142 



GRAMINEAE (^GRASS FAMILY) 



Teeth of the lemma trianorular, not aristate 1. D. spicata. 



Teeth of the lemma aristate. 



Florets not over 5 mm. long 2. 2). compressa. 



Florets 7-8 mm. long. 

 Spikelets nearly sessile, in small crowded panicle, purple , , . . 8. 2). intermedicu 

 Spikelets in loose panicle, pale green. 



Sheaths and blades villous ; lemma silky-hairy 4. Z>. sericea. 



Sheaths and blades glabrous ; lemma pubescent on margins and base 



only 5, B. epilis, 



1. D. spicata (L.) Beaiiv. Culms 2-7 dm. high terete ; sheaths and involute 

 blades glabrous or sparsely pilose, the numerous basal leaves often curled, those 

 of the culm erect ; panicle fevsr-flowered, the few short branches 

 erect or ascending, often reduced to a raceme ; spikelets 

 10-12 mm. long, on short stiff pedicels ; glumes acuminate : 

 lemmas 4-5 mm. long, sparsely clothed with stiff hairs, teeth 

 ' triangular^ the awn longer than the lemma. — Dry and sterile 



or rocky soil. June-Aug. Fig. 126. 



2. D. compressa Aust. Usually taller than the preceding ; 

 culms flattened, often decumbent at base ; leaves elongated, 

 2-3 mm. loide, flat or involute on the margins only; panicle 

 more open ; teeth of the lemma aristate, at least 

 2 mm. long. — Dry woods, Me. to N. Y., and 

 south w. 



3. D. intermedia Vasey. Culms 1-4 dm. high, 

 with numerous mostly involute basal leaves ; 

 culm-leaves 5-15 cm, long, involute ; spikelets 



W^WM' 15 mm. long, rather crowded in a raceme or 



simple few-flowered panicle ; glumes hroad, acu- 



minate, purplish, with pale scarious margins; 



. . spica . if^Yii^yid 7_8 mm. long, glabrous except at the base 



B -T 1 f^ 1 fl ^^^^ margins below the middle, the teeth aristate ; 



Bpikeiet and floret ^^^^^ ._g ^^^_ long. — Ut. Albert, Gaspd Co., 



Lemma X 2 Que.; n. Mich. (Farwell)^ and westw. July, 



Aug. 



4. D. sericea Nutt. Culms 5-9 dm. high ; sheaths and blades 

 villous, at least the lower ones ; basal blades elongated, mostly 

 involute, those of culms flat or involute ; panicle 6-10 cm. long, 

 rarely longer, rather loose, the branches ascending or spreading ; 

 spikelets about 1.5 mm. long; glumes narrow, acuminate, pale; 

 lemma densely clothed with long silky hairs, the aristate teeth more ^27 d sericea 

 than \ the entire length of the lemma, awn 12-15 mm. long. — Lemma x 4 

 Sandy soil, Mass. to Pa., and southw. Fig. 127. 



5. D. epilis Scribn. Very similar to the preceding, not so tall ; sheaths and 

 blades glabrous ; panicle smaller ; lemma glabrous, except at the base and on the 

 margins below the middle. (Z>. glabra Nash, not Philippi.) — Sandy soil, N. J., 

 and southw., rare. May. — Possibly only a variety of the preceding. 



48. SPARTINA Schreb. Cord or Marsh Grass 



Spikelets 1-flowered, flattened laterally, sessile and closelj imbricated in 2 

 rows along one side of a continuous rhachis, forming unilateral spikes which are 

 scattered along a common axis ; glumes unequal, keeled, acute or bristle- 

 pointed, the second usually exceeding the obtuse thinner 1-nerved lemma ; 

 palea equaling or exceeding the lemma. — Coarse perennials T^ith strong creeping 

 rootstocks, rigid simple culms, and long tough leaves. (WTience the name, from 

 (TirapTLVT], a cord, such as was made from the bark of the Spartium or broom.) 



* Culms stout, usually over 1 m. high; leaves 1 cm. or more wide, flat of 

 nearly so when fresh. 

 1. S- Michauxi^na Hitchc. (Slough Grass.) Culms 1-2 m. high; 

 leaves &-12 dm. long, 15 mm. wide or less, tapering to a very slender point, 



