154 FLORA. 



awned, the awn rarely as long as the body. Lab. to Br. Col. and Alaska, south 

 to the mountains of N. E., N. Y., Penn. and Neb., and in the Rocky Mts. to 

 Colo. Ascends to 1650 m. in the White Mts. Also in northern Europe and Asia. 

 Summer. 



5. Agropyron Gmelini Scribn. & Sm. GMELIN'S WHEAT-GRASS. (I. F. f. 528a.) 

 Culms 4.5-12 dm. tall, tufted; leaves erect, 1-2.5 dm. l n g> 2 ~6 mm. wide, acumi- 

 nate, smooth beneath, scabrous on the margins and sometimes also sparsely so 

 above; spike slender, long-exserted, 5-20 cm. long; spikelets 6-20, somewhat 

 crowded, appressed to the rachis, more or less compressed, 5-9-flowered ; empty 

 scales 1-1.4 cm - l or >g> shorter than the spikelet, acuminate into a shorter awn; 

 flowering scales 8-12 mm. long, acuminate, bearing at or just below the apex a 

 slender scabrous awn 1.4-3 cm - lon g- Bottom lands, Wash, to western Neb. 



6. Agropyron tetrastachys Scribn. & Sm. COAST WHEAT-GRASS. (I. F. f. 

 524C.) Glaucous. Culms rigid, 4.5-9 dm. tall, from a running rootstock; leaves 

 erect, acuminate, 1.25-20 cm. long, 4 mm. or less wide, smooth beneath, glaucous 

 above, scabrous on the margins; spikes long-exserted, 7.5-12.5 cm. long, 4-sided; 

 spikelets crowded, 1.2-2 cm. long, 6-n-flowered, appressed to the 4-angled articu- 

 lated rachis, the angles hispidulous; empty scales lanceolate, I cm. long, 5-7- 

 nerved; flowering scales lanceolate, keeled, rough toward the apex, acute, awn- 

 pointed or short-awned. Sandy beaches, coast of Me. July- Aug. 



7. Agropyron spicatum (Pursh) Scribn. & Sm. WESTERN WHEAT-GRASS. 

 (I. F. f. 524b.) Pale green, glaucous. Culms 4.5-12 dm. tall, from a slender 

 creeping rootstock; leaves erect, 5-20 cm. long, 4-8 mm. wide, acuminate, very 

 scabrous above, smooth beneath, becoming involute when dry; spike strict, 1-2 

 dm. long; spikelets crowded, divergent from the rachis, compressed, lanceolate 

 when closed, 1.25-2.5 cm. long, 6-i2-flowered; empty scales acuminate, awn- 

 pointed, shorter than the spikelet, hispidulous on the keel; flowering scales 1-1.2 

 cm. long, acute or awn -pointed, glabrous or sparsely pubescent. Prairies and high 

 plains, Manitoba and Minn, to Ore., south to Mo. and Tex. 



8. Agropyron dasystachyum (Hook.) Vasey. NORTHERN WHEAT-GRASS. 

 (I. F. f. 525.) Glaucous. Culms 3-9 dm. tall, from long running rootstocks; leaves 

 522.5 cm. long, 26 mm. wide, flat, or becoming involute in drying, smooth be- 

 neath, rough above; spike 6.25-17.5 cm. in length; spikelets 4-8-flowered ; empty 

 scales 3-5 -nerved, lanceolate, acuminate or short-awned, 6-9 mm. long; flowering 

 scales broadly lanceolate, 5 -nerved, 9-12 mm. long, acute, or short-awned, densely 

 villous. Sand-hills and dunes, Hudson Bay to the N. W. Terr, and Wyo., and on 

 the shores of Lakes Huron and Superior. Summer. 



9. Agropyron pseudorepens Scribn. & Sm. FALSE COUCH-GRASS. (I. F. f. 

 524a.) Light green. Culms 39 dm. tall, from a running rootstock; leaves erect, 

 prominently nerved, rough on both surfaces, acuminate, the culm leaves 7.5-20 

 cm. long, 4-6 mm. wide, the basal leaves about one-half as long as the culms; 

 spikes 7.5-20 cm. long, strict; spikelets 1-1.6 cm. long, 3~7-flowered, a little com- 

 pressed, appressed to the rachis; empty scales lanceolate, equalling or somewhat 

 shorter than the spikelet, acuminate and often awn-pointed, 5-7-nerved, the nerves 

 hispidulous; flowering scales 5-nerved, roughish toward the apex, usually awn- 

 pointed. Rich river-bottoms, Mont, to Br. Col., south to Neb., Ariz, and Tex. 

 July-Aug. 



10. Agropyron repens (L.) Beauv. COUCH-GRASS. QUITCH-GRASS. (I. F. f. 

 524.) Culms 3-12 dm. tall, from a long- jointed running rootstock. Leaves 7.5- 

 30 cm. long, 2-10 mm. wide, smooth beneath, hirsute above; spike 5-20 cm. in 

 length, strict; spikelets 3-7-flowered; empty scales strongly 5-7-nerved, usually 

 acute or awn-pointed, sometimes obtuse; flowering scales smooth and glabrous, 

 acute or short-awned at the apex. In fields and waste places, almost throughout 

 N. Am. except the extreme north. Naturalized from Europe, and often a trouble- 

 some weed. Very variable. Native also of Asia. July-Sept. 



99. HORDEUM L. 



Annual or perennial grasses, with flat leaves and terminal cylindric spikes. 

 Spiklets I -flowered, usually in 3's at each joint of the rachis, the lateral generally 

 short-stalked and imperfect; rachilla produced beyond the flower, the lower empty 

 scales often reduced to awns and forming an apparent involucre around the spike- 



