MANUAL OF THE GRASSES OF THE UNITED STATES 

 56. SPHENOPHOLIS Scribn. Wedgegrass 



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Spikelets 2- or 3-flowered, the pedicel disarticulating below the glumes, the 

 rachilla produced beyond the upper floret as a slender bristle; glumes unlike in 

 shape, the first narrow, usually acute, 1-nerved, the second broadly obovate, 

 3- to 5-nerved, the nerves sometimes obscure, mostly somewhat coriaceous, 

 the margin scarious; lemmas firm, scarcely nerved, awnless or rarely with 

 an awn from just below the apex, the first a little shorter or a little longer 

 than the second glume; palea hyaline, exposed. Slender perennials (rarely 

 annual) with usually flat blades and narrow shining panicles. Type species, 

 Sphenopholis obtusata. Name from Greek sphen, wedge, and pholis, horny 

 scale, alluding to the hard obovate second glume. 



All the species are forage grasses but are usually not abundant. The most 

 important are S. intermedia and S. obtusata. 



Panicle dense, usually spikelike, erect or nearly so; second glume subcucullate. 



1. S. OBTUSATA. 

 Panicle not dense, lax, nodding, from very slender to many-flowered, but not spikelike. 



Spikelets awned 6. S. pallens. 



Spikelets awnless (rarely awned in S . filiformis) . 



Lemmas glabrous; second glume acute or subacute; panicle many-flowered. 



Second glume about 2.5 mm. long 2. S. intermedia. 



Second glume about 3.5 mm. long 3. S. longiflora. 



Lemmas scabrous; second glume broadly rounded at the summit; panicle relatively 

 few-flowered. 



Blades rarely more than 10 cm. long, flat, 2 to 5 mm. wide 4. S. nitida. 



Blades elongate, flat to subinvolute, mostly less than 2 mm. wide.... 5. S. filiformis. 



1. Sphenopholis obtusata (Michx.) 

 Scribn. Prairie wedgegrass. (Fig. 

 380.) Culms erect, tufted, 30 to 100 

 cm. tall ; sheaths glabrous to finely re- 

 trorsely pubescent; blades flat, gla- 

 brous, scabrous, or pubescent, mostly 

 2 to 5 mm. wide; panicle erect or 

 nearly so, dense, spikelike to inter- 

 rupted or lobed, rarely slightly looser, 

 5 to 20 cm. long; spikelets 2.5 to 3.5 

 mm. long, the two florets closer to- 

 gether than in the other species; sec- 

 ond glume very broad, subcucullate, 

 somewhat inflated at maturity, 5- 

 nerved, scabrous; lemmas minutely 

 papillose, rarely mucronate or with a 

 short straight awn, the first about 2.5 

 mm. long. 91 — Open woods, old 

 fields, moist ground, and prairies, 

 Maine to British Columbia, south to 

 Florida, Arizona, and California; 

 Mexico; Dominican Republic. Vari- 

 able in size and in denseness of pan- 

 icle. Sometimes annual or flowering 

 the first season. Specimens with less 

 dense and lobed panicles may be dis- 

 tinguished from denser panicled speci- 

 mens of S. intermedia by the broader, 

 firmer, subcucullate second glume and 

 more approximate florets. 



Figure 379. — Koeleria phleoides. Panicle. X 1 ; glumes 

 and floret, X 10. (Heller 11417, Calif.) 



2. Sphenopholis intermedia 



(Rydb.) Rydb. Slender wedge- 

 grass. (Fig. 381.) Culms erect in 

 small tufts, 30 to 120 cm. tall; sheaths 

 glabrous or pubescent; blades flat, 

 often elongate, lax, mostly 2 to 6 mm. 

 wide, sometimes wider, mostly sea- 



