Culms 40-80 cm, disarticulating at the nodes when mature.
Sheaths glabrous, rarely sparsely pilose, usually reddish above the nodes;
blades to 30 cm long, 2-4 mm wide, flexible but not curled at maturity,
glabrous, sometimes scabrous, uppermost cauline blades erect to ascending. Inflorescences
with (4)6-17 spikelets; branches usually flexible, usually divergent,
sometimes strongly so, after anthesis; lower branches with 2-3 spikelets;
pedicels on the lowest branch as long as or longer than the spikelets.
Spikelets (7)10-16 mm. Calluses of middle florets about as long
as wide, convex abaxially; lemma bodies 2.5-5 mm, pilose over the back,
sometimes sparsely so, margins pilose to beyond midlength, distal hairs 0.5-2
mm, apical teeth 2-4 mm, aristate, (1/2)2/3 or more as long as the lemma bodies;
awns 6-10 mm; anthers to 2.2 mm. Caryopses 1.7-2.6 mm long,
0.7-1.1 mm wide. 2n = 36.
Danthonia compressa grows in open and semi-shaded areas, including meadows,
open woods, and woodland openings. Although not a true pioneer species, it may
sometimes occur as a weed in perennial crops. It is restricted to eastern North
America.
Much like no. 2 [Danthonia spicata (L.) Roem. & Schult.] and perhaps not sharply distinct; stem very slender, flattened, 4-8 dm; sheaths glabrous; blades usually flat, often to 20 cm, 2-4 mm wide, scaberulous; infl lax, 5-10 cm, the filiform branches often reflexed at anthesis, at least the lower branches with 2 or 3 spikelets; glumes 9-13 mm; lemmas 4.5-8 mm, of which the teeth constitute half, sparsely pilose on the back; awn 5.5-8 mm; 2n=36. Dry woods; N.S. and Que. to O., N.C., and Tenn.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
