ImfA A VEGETATIVE KEY TO THE GRASSES TEXAS OF ERATH COUNTY, THESIS. Presented to the Graduate Council of the. North Texas State College in Partial

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1 ImfA A VEGETATIVE KEY TO THE GRASSES OF ERATH COUNTY, TEXAS THESIS Presented to the Graduate Council of the North Texas State College in Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE By Inez Evans Robins on, B S Dublin, Texas August, 1951

2 * TABLE OF CONTETS Page INTRODUCTION a M ETHODS a " 0 5 USE OF THE KEY a 0 0 S 0 7 Mechanics Glossary KEY TO GJERA AND SPECIES CONCLUSIONS 0 0 " LITERATURE CITED 0 * APPENDIX Index of Scientific Names Cross Index of Common Names Index of Plates iii

3 A VEGETATIVE KEY TO THE GRASSES OF ERATH COUNTY, TEXAS INTRODUCTION At the present time, in contrast to an earlier agricultural period, stock farming and ranching are of primary economic importance in Erath County, Texas * The rough stony land with thin soils, which are described later in this chapter, are best fitted for grazing With this natural condition prevailing in the county and with considerable areas of deep productive soil to supplement the grazing possibilities, farmers have turned from row crops to ranching and dairying Because of this change in agricultural practices, many individuals of the county have evidenced an interest in native grasses and their identification This study is a result of such an interest Two extensive studies, including keys, have- been made by authorities of the grasses of Texas (Hitchcock 1935; Silveus 1933) In these floras identifications are based on floral morphology and not on vegetative characteristics Descriptions, ranges, and habitats of indigenous species are extensive and need no further amplification in this treatise However, since the phenology of grasses is seasonal, sometimes not occuring until the second year as in biennials, it is not 1

4 2 always possible to collect a specimen with a fully developed infloresence Hence, a key based on vegetative characters makes identification possible for grasses in all stages of growth To meet such a need this key was prepared for the grasses of West Central Texas As previously mentioned, the study area for this investigation was limited to Erath County, which is included in an agricultural area with approximately two-thirds of its 693,120 acres in native grass pastures (Bushnell 1923) A majority of the same grasses are found in the adjoining counties of Comanche, Eastland, Hood, and Sommerville Their floristic unity is evident from the distributional sequences of Cory (Cory and Parks 1937) in that the completed list of collected grasses includes most of the grasses of the west section of his plant areas 4 and 7 Erath County is located in the western section of plant area 4 and joins area 7 Erath County is situated slightly north of the center of Texas and about 80 miles southwest of Dallas (Fig 1) The coordinates of the county are t W longitude and t N latitude The enclosed land mass is irregular, is about 40 miles long by 30 miles wide, and has an area of approximately 1,083 square miles (Bushnell 1933), (Fig 2) The eastern section of Erath County is a part of the Grand Prairie This association is characterized by a discontinuous mosaic of small clumps of liveoaks and associated species grading into a mesquite tree and scattered scrub

5 3 savannah in the southern part The western portion is a part of the West Cross Timbers Structurally, the forest is dominated by postoak and blackjack oak to a lesser degree In the prairies coarse grasses predominate with grama grasses and short grasses in the lower synusiae In the southern area mesquite comes in as a ruderal subseral invader (Carter 1931) The county has a climate characteristic of the grasslands formation, even though forest communities exist because of secondary edaphic control That is, the average annual rainfall, determined by the records of the United States Weather Bureau at Dublin, Texas, is 2938 inches and the mean annual temperature is 6460 F The growing season consists of 239 days Physiographically, the southern two- thirds of the county consists of a smooth southwardly sloping plain, with a few flat-topped hills in the southeastern part of the county This smooth plain is bordered on its northern edge by a narrow belt of hilly country formed by a series of narrow valleys and terminated by an abrupt drop to a lower plain The rough belt including the abrupt drop is about three miles wide and runs east and west across the northern part of the county, turning southward along the eastern margin for several miles North of this rough belt is a parallel, smooth lowland strip three to five miles wide, which gradually rises northward and merges into a low hilly area occupying the extreme northern part of the county (Bushnell 1923)

6 4 The elevations in the central part of the county range from 1,200 feet to 1,500 feet The maximum altitude for the county is over 1,750 feet and the average elevation is 1,466 feet The soils of the county include the six soil series: San Saba, Denton, Crawford, Brackett, Bell, and Lewisville of the Grand Prairies region and Windthrost, Nimrod, and Milam of the Western Cross Timber region The San Saba soils are black or dark brown in color with very dark-gray clay subsoils These soils have the deepest profile The Denton and Crawford soils are shallower and the Brackett soils are very thin The soils of the Windthrost and Nimrod series are sandy, being very deep in some areas and thin in others These top soils contain little organic matter and are lighter in texture than the subsoils (Carter 1931)

