GPwAMlNEAE (GRASS FAMILY) 



123 



* * Spikelets^ excluding aimi, 6-9 mm. long. 



• 



2. 0. asperif51ia Miclix. Culms tufted, 2-7 dm. bigh, erect or geniculate at 

 the lowest node; sheaths usually crov:ded at the base; blades erect, scabrous 

 especially on the glaucous lower surface, those of the base 

 often exceeding the culm, 5-8 mm. wide, flat or involute on 

 the margins, attenuate; culm-leaves usually less than 1 cm. 

 long ; panicle contracted. 5-12 cm. long., the branches simple, 

 erect ; spiJcelets, excluding awn, 6-8 mm. long ; glumes subequal, 

 shoit-ciliate at the apiculate summit ; lemma nearly or quite as 

 long as the second glume, sparingly pubescent ; avm 5-10 mm. 

 long; lodicules | the length of the pale a. — 

 Wooded hillsides, along waterways, etc., Nfd. 

 to B. C, s. to Pa., Minn., and N. Mex. June. 

 Fig. 80. 



3. 0. racembsa (Sm.) Kicker. Culms tufted, 

 erect, ^3-12 dm. high, leafy to the summit ; leaves 

 1-3.5 dm. long. 4-15 mm. wide, flat, narrowed 

 toward the base, taper-pointed, scabrous below., 

 pubescent above ; panicle 7-25 cm. long, branches 

 nearly simple, usually ascending ; -sp^Xv/ei. excluding awn, 1-9 mm. 

 long ; glumes equal, acute ; lemma somewhat shorter, pubescent, 

 becoming black in fruit; awn 1.5-2.5 cm. long; lodicules minute. 

 (?Iilium Sm. ; 0. melanocarpa Muhl.) — Rocky woods, Me. to 

 Ont., southw. to Del. and la. June-Oct. Fig. 81. 



80. O. a^jierilblia 



Spikelet (below). 

 Floret (above). 



81. O. racemosa. 

 Spikelet x 1. 



24. STIPA L. Feather Grass 



Spikelets 1-flowered, in terminal panicles ; glumes narrow, acute or bristle- 

 tipped ; floret with a bearded usually sharp-pointed callus ; lemma convolute, 

 indurated, including the small palea and perfect flower, terminating in a simple 

 strong persistent geniculate twisted awn ; grain cylindrical, tightly included 

 in the indurated fruiting lemma. — Rather large tufted perennials with involute 

 leaves. (Name from o-ti^tt??, tow, in allusion to the flaxen appearance of the 

 feathery awns of the original species.) 



* Glumes 4:-l2 mm. long. 

 •*- Callus blunt; awn 1 cm. or less long. 



1. S. canadensis Poir. Culms tufted, 3-6 dm. high ; leaves 4-12 cm. long, 

 narrow, involute, scabrous ; panicle loose, 5-12 cm. long, the opposite few- 

 flowered branches ascending ; glumes subequal, oblong, subacute, 4 mm. long, 

 slightly exceeding the pubescent oblong lemma ; awn 6-10 mm. long. {S. 

 Richardsoni Man. ed. 6, not Link ; S. Macounii Scribn.) — Woods and thickets, 

 N. B., Me., N. H., N. Y., n. shore of L. Superior, Sask., and north w. 



•*- +- Callus acute; awn more than 1.5 cm long. 



2. S. viridula Trin. XI!ulms clustered, 5-10 dm. bigh, 

 sparingly branched ; basal sheaths overlapping, the long 

 usually scabrous involute or sub-involute blades elongated, 

 upper blades shorter, mostly setaceous ; panicle narrow, 

 erect, 1-2 dm. long, the branches mostly in pairs, erect, 

 rather densely flowered from near the base ; glumes 7-9 mm. 

 long, acuminate-setaceous, exceeding the pale appressed- 

 pubcscent I einma ; R\\n 2-4: cm. long; callus usually rather 

 sJwrt. — Prairies and meadows, w. Minn., the Dakotas, and 

 soutbwestw. July, Aug. — Variable. 



3. S. avenacea L. (Black Oat Grass.) Culms tufted, 

 slender, erect or ascending, 3-10 dm. high, leafy at the base ; 

 sheaths shorter than the internodes ; blades 1-1.5 mm. wide, 

 usually involute, the basal ones i-^ the length of the culms, 



82. S. avenacea x 1% 

 Flower and glumes. 



