438 MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



tufted, erect, slender, 30 to 70 cm* 

 tall; ligule about 1 mm. long; blades 

 scabrous, flat or involute, 0.5 to 2 

 mm. wide; panicle open, 10 to 15 

 cm. long, the branches distant, single 

 or in pairs, spreading or finally re- 

 flexed, 2 to 5 cm. long, with short- 

 pediceled appressed spikelets toward 

 the ends; glumes thin, acuminate, 

 3 to 4 mm. long; lemma elliptic, gla- 

 brous, or rarely appressed-pilose, 2 

 to 2.5 mm. long, yellow or brown, 

 the straight awn 5 to 10 mm. long. 

 % — Open dry woods and rocky 

 slopes, medium altitudes, Saskatche- 

 wan to North Dakota and Montana, 

 south to Nevada, New Mexico, Ari- 

 zona, and California (Mohave Des- 

 ert). The form with pilose lemmas is 

 found from Colorado to Arizona. 



3. Oryzopsis hendersoni Vasev. 

 (Fig. 627.) Culms densely tufted, 

 scabrous, 10 to 40 cm. tall; leaves 

 mostly basal, the sheaths broad, 

 papen^, glabrescent ; ligule very short ; 

 blades subfiliform, involute, scabrous, 

 firm, mostly less than 10 cm. . long, 

 the one or two culm blades 4 to 5 

 cm. long; panicle few-flowered, 5 to 12 

 cm. long, the few scabrous branches 

 appressed or ascending, spikelet-bear- 

 ing toward the ends, the lower as 

 much as 8 cm. long; spikelets short- 

 pediceled; glumes abruptly acute, 5 

 to 6 mm. long; lemma nearly as long 

 as the glumes, glabrous, dark brown 

 at maturity, the awn early deciduous, 

 nearly straight, 6 to 10 mm. long. 

 % — Diy or gravelly soil. Known 

 only from Mount Clements, Wash., 

 and from the Ochoco National Forest, 

 Oreg. 



4. Oryzopsis exigua Thurb. Little 

 ricegrass. (Fig. 628.) Culms densely 

 tufted, stiffly erect, scabrous, 15 to 

 30 cm. tall; sheaths smooth or some- 

 what scabrous; ligule 2 to 3 mm. 

 long; blades involute-filiform, stiffly 

 erect, scabrous, 5 to 10 cm. long, the 

 culm blades about 2, shorter; pan- 

 icle narrow, 3 to 6 cm. long, the 

 branches appressed, the lower 1 to 

 2 cm. long; spikelets short-pediceled, 



ilGURE 626. — Oryzopsis micrantha. Panicle, XI; 1 1 j_i l a i 



floret, x 5. (Hitchcock 22993, n. Mex.) glumes abruptly acute, 4 mm. long; 



Figure 625. — Oryzopsis miliacea, X 5. (Kralik, 

 Europe.) 



ma smooth, 2 mm. long, the straight 

 awn about 4 mm. long. % — 

 Introduced in California; ballast, 

 Camden, N. J., and Philadelphia, 

 Pa.; Mediterranean region. 



2. Oryzopsis micrantha (Trin. and 

 Pupr.) Thurb. Littleseed rice- 

 grass. (Fig. 626.) Culms densely 