7 METHODS The orientation of this study began with a collection of the grasses of Erath County during their flowering periods Collections were made in the spring and fall of 1950 and 1951 to obtain both vernal and autumnal grasses Identifications were made from the grass floras previously mentioned (Hitchcock 1935; Silveus 1933) and checked against specimens in the herbarium of North Texas State College for verification In addition, the list was checked by W* A Turney, Conservationist, United States Department of Agriculture of Dublin, Texas Finally, the list was compared with that prepared by W M Cory for the plant areas of which Erath County is a part (Cory and Parks 1937) On the basis of the above inder fications, a critical study of the vegetative characteristics was made and a key based on these features prepared The width of the blade and characteristics of the ligule, roots, culms, and sheaths were used to distinguish each of the eighty-six specimens found in the collection area A drawing was made of the longitudinal section of the juncture of the blade and the sheath of each grass This diagnostic section includes the collar, ligule, a part of the blade and sheath, and auricles, if present 5

8 6 A glossary of special terms was prepared from the descriptions made in the key to facilitate its use And in addition an index was made of the scientific designations together with a cross index of common names recognized by Hitchcock, Silveus, and Cory

9 USE OF THE KEY Mechanics The key prepared is of a dichotomus nature, The pairs of contrasting characters lead one to an ultimate decision of the entity in that only one of the two designations is correct For example, if a collected plant is either grass or grasslike, as might be the case of a sedge or rush, a determination is made first from Oa and Ob If it is found from Oa that the plant is a grass one proceeds, then, to la and lb, a pair ofcharacters which separates all grasses into annuals and perennials If it is the former, one proceeds to 2a and 2b Next, pubescence of the leaf and sheath must be determined Should one find both parts pubescent one follows through to number 13 and investigates the culm node, and if glabrous, continues to number 14a Then if the ligule is ciliate and the blades 7-16mm wide, the plant is Panicum texanum Otherwise 14b, with ligule membranaceous and entire, and blades 2-7mm wide, would identify the grass as Chloris vata A further check may be made by comparing the specimen with the drawings of the two above species, either Fig 25 or Fig 26 of Plate VI Glossary The glossary of terms which follows will aid in the use of the descriptions found in the key Acuminate--graduAlly tapering to a sharp point, more tapered than acute (Fig 13) 7

10 8 Acute--tapered rather evenly to a point Annual--living but one year Annual grasses have neither dead culms nor leaves of the previous year's growth at the base Antrorse--directed upward and forward Opposed to retrorse Apex--tip of the blade, sheath, ligule, or culm Appressed--lying against an organ or part Aristate--awned, provided with a bristle at the end Attentuate--tapering into a long slender point Auricle--having ear-like appendages or projections at the juncture of the base of the blade and the sheath Blade--the expanded part of the leaf above the sheath Bulbous--enlarged and fleshy, bulb-like in shape or structure (Fig 4) Canescent--gray-pubescent or hairy Cartilaginous--gristly, hard and tough but elastic Ciliate--fringed with hairs on the margin (Fig 7) Collar--the region on the outside of the grass leaf which marks the juncture of sheath and blade (Fig 10b) Conduplicate--folded together lengthwise with upper surface within Coriaceous--leathery in texture Culm--the stem of the grass; often restricted to the true stem above the ground and to distinguish it from rhizomes and stolons which are modified stems (Fig 3) Decumbent--more or less reclining or spreading along the ground

11 9 Decurrent--extending down an organ below the insertion; especially used concerning ligules decurrent on the margins of the sheath Depauperate--reduced or undeveloped, plants below the average size Erose--irregular notched at apex as if gnawed (Figs 7 and 8) Finbricate--fringed, the hairs longer or coarser than the ciliate condition, finer than laciniate Flexuous--bending in opposite directions Glabrous--devoid of hairs; smooth in the sense of absence of all hairiness Glaucous--covered with a waxy coating that gives a blue-green color as in the leaf of a cabbage Hirsute--With short, straight, fairly stiff hairs Hispid--bristly; beset with stiff, rough, bristle-like hairs Hispidulous--minutely hispid Imbricate--overlapping Internode--the part of a stem between two successive nodes Involute--inrolled, that is, with both edges rolled in toward the center, as a grass blade, each edge presenting a spiral appearance in cross section (Fig 10b) Keel--projecting ridge on a surface as the keel of a boat (Fig 9) Knotted--with enlargements along the root stock Lacerate--irregular, as though frayed out by being cut or torn Lanate--covered with soft tangled long hairs

