foxtail Melica 47 bulbosa 51 fugax 51 imperfecta mutica 48, nitens 49 porteri 48 var. laxa 48 smithii 49, 68 spectabilis 50 stricta 47 subulate 50 MIDRIB: the center "vein" Milium 105 effusum 105 Miscanthus 176 sinensis 176 Monocotyledons Mountain brome 60 Muhlenbergia 120 arenacea 121 asperifoiia 121 cusDidata 124 emersleyi 124 frondosa 122 glomerata 122 mexicana 123 montana 123 porteri 1 25 racemose 122 richardsonis 121 schreberi 120 sobolifera 122 squarrosa 121 sylvatica 123 torreyi 125 wrightii 124 Munroa 27, 131 squarrosa 27, Mutton grass 82 conspicuous of a leaf. 4 1 Figure 369 Oats 99 Oniongrass 50, 51 Orchard grass 44 Oryza 146 sativa 146 Oryzeae 11, 18, 146 Oryzopsis 108 asperifoiia 108 hymenoides 108 micrantha 109 miliacea 109 ractmosa 108 OVARY: the swollen lower portion of the pistil, which contains the seed. Fig. 370 131 N Figure 370 PALEA: the inner of the two bracts which enclose o grass flower. 5, 6 Fig. 371 Figure 368 Natal grass 154 Needle and thread 1 10 Needlegrass 106 NERVE: one of the vascular bundles of a leaf or other plant structure, also called a vein. 4, 6 New Zealand bent 1 16 Nimble Will 120 Nit grass 1 13 Nodding fescue 71 Nodding foxtail 152 Figure 371 189 INDEX Paniceae 12, 19, 149 PANICLE: a much-branched inflorescence, bearing spikelets on pedicels. 4 Pcnicoideae 12, 149 Ponicum 165 agrostoides 175 onceps 175 arizonicum 170 ashei 169 boscii 167 brachyonthum 170 copiilare 173 clandestinum 167 columbianum 169, 166 condensum 175 depauperatum 165 dichotomiflorum 174 dichotomum 168 fosciculatum 171 var. reticulatum 171 hemitomon 172 implicatum 166 latifolium 167 lindheimeri 165 meridionale 169 microcarpon 168 miliaceum 173 obtusum 171 polyanthes 168 rhizomatum 175 scoparium 166 scribnerianum 167 sphaerocarpon 168 texanum 170 verrucosum 170 virgatum 174 Pappophorum 23 wrightii 23 Pappus grass 23 Paspalum 159 debile 160 dilatatum 161 dissectum 159 distichum 160 floridanum 162 laeve 162 var. circulare 162 pubescens 161 setaceum 160 urvillei 161 Peanut grass 164 Pearl millet 150 PEDICEL: the stalk of a single spikelet. 5 Fig. 372 Figure 372 PEDUNCLE: the stalk inflorescence. 5 Pennisetum 20, 150 glaucum 150 ruppelii 150 setaceum 1 50 of an PETIOLE: a leaf stalk (ab- sent in most grasses ex- cept bamboos). Phalarideae 11, 22, 144 Phalaris 144 arundinacea 144 canariensis 144 Phleum 1 12 alpinum 1 1 2 pretense 1 1 2 Phragmites 24 communis 24 Pine dropseed 1 26 Pinegrass 73, 1 1 3 Pinyon ricegrass 1 1 1 Piptochaetium 1 1 1 fimbriatum 1 1 1 Plains bluegrass 76 Plains foxtail 154 Poa 75 alsodes 80 annua 82 arachnifera 17, 77 arida 76 autumnalis 81 compressa 75 cusickii 83 cuspidate 77 epilis 84 fendleriana 82 glaucifoiia 76 interior 79 macrantha 77 nervosa 76 nevadensis 83 palustris 79 pratensis 78 scabrella 81 sylvestris 80 trivialis 79 Polypogon 103 monspeliensis 103 Porcupine grass 109 Poverty oatgrass 100 Prairie cup grass 155 Prairie dropseed 127 Prince Edward Island bent 1 1 6 PROPHYLLUM: the mem- branous structure found between the main stem and the base of a branch. 3 Fig. 373 Puccinellia 58 a:roides 58 distans 58 fasciculata 58 nuttalliana 58 PULVINUS: a swelling at the bases of branches of an inflorescence. 5 Purple lovegrass 36 Purpletop 29 Quackgrass 88 Quaking grass 45 Rabbitfoot grass 103 RACEME: an unbranched in- florescence, bearing spike- lets on pedicels which are attached to the central axis. 5 Fig. 374 Figure 374 RACHILLA: the central stalk of a spikelet, which bears the florets. 5, Fig. 375 Figure 373 Proso millet 173 Pseudosasa 1 5 japonica 15 Figure 375 190 INDEX RACHIS: the central axis of an inflorescence, which bears branches or spike- lets. 5 Rattlesnake chess 63 Kottlesnake manna 55 Ravenna grass 178 Red fescue 73 Red sprangletop 132 Redfieldia 28 flexuosa 28 Redtop 1 17 Reed 24 Reed canary grass 144 Rescue gross 59 RHIZOME: a stem which grows beneath the surface of the ground. 