UW Burke Herbarium species comparison

Sheaths open, glabrous to hairy, usually with long hairs at the throat;

ligules a fringe of hairs 1-2 mm. long;

blades flat or slightly involute, glabrous or with soft hairs.

Sheaths open, usually glabrous, but with hairs 1-2 mm. long on the throat and collar;

ligule only 0.3-0.5 mm. long;

blades involute to flat, 1-3 mm. broad, somewhat curled.

Inflorescence a small, open panicle;

spikelets 2-5, several-flowered, at least 1 cm. long;

glumes 14-18 mm. long, the first 3-nerved, the second 5-nerved;

lemmas up to 14 mm. long, strongly bifid, the teeth awn-like, up to 4 mm. long, glabrous on the back, with marginal hairs, the callus short-bearded; awn attached just below the lobes of the lemma, flattened and twisted;

paleas broad, shorter than the lemmas.

Inflorescence a raceme-like panicle 3-6 cm. long, often one-sided, the short, erect branches usually bearing only one spikelet;

spikelets several-flowered;

glumes subequal, 13-17 mm. long;

lemmas 7-10 mm. long, glabrous on the back but hairy on the margins, bifid, the teeth acuminate, 1-2 mm. long; awn attached just below the lobes of the lemma, up to 10 mm. long;

callus strongly bearded;

paleas broad, shorter than the lemmas.

Utricle