12 10 Lanceolate--rather narrow tapering to both ends, the broadest part below the middle; lance shaped Lanciniate--narrowly incised or slashed Ligule--the thin appendage on the side of a leaf at the junction of sheath and blade (Figs 3, 6, 13, and 15) Membranous --membrane-like Mm--millimeter; about 1/25 of an inch Navicular--boat shaped; shaped like the bow of a canoe Nerve--the vascular veins of the blades, glumes, and lemmas approximately parallel Node--the joint of the culm; swollen and joint-like portion of the stem (Fig 3) Ovate--egg-shaped in longitudinal section, broadest below the middle Papillose--bearing minute nkpple-shaped projections Papillose-hispid--bearing hairs with bases that are slightly swollen and somewhat nipple-shaped Perennial--lasting more than one year; applied to grasses in which the underground parts last more than one year; and to woody culms to distinguish them from those which die to the ground even though the undergrounds are perennial Pilose--pubescent with soft, straight hairs Puberulent--with very short, soft hairs Pubescent--in a general sense, and as used here, with hairs Pustulate--blistery, furnished with pustules or irregular raised pimples

13 11 Retrose--turned backward or downward Revolute--rolled back from margin of the apex Rhizome--an underground stem; rootstock; recognizable by the scale-like leaves at regular intervals (Fig 4) Rigid--stiff and firm Rootstock--rhizomes (Fig 4) Scabrous--rough to the touch, like sandpaper, due to scalelike projections from the surface Scaly--wi th minute scales on the surface Scarious--thin, dry, membranaceous, not green Sericeous--velvety Setaceous--bristle-like Sheath--the lower part of a leaf which usually enfolds the stem (Figs 3, 15, and 16) Stolon--a trailing or reclining stem, above ground, which strikes roots where the joints touch the ground, there sending up new shoots and new plants (Fig 11) Striate--marked with slender, longitudinal grooves; minutely channeled Sulcate--grooved longitudinally Truncate--square tipped, as though chopped off Villous--with long, soft hairs

14 IEY TO GENERAL AND SPECIES a, "tens (Gulms, see Fig 1) hollow, sometimes solid; cylindrical, flattened, not triangular; nodes conspicuous; leaves two-ranked (1) Ob Stems, leaves, and nodes not as above $edges, 0 rushes, and other grass-like plants st;op la Plants lb Plants annual perennial 2) a5) 2a Blades 2b Blades 2c Either and sheaths pubescent and sheaths glabrous blades or sheaths glabrous (2L3) (3) (6) 3a Blades 3b Blades 4a Ligule 4b Ligule 5a Ligule navicular Poa annua (Fig 17) not as above membranaceous, margins fringed Chloris verticillata (Fig 18) membranaceous, margins entire very thin 4mm long Phalaris canariensis (Fig 19) (4) (5) 5b Ligule very short 06mm long, somewhat erose-ciliate sometimess lower sheath pubescent) Pestuca octoflora (Fig 20) 6a, Blades glabrous; sheaths pubescent (at least lower sheaths as in Horde-2 pusillum sometimes glabrous as in Eleusine indica) 12 (7)

15 13 6b Blades pubescent; sheaths glabrous (11) 7a LoWer sheaths pubescent; upper sheaths scabrous Hordeum pusillum (Fig 21) 7b Lower sheaths glabrous,; upper sheaths pubescent, papillose at margins Eleusine indica (Fig 22) 7c Lower and upper sheaths pubescent (8) 8a Blades 5-10m wide; sometimes 15mm wide Setariafviridis (Fig 23) 8b Blades 6mm wide or less (9) 9a Blades 2mm wide or less Eragrostis piosa (Fig 24) 9b Blades 2-6mm wide (10) 10a Ligule membranaceous, fringed Limnodea arkansana (Fig 25) 10b Ligule a ring of hairs Eragrostis cilianensis (Fig 26) h1a Culms decumbent, flattened; ligules ciliate (upper sheaths pubescent on margin) Cenchrus echinatus (Fig 27) 11b Culms erect (12) 12a Blades 1-2mm wide; nodes slender Aristida oliganth (Fig 28) 12b Blades 2-7mm wide; nodes swollen Bromus secalinus (Fig 29) 13a Nodes glabrous (14) 13b Nodes pubescent (15) -1-4-

16 14 14a Ligule ciliate; blades 7-6mn wide Panicum texanum (Fig 30) 14b Ligule membranaceous, entire blades 2-7Im, wide Chloris virgata (Fig 31) I5a Ligule a ring of hairs (16) 15b Ligule membranaceous or partly so (is) 16a Blades more than 4mm wide, Panicum fasciculatum (Fig 32) 16b Blades less than 4mm wide (17) 17a Blades roagh ciliate towards base sometimes papillose-ciliate Triplasis purpurea (Fig 33) 17b Blades glabrous or sparingly pilose Eragrostis cafllaris QFig 34) 18a Ligule barely pubescent porbolus neglectus (Fig 35) 18b Ligule entirely glabrous (19) 19a Nodes sparsely pilose, hairs retrose Bromus mollis (Fig 36) 19b Nodes distinctly pubescent * (20) 20a Sheaths as long as or longer than the internode (21) 20b Sheaths shorter than the internode (22) 21a Ligule ciliate Pauicuo capillare (Fig 37) 21b Ligule toothed or erose Bromus secalinus (Fig 29)

