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



Figure 545. — Distribution of 

 Sphenophoiis intermedia. 



size and in denseness of panicle. Sometimes annual or flowering the 

 first season. Specimens with less dense and lobed panicles may be 

 distinguished from denser panicled specimens of S. intermedia by the 

 broader, firmer, subcucullate second glume and more approximate 

 florets. 



2. Sphenophoiis intermedia (Rydb.) Rydb. Slender wedge- 

 grass. (Fig. 544, B.) Culms erect in small tufts, 30 to 120 cm tall; 



sheaths glabrous or pubsecent; blades flat, 

 often elongate, lax, mostly 2 to 6 mm wide, 

 sometimes wider, mostly scaberulous, occa- 

 sionally sparsely pilose; panicle nodding, from 

 rather dense to open, mostly 10 to 20 cm long, 

 the branches spikelet-bearing from base ; spike- 

 lets 3 to 4 mm long; second glume relatively 

 thin, acute or subacute, about 2.5 mm long; 

 lemmas subacute, rarely mucronate, smooth or 



rarely very minutely roughened, mostly 2.5 to 3 mm long. % — 



Damp or rocky woods, slopes, and moist places, Newfoundland to 



British Columbia, south to Florida and Arizona; Tanana Hot Springs, 



Alaska. (Fig. 545.) Delicate 



plants with small panicles resem- 

 bling S. nitida may be distinguished 



by the very narrow first glume, the 



acute to subacute second glume and 



lemmas, and usually by the glabrous 



foliage. Plants with rather dense 



panicles resembling S. obtusata may 



be distinguished by the thinner, less 



rounded, more compressed second 



glume. This is the species called 



Sphenophoiis pollens (Spreng.) 



Scribn. in recent manuals. Spreng- 



el's description of Aira pollens shows 



that Scribner misapplied the name 



(see no. 6). 



3. Sphenophoiis longiflora (Vasey) 

 Beal. (Fig. 546.) Culms relatively 

 stout, erect from a decumbent base, 

 40 to 70 cm tall ; lower sheaths pu- 

 berulent, the others glabrous ; blades 

 thin, flat, scaberulous, 5 to 18 cm 

 long, 3 to 8 mm wide; panicle many-flowered, rather loose, slightly 

 nodding, 10 to 18 cm long; spikelets mostly 2-flowered, the rachilla 

 hispidulous; glumes very scabrous on the green part, the second thin, 

 acute, about 3.5 mm long; lemmas smooth, scaberulous toward the 

 tip, the first about 4 mm long. % —Known only from Houston, 

 Tex. Differing from S. intermedia in the larger spikelets and broader 

 blades, and in the more tapering lemmas. 



4. Sphenophoiis nitida (Spreng.) Scribn. (Fig. 547.) Culms 

 tufted, leafy at base, slender, shining, 30 to 70 cm tall; sheaths and 

 blades mostly softly pubescent, occasionally glabrous, the blades 2 to 

 5 mm wide, 3 to 10 cm long, the basal sometimes longer; panicle 

 rather few-flowered, mostly 8 to 12 cm long, the filiform branches 



Figure 546.— Sphenophoiis longiflora. Panicle, 

 X 1; glumes and floret, X 10. (Nealley, Tex.) 



