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



14. Stipa lepida Hitchc. Foothill needlegrass. (Fig. 904.) 

 Culms slender, puberulent below the nodes, 60 to 100 cm tall; sheaths 

 smooth, rarely puberulent, sparingly villous at throat; ligule very 

 short; blades 10 to 30 cm long, flat, 2 to 4 mm wide, pubescent on 

 upper surface near base; panicle rather loose and open, usually 15 to 

 20 cm long, sometimes more than 30 cm long, 

 the branches distant, slender; glumes 3-nerved, 

 smooth, acuminate, the first 6 to 10 mm long, ^LMr 



the second about 2 mm shorter; lemma about 6 MW 



mm long, brown, sparingly villous, nearly gla- /$Wl? 



brous toward the hairy-tufted apex; awn in- 

 distinctly twice-geniculate, about 2.5 to 4 cm 



Figure 904— Stipa lepida. Floret, 

 X 1; lemma, X 5. (Chase 5609, 

 Calif.) 



Figure 905.— Stipa porteri. Floret, 

 X 1; lemma, X 5. (Wolf 1109. 

 Colo.) 



Figure 906.— Stipa thurberiana 

 Floret, X 1; lemma, X 5. 

 (Chase 4689, Idaho.) 



long, scabrous. Q[ — Dry hills, open woods, and rocky slopes, 

 central California to Baja California, in the Coast Range. Stipa 

 lepida var. andersoni (Vasey) Hitchc. Differing only in the more 

 slender culms, the slender involute blades, and in the narrow or 

 reduced panicle. — Same range as the species. 



15. Stipa porteri Rydb. (Fig. 905.) Culms 20 to 35 cm tall; 

 ligule 2 to 3 mm long; blades 2 to 12 cm long, involute, subfiliform, 

 sulcate, scaberulous; panicle mostly 5 to 10 cm long, open, the 

 branches distant, capillary, flexuous, few-flowered; glumes 5 to 6 

 mm long; lemma about 5 mm long, oblong-elliptic, softly pilose on 

 the lower half, scaberulous above, lobed at 

 summit; awn 12 to 15 mm long, plumose with 

 hairs 1 to 2 mm long, with a single bend one- 

 third from the base, the first segment weakly 

 twisted. % — High mountains of Colorado. 



16. Stipa thurberiana Piper. Thurber 

 needlegrass. (Fig. 906.) Culms mostly 30 

 to 60 cm tall; sheaths scaberulous or the upper 

 glabrous; ligule hyaline, 3 to 6 mm long; blades 



10 to 25 cm long, filiform, involute, scabrous, flexuous; panicle mostly 

 8 to 15 cm long, narrow, the ascending branches few flowered ; glumes 



1 1 to 13 mm long, the acuminate summit hyaline ; lemma 8 to 9 mm long, 

 appressed-pubescent, callus about 1 mm long; awn 4 to 5 cm long, 

 twice-geniculate, the first and second segments plumose with hairs 1 

 to 2 mm long. % — Mesas and rocky slopes. Idaho to Washing- 

 ton and central California (fig. 907). 



Figure 907.— Distribution of 

 Stipa thurberiana. 