17 15 22a heaths green (23) 22b Sheaths canescent, sericeous Bromus aponicus (Fig 36) 23a Sheaths open * * Digtaria sa nl (Fig 38) 23b Sheaths closed (24) 24a Sheaths usually retorsely pilose; sheaths and blades strongly nerved Bromus comutatus (Fig 36) 24b Sheaths and blades not as above Bromus catharticus (Fig 39) 25a Stolons present (26) 25b Stolons absent (29) 26a 'tolons 7ith swollen nodes Panicum obtusum (Fig 40) 26b Stolons with slender nodes (27) 27a Leaves rigid modon dacylon (Fig 41) 27b Leaves curly (28) 28a Nodes glabrous; internodes short Buchloe dactyloides (Fig 42) 28b Nodes villous Hilaria Belangeri (Fig 43) 29a Rhizomes present (30) 29b Rhizomes absent (45) 30a Rootstock scales well developed (31)

18 16 30b Rootstock scales depauperate (33) 31a Sheath hairs papillose (32) 31b Sheath hairs neither pustilose nor papillose Panicum virgtum (Fig 44) 32a Ligule very short, ciliate-fringed Bouteloua curtipendula (Fig 45) 32b Ligule a ring of short fine hairs Boutelous uniflora (Fig 46) 33a Rootstocks long and creeping (34) 33b Rootstocks short (36) 34a Lower section of culm and rootstock canescent or pale; auricles present Agropyron Smithii (Fig 47) 34b Culm and rootstock not canescent (35) 35a Ligule membranaceous, about 1mm long, ovate; leaf tip navicular Poa arachnifera (Fig 48) 35b Ligule 3-4mm long, villous just back of ligule Andropogon Hallii (Fig 49) 35c Ligule membranaceous, ciliate, 2-3mm long Sohum alepense (Fig 50) 36a Sheaths longer than the internode (37) 36b Sheaths shorter than the internode (38) 37a Leaves involute toward apex Panicum Reverchoni (Fig 51)

19 17 37b Leaves flat at apex * * * * Uniola la(fig 52) 38a Rhizome narrow; internodes long; barbed at nodes, otherwise glabrous Leersia oryzoides (Fig 53) 38b Rhizome stout * (9) 39a Culms glaucous or purplish; sheaths glaucous Andrpgon Drovincialis (Fig 54) 39b Culms and sheaths neither glaucous nor purplish (40) 40a Rootstock knotted (41) 40b Rootstock not knotted (42) 41a *Nodes swollen, usually dark; blade midribs large Paspalum dilatatum (Fig 55) 41b Sheaths imbricate; sheath and blade glabrous Melica mutica (Fig 56) 42a Ligule membranaceous, short (43) 42b Ligule 2-5mra long - (44) 43a Blades lanceolate tapering to the end; ligule truncate fringed with short hairs Uniola latifolia (Fig 57) 43b Blades involute; ligule membranaceous * Manisuris cylindrica (Fig 58) 44a Ligule ciliate Soru h4halepnse (Fig 50) 44b Ligule lacerate + * * a A2ros2tis alba (Fig 59)

20 18 45a Blades and sheaths pubescent (61) 45b Blades and sheaths glabrous (53) 45c Either blades or sheaths pubescent (46) 46a Sheaths glabrous; blades with few scattered long hairs Erajrostis sessilisica (Fig 60) 46b Blades glabrous; sheaths pubescent (47) 47a, Sheaths longer than internodes (48) 47b Sheaths, at least lower, shorter than internodes (50) 48a Culm base bulbous; ligule a ring of short hairs E raostis curtipedicellata (Fig61) 48b Culm base not bulbous; ligule minutely ciliate, not over 05mm long (49) 49a Blades involute, curved, or flexuous; sheaths sparsely villous at throat Aristida glauca (Fig 62) 49b Blades involute drying flat; sheaths rough, villous at throat Aristida purpurea (Fig 63) 50a Ligule a ring of short hairs (51) 50b Ligule membranaceous (52) Sla Upper sheaths longer than internodes inclosing base of panicle; blades accuminate, margin long ciliate s (Fg Sporobolus cryptandrus (Fig 64)

21 19 51b Blades flat soon becoming involute to apex with long narrow tip; tuf ts of hair at throat Erarostis secundiflora (Fig 65) 52a Ligule short membranaceous, truncate; blades 6-8m wide flat, auricled JElymus irginicus (Fig 66) 52b Ligule very short membranaceous, ciliate, cilia 3-6mm long; blades 2-5mm wide, long attentuate Chloris Ea yana (Fig 67 ) 53a* Tip of plant turning scythe-shaped to ground; ligule decurrent down margins Schedonnardus paniculatus (Fig 68) 53b Not as above - (54) 54a Sheaths, as long as, or longer than internodes (55) 54b Sheaths shorter than internodes (57) 55a Blades 6-8mm wide, flat * (56) 55b Blades 2mm wide or less; ligules membranaceous, 4-6mm long, fragile* - * Muhlenbr Reverchoni (Fig 69) 56a Collar auriculate Lolium multiflorum (Vig 70) 56b Collar continuous; ligule truncate E u canadensis (Fig 71) 57a Ligule a dense ring of hairs T~rdia calbesens (Fig 72)