3, Fig. 376 Sedge Family 2 Sedges 2 SESSILE: seated directly on the axis; lacking a pedi- cel. 6, Fig. 377 Figure 376 Rhode Island bent 1 16 Rhodes gross 140 Rhynchelytrum 154 roseum 1 54 Rice 146 Ringgross 125 Rip-aut gross 69 Roots 3 Rough stalk bluegross 79 Ruby gross 154 Rush Family 2 Rushes 2 Rye 86 Ryegrass 86 Socoton 129 Sacchorum 178 officinarum 178 Sacciolepis 163 striata 163 Sock gross 163 St. Augustine gross 149 Salt grass 25 Salt-marsh gross 136 Sand bluestem 181 Sand dropseed 1 28 Sand iovegross 37 Sand reedgross 1 1 5 Satintail 176 Schedonnordus 136 panicuiotus 136 Schizochne 46 purpuroscens 46 Scholochloa 46 festucoceo 46 Scleropogon 17, 26 brevifolius 17, 26 Scrotchgross 121 Sea oats 43 Secole 86 cereole 86 Figure 377 Setoria 151 foberii 152 genicuioto 151 glauca 151 italico 152 lutescens 151 mocrostochyo 1 54 magna 153 verticilioto 151 viridis 153 SHEATH: the tubular, usual- ly split portion of a grass leaf, which surrounds the stem. 4, Fig. 378 Sleepy grass 1 1 1 Slough grass 135, 137 Smilo gross 109 Smooth brome 61 Smooth crabgross 158 Sorghostrum 182 nutans 182 Sorghum 183 holepense 183 sudonense 183 vulgare 183 Southern wild rice 148 Spartina 136 olternifloro 137 cynosuroides 137 gracilis 136 patens 136 pectinoto 137 townsendii 137 Spelt 87 Sphenopholis 100 intermedia 100 nitido 100 obtusoto 100 SPIKE: on unbronched inflor- escence, with spikelets at- tached directly to the axis. The spikelets may be on one side or both sides of the rochis. 5, Fig. 379 Figure 378 Sheep fescue 74 Side-oots grama 141 Silver beordgross 182 Silver hoirgross 97 Silver plumegrass 177 Sitonion 92 hystrix 92 jubatum 92 Six-weeks fescue 70 Six-weeks grama 143 Six-weeks grasses 70, 143 Skyline bluegrass 84 Figure 379 Spike fescue 71 Spike muhly 124 Spike redtop 1 18 Spike Trisetum 98 SPIKELET: the smallest bronchlet of a gross inflor- escence, typically consis- ting of glumes, rachilla, and florets. 5 Spikelets 5 Sporobolus 126 oiroides 128 asper 1 27 clondestinus 127 cryptandrus 128 gigonteus 128 heterolepis 127 macer 1 27 neglectus 126 voginoeflorus 126 wrightii 129 Squirreltail 92 STAMEN: the pollen-produc- ing organ of a flower. 5 Stems 3 Stenotophrum 1 49 secundatum 149 191 INDEX STIGMA: the feathery appen- dages at the tip of the ovary, which receive pol- len. 6, Fig. 380 Figure 380 Stinkgrass 41 Stipa 109, 179, 180 comata 1 10 leucotricha 1 10 robusta 1 1 1 spartea 109 viridula 1 1 1 STOLON : a stem which creeps along the surface of the ground. 3, Fig. 381 Figure 381 Sudan grass 183 Sugar cane 178 Sweet vernal grass 145 Switch grass 174 Tall oatgrass 96 Tanglehead 179 Teosinte 185 Texas bluegrass 77 Texas millet 170 Texas needlegrass 110 Ticklegrass 118 Timothy 1 12 Tobosa grass 130 Toothache gross 138 Trochypogon 180 secundus 180 Tragus 16, 129 beteronionus 16, 129 Trichochne 155 californica 155 Trichloris 138 blonchardiona 138 crinita 138 mendocina 1 38 Tricholoena 1 54 rosea 1 54 Tr.dens 22, 29 albescens 30 chapmoni 29 elongotus 31 flovus 29 muticus 31 pilosus 30 pulchellus 2^ Triodia 29 albescens 30 flovo 29 mutica 31 pilosa 30 pulchella 29 Triplosis 28 omericona 28 purpurea 28 Tripsoceoe 13, 16, 17, 184 Tripsacum 184 doctyloides 184 Trisetum 97 interruptum 97 pennsylvanicum 97 spicotum 98 wolfii 98 Triticum 87 oestivum 87 Triviolis 79 Tumblegross 136 U Vasey grass 161 VEIN: one of the vascular bundles of a leaf or other plant structure, also call- ed a nerve. 4, 6 Velvet grass 101 Vine mesquite grass 171 Virginia wild rye 94 Vulpia 70 W 141 Water gross 147 Wedgegross 100 Weeping lovegrass 38 Western wheotgross 87 Wheat 87 White gross 147 Wild chess 66 Wild oats 99 Wild Rice 148 Windmill gross Wiregross 106 Witch qross 173 Wolftoil 102 Woodreed 104 Y Yellow foxtail 151 Zowodke alkali grass 58 Zea 185 mays 185 Zizonia 148 oquotica 148 Zizanieae 12, 17, 147 Zizaniopsis 148 miliocea 148 Zoysieoe 11, 20, 1 29 Uniola 43 lotifolia 44 poniculota 43 192 i ^ t^