Mary E. Barkworth, Julian J.N. Campbell and Bjorn Salomon

Plants cespitose, not rhizomatous, sometimes glaucous, especially in the spikes. Culms 30–130 cm, erect to slightly decumbent; nodes 4–9, concealed or exposed, usually glabrous, rarely pubescent. Leaves evenly distributed; sheaths usually glabrous, rarely hirsute, occasionally reddish or purplish; auriclesabsent or to 1.8 mm, pale brown; ligules shorter than 1 mm; blades 2–14(18) mm wide, usually spreading or lax, sometimes becoming involute, basal blades similar to the upper blades, adaxial surfaces usually smooth , sometimes scabridulous, usually glabrous, occasionally pubescent. Spikes (3)4–16(22) cm long, 1–2.2(2.5) cm wide, erect, the bases often sheathed, with 2 spikelets per node, rarely with 3 at some nodes; internodes 3–5 mm long, 0.25–0.5 thick at the thinnest sections, smooth and glabrous, or scabrous, or with hairs beneath the spikelets. Spikelets 10–15 mm, appressed to slightly divergent, with (2)3–4(6) florets, lowest florets functional; disarticulation below the glumes and each floret, or the lowest floret often falling with the glumes. Glumes