22 57b Ligule membranaceous or wanting (58) 58a Sheaths striate; ligule very short with a few cilia 0 * * - Bouteloua gracilis (Fig 73) 58b Sheaths non-striate (59) 59a Blades aristate Chloris cucullata (Fig 74) 59b Blades not aristate * (60) 60a Ligule 3-4mm long Qryzopsis hymenoides (Fig; 75) 60b Ligule 1-2mr long Andro2poon saccharoides (Fig 76) 61a Culm with dark (contrasting) nodes Bouteloua rigidiseta (Fig 78) 61b Culm nodes of same coloration as internode (mostly light color except in Paspalum ciliatfolium and Framrostis lugens where node and internode are dark * (62) 62a Sheaths, as long as, or longer than internodes (63) 62b Sheaths, at least upper, shorter than internode (69) 63a Sheath nerves prominent; blades rounded and ciliate at base, acuminate Panicum Scribnerianum (Fig 79) 63b Sheaths nerves not prominent (64) 64a Ligule merbranaceous, long, fringed at apex Trichachne californica (Fig 80)

23 64b Ligules less than 4mm long or a ring of hairs (65) 65a Ligule a ring of hairs (66) 65b Ligule membranaceous, at least partly so (68) 66a Blades 2mm wide or less involute, setaceous Sporobolus heterolepsis (Fig 81) 66b Blades expanded, setaceous (67) 67a Ligule 2-4mm long; blades not attentuate Eragrostis pectabilis (Fig 82) 67b Ligule of short hairs; blades attentuate Eragotis trichodes (Fig 83) 68a Blades 7mm wide; ligule membranaceous, truncate, fimbriate - ***** l 1 dropogon glomeratus (Fig 84) 68b Blades 2-6mm wide, glaucous; ligule about 15mm long, a short membrane with hairs at least 1mm long, Panicum Hallii (Fig 85) 69a Blades strongly ciliate along a cartilagenous margin, ligule commonly produced into an auricle Paspalum ciliatifolium (Fig 86) 69b Blades with ligule not as above (70) 70a Sheath striate a * Eriochloa sericea (Fig 87) 70b Sheaths not striate (71) 71a Ligule 2-4mm long, thick and stiff; blades flat above, conduplicate below

24 Soraghastr nuans (Fig 88) 71b Ligule thin; blades flat below 72a Ligule a short dense ring of hairs 72b Ligule membranaceous (72) (73) (76) 73a Ligule hairs varying in length; nodes and internodes tinged with purple Eragrostis lumens (Fig 89) 73b Ligule hairs uniform in length (74) 74a Blades scabrous on margins Triodia flava (Fig 90) 74b, Blades not scabrous on margins, (75) 75a Culms striate; blades sparsely papillose-hispid on margin Bouteloua hirsuta (Fig 91) 75b Culms not striate; blades smooth along the margins, with few hairs on upper surface near the base Eragrostis Beyrichii (Fig 92) 76a Ligule densely ciliate-villous; ciliate on margin Setaria macrostachya (Fig 93) 76b Ligule short ciliate or glabrous (77) 77a Ligule 2-4mm long; truncate Andropogon perf oratus (Fig 94) 77b Ligule less than 2mm long (78) 78a Ligule rounded, short ciliate AndropogZ~on inicus (Fig 95) 78b Ligule tot rounded (79)

25 23 79a Ligule truncate (80) 79b Ligule of membranaceous lines, minutely ciliate Sporobolus pilosus(fig 96) porobolus asp er(fig 96) 80a Culms solid * (81) 80b Culms hollow (82) Sla Culms green or purplish; rarely glaucous; sheaths flattened, rare conspicuously villous Andropogon sparius (Fig 97) 81b Culms glaucous; blades becoming revolute; sheaths villous Andropogn t2rnarius (Fig 98) 82a Blades scabrous, white and often repand; culms lanate at base LUtoloma cogntum (Fig 99) 82b Culm nodes pubescent; blades scabrous on upper surface, hispidulous underneath Stpa leucotricha (Fig 100)

26 CONCLUSIONS The purpose of this paper was to prepare a simplified key based on vegetative characteristics, by which the grasses of Erath County, Texas, might be identified It was found that no such key was available and it was evident that due to the seasonal florescence of grasses, a key based on floral morphology was not sufficient The results of the study show that there are at least eighty-six grasses native to Erath County In addition, these grasses are generally prevalent in the area including the surrounding counties Vegetative taxa are distinctive and their systematic mechanics delineate in such a manner that any typical entity may be easily identified from the others Such taxa include the point of blade and sheath divergence, ligule variation, width of the blade, characteristics of the root system, and the nature of the culms, and were used to distinguish the species While this study includes only a small area, it is evident that similar keys could be prepared for other regions and groups of angiospernts 24

27 LITERATURE CITED Bushnell, T M, Soil Survey of Texas, Washington, Government Printin7ffice, l9 73J Carter, W J, Soils of Texas, Bulletin No 431, Texas Agricultural Experiment-tation, 1931 Cory, V L, and Parks, H B, Catalg e of' the Flora of the State of Texas, Bulletin No 550, Gl lege Station, Texas,T andm College, 1937 Hitchcock, A S, Manual of' the Grasses of' the United States, Washington, Government Printing Office, 1935 Hitchcock, C Leo, A Key to the Grasses of Montana, St Lotis, John S Swift Company, fl36 Silveus, W A, Texas Grasses, San Antonio, Texas, The Clegg Company, 1933 Tharp, Benjamin C a, the Vegtation of Texas, Houston, The Anson Jones Press,

28 APPENDIX INDEX OF SCIENTIFIC NA'iES Scientific Name Common Name Key No Fig No Agropron Smithii Western wheatgrass 34a 47 Agros tis alba Red top 44a 59 Andropogon elomeratus * Bushy beard-grass Hall 's beard-grass Hallii perforatus lrovincialis Big bluestem saccharoides 0 Silver beard-grass sco ius, Little bluestem ternarius virginicus Slivery beard-grass Broom sedge 68a * 35b 77a * 39a 60b 81a 81b 78a 0 " * 76 * Aristida glauca * Reverchon three-awn 49a * 62 oligantha purpurea Few-flowered aristida Purple needle grass 12a 49b 0 " Bouteloua curtipendula * Side-oats grama, 32a 0 45 * Blue grama 0 58a* 73

29 27a 27 Scientific Name Common Name Key No Fig No hirsuta Hairy grama 75a " 91 r igildi s eta Texas grama 61a 78 uniflora * Mesquite grass 32b S 46 Bromus catharticus * Rescue grass 24b 38 comautatus Hairy chess * 24a " " " 38 jaonicus Japanese chess 22b 38 mollis Soft chess " " 19a 38 secalinus, chess 12b 29 Buchloe dactyloides * Buffalo grass " 28a 42 oenchrus echinatus Southern sandbar " ila 27 Chloris cucullata * " 59a 74 gaysna Rhodes grass 52b 67 verticillata Windmill grass * 4a 18 virta Feather fingergrass 14b - yndon dactylon Bermuda grass 41 Diitaria sanuinal Echinochloa Crusgalli Crab grass Barnyard grass 23a * c * 79

30 Scientific Name Common Name Key No Fig No Eleusine indica **oosegrass 9 7b * 22 E ymus canadensis Wild rye 56b 71 virgini Cus * Virginia wild rye 9 52a 66 Eragrostis Beyrichi Love grass 75b 9 92 Cazi laris cilianenis * 10b 26 * Lace grass 17b, * 34 curtipedicellata Short stalked grass love 0 9 " 48b * 61 lugens ilosa " 9 73a -89 * Indian love grass " 0 9a 24 secundiflora Clustered love grass 51b 65 sessilispica Love grass 46a spectabilis Purple love grass 67a, 82 trichodes Love grass 67b 83 Eriochloa sericea Texas cup-grass 70a 87 Festuca octoflora * Six weeks fescue * 5b * 20 Hilaria Belangeri * Curly mesquite grass 28b, 43 Hordeu= * * Little barley * * 9 7a 21

31 0 Scientif ic Name Corson Name Key No Fig No Leersia oryzoides ~Pice cutgrass Leptoloma cognatuim * Fall witchgrass 38a a 99 Limodea arkansana Lolium multiflorum Italian rye grass 65a 70 Manisuris fylinrica Pitted jointgrass Melica mutica Two flower melic* 43b 41b duhlenberia Reverchoni b 69 Oryzsis hmenoides Indian mountain rice 60a 75 Panicum capillare Vitch grass 21a 37 fasciculatum Brown top millet 0 16a 32 Haallii HallAs panicum 68b 85 obtusum Vine mesquite grass 26a 40 Scribnerianum * 63a 79 Reverchoni 37a 0 51 texanum Texas millet; Colorado grass 14a 0

32 Sa * 30 ScientifiQ Iame virtatm, Common Name - Switch grass * Key No Fig No 1b 44 Papalum ciliatif olium dilatatum * * S * * * 0 * 6 9 * 41a * 86 a 55 Phalaris canariensis * Poa annua,arachnifera Annual bluegrass 0 Texas bluegrass 3a 35a Schedonnardus paniculatus * Tumble grass 53a 68 Setaria macrostachya viridis Plains brittle grass * Green brittle grass 76a 8a Sor hastrum nutans 0 0 * Indian grass 71a 88 Sorghum halepense Johnson grass 44a 50 jporobolus as p2r cryptandrus heter2lapsis neleftus pia22u3 0 * * Long-leaved rush grass * Sand dropseed * - Small rush grass b 51a * 0 66a 18a 79b

33 0 Scientific Name Common Name Key No Fig No S tipa leucotricha Texas needlegrass 82b 100 Tri cha chne californica Cotton top 64a 80 Triodia albescens S * * - 57a 72 flava * Purple top a " 90 Trpflasis purpurea * Sandgrass 17a * 33 Uniola latifolia laxa * Broadleaf uniola Slender spike-grass 43a 37b * " CROSS INDEX OF COIvL ON NAMES Common Name Annual bluegras s S cientific Name *oannua Barnyard grass * * * Echinochloa Crusgali Berrmuda grass Big bluestem S QCyodon dacttlon 2ndrop n 2provincialis Blue grams Broadleaf uniola Uniola latifolia Broom-sedge Brown top mille Buffalo grass Bouteloua gra cilis * * * Andropogon virinicup S4 * canicum fasciculatum Buchloe dactyloides Bushy beard&)gra ss Androp nglomeratus

34 32 Common Name Canary grass Chess Clustered love grass Cotton top Crab grass Curly mesquite grass Dallis grass Scientific Name Phalaris canariensis Bromus secalinus S rarostis secundiflora Trichachne californica Digitaria sanuinalis Hilaria BelalnerI Paspalum dilatatum Fall witchgrass Leptoloma cognatum Feather fingergrass Few-flowered aristida Fringed chloris Goosegrass Green bristlegrass Hairy chess Hairygrama Hall's beardgrass HallIs panicum Hedgehog grass Indian love grass Indian grass Indian mountain grass Italian rye grass Japanese chess Chloris virata Aristida oligantha Chloris cucullata * Eleusine indica Setaria viridis Bromus commutatus Bouteloua hirsuta AndropogonHallii S 4anic Hallii Cenchrus echinatus Eagrostis pilosa S orhstrum nutans Oryzopsis hymenoidea Lolium multiflorum Bromus japonicus Johns on grass* * Jh Sorghum halep ens e

35 Eraorostis Comrmon Name Lace grass Scientif ic Name illaris Little barley Hordeum Pusillum Little bluestem Andropogon scoparius Long-leaved rush-grass orobolus asper Love grass Eragrostis Beyrichii Mesquite grass Boutelous uniflora Pitted joint grass antsuris yndrica Setariamacrostayeha Plains briotlegrass B Purple needlegrass Aristida purpurea Purple top Triodia flava Purple love-grass ragros tisspectabilis Red top Agrostis alba Reverchon three-awn Aristida glauca Rescue grass Bromus catharticus Rhodes grass Chloris gaya Rice cutgrass Leersia ozoides Sand dropseed Sorobolus cryptandrus Sand grass Trilasis pururea Short-stalked love grass Eragrostis curtiedicellata Side-oats grama Boutelous curtipendula Silver beardegrass Andropogon sacharoides Silvery beard-grass Andropoon ternarius Six weeks fescue Festuca octoflora Slender spike-grass Uniola laxa Small rush-grass orobolus neglectus

36 34 Common Na me Soft chess Scientific Name - Bromus mollis Switchgrass SPanicum viratum Texas Texas bluegrass cup-grass Texas grama -- Panicum texanum Texas millet Texas needlegrass Tumblegrass Two-flowered melile elica ntica Vine mesquite gre ss Virginia wild ry Western wheatgra Wild rye Windmill grass XWitchgrass Poa richnif era Eriochloa sericea Bouteloua rigidiseta S Plate I Figure 1 Map of Texas showing Erath County (--after Tharp), Erath County indicated by shaded lines Plate II 2 Map of Erath County showing general surface features Stipa leuchotricha Schedonnardus paniculatus Panicum obtusum Evirginicus ss gropyron Smithii, Elxmus canadensis Chloris verticillata -Panicumcapillare IND2X OF PLATES Plate III Figure 3 Culm and leaf of grass 4 Roots, rhizomes, and base of culms 5 Leaves, ligule 6 Collar 7 Pubescent bla de and sheath 8 Ligule wanting 9 Keel 10 Involute blade 11 Stolon, node, and innovation

37 35 Figure 12 Erose ligule 13 Acuminate ligule 14 Ligule consisting of ring of hairs 15 Ligule united in tube 16 Closed sheath I 394 I 40 INDEX OF PLATES--Continued Plate IV Poa annua xio Chbloris vertiojllata X91 Pharlis canarienis x4 Festuca o oiax20 Hordeum pusillum x15 Eleusine indica x3 Setaria!viridi5 x6 rgrostis pilosa x20 Limnodea arkansana x6 Eraros tis cilianen &"* Cenchrus chinatus x3 Aristida oligantha xiq Plate V Bromus secalinus x7 Panicum texanum x3 Chloris virgata x3 Tanicum as caculatumu x2 Triplasis~j2p Era r10 re2a x5 os tis cparis x10 snglectus x20 Bromus mollis x6 japonicus x6 conmutatus x6 Pani~ ~~caup11are x3 Digitaria sanguinais x3- Bromus catharticus x3 PanicumWobtusumx5 Plate VI S 414 rynidon dactylon x6 S 42, 4 -Buoqh7loe daf:i6idesx anicum virga-tum x4 45 S Bouteloua curtipendula x5 S 46 Bouteloua untiflora x8 47 Asron Srithii x5 48 Tg ia chniea x5 49 7ndropogon Halmlii x Sor ghum halepense x2 Uanicum evh Uniola laxa x6 Plate VII 53 Leersia Dryzoides x12 54 AndroogniproIncialis x3 55 Faspalum dilatatum x2 56 Melica u ticax4 57 Uniola t~ifolia xl5 58 Maniuriscylindrica x6 59 Agrostis alba x5 60 Eragrostis aessilispisa x10 61 Eragrostis curtipedic- &llata x5 62 Aristida glauca x1l 63 AristId purpurea x10 64 tsporobolus crpndrus x6 Plate VIII 65 Eragrotis secundiflora x5 66 lymus virginicus x3 67 Chloris gayana x chedonnardus Panicula tus R10 69 ]Vluhlenbergia Reverchoni x12 70 Lolium multiflorum x4 71 Elymus canadensis x2 72 Triodia albescens x4 73 Bouteloua gra cilis x11 74 Chloris cucullata x10 75 oides x15 76 Andropogon sacchoroides x3 Plate IX 77 Echinochloa Cru alli x6 78 Sou te91olia r~ ~x 79 Panicum worlbnerianum x3 80 Tri'hachne calif ornica x6i pobou heterolei x20 82 Eragrostis spectabilis x5

38 36 INDEX OF PLATES---Continued Plate IX--_con Figure 83 Eragrostis trichodes x4 84 Andro o on iomeratus x5 85 Tn Cum1l18 86 uciliatifoliu x3 87 Eriochloa sericea x6 88 orattrum nutans x2 Plate X 89 Erarostis lugens x12 90 Trioda flava x3 91 BouteloiThirsuta x12 92 jrgr osi Brih 4 93 $etaria macros 'Iah x6 94 perforatusx4ndropogon 95* ndrop0on n icu0 x6 96 Sporobolus pilosus x6 97 dropogon scoparius x9 98 AndropOg n ternarius X9 99 Leptolomacoiatum X paleucotrica X4

39 I Pate 1 Long-leaf pine 2 Coastal prairie Z Feyette prairie 4 Mesquite---ohaparrrl 5 Coastal sand dunes 6 Granitic Boll with oak and mesquite 7 Edwards Plateau, oak---ceder 8 Mountains: Gaudalupe, Davis, Glas, Crthedral, Chensti, Chiaos 9 Live-oak, mesquite and Acacia on short grase 10 Trans-Peco@:Sotnl lechuguilla 11 Sandy south plains 12 High plains 13 Mesquite---grassland 14 Western cross timbers, oak---hickory Figl 15 Eastern cross timbers, oak---hickory 16 Oak---hickory 17 Loblolly pine, short-leaf Dine and oak---hickory 18 Black land prairie -- after Benjamine CTharp

40 38 Plate xi OMorla r1811 oill Sicnrha vo Il Ch1kkrml ubin \ MIL ES Fig2 ERATH C COUNTY

41 0p culm Platein I" "blade sheath leaves ro dled folded blade - - ligule auricles shesth throat of heath leaf \ rhizome ligule coll r bulbous - based roots stem 6 4 node -Ulm ligule wanting collar - K -- bl-desee - -E u Oe sce,t 7 keel (jnvoiute - pubescentj --- o-hineovation olrr reduced leaves internode ligule rose sheath -- - glabrous node S - sheath 4 bbvo closed ligule acurinte \ ( < \ /I, (united, forming tube) ligule- -- open) (consisting of -- besl membranoe portion cnd terminal fringeof hair) 1o T1 ebet lb --after LH/tohcock

42 17 40 Plae -IV AZ ~ 4-1

43 / 41 PILtev 1 H tui II 1 t I l '\ \\ 1 1' N // ~3j \N 1 T)9 1 /v? NI\ ~ ~ ~ ~\I it' 36 I 39

44 Iote vi I Ii I42 I, I, J' 47 51'

45 43 Plate-vjn 5-1 I if I 1\t1 4I t l7 6c --! Tj 771, 62

46 / / 44 P/caie vill '1 I' -to A 1 I 'IA 70 fi N \\ ~II~ 7T 1 \ I A? I' fl Ii r IfI,I /1 75

47 - / 45 PIOtex I ff1 j,,, \ \ \ 77 \~tji~ II 'Ii i II) 8? 'f~/f1t/ I 1'~ I\ / 't ~ // II, I~~1 87

48 / 46 PiQtex V,i ~ ~ V ~ / 1' 4"~ ~ ' ~: k j \>~ ~// YK~ ~ 4 ~ K 9-0 N (1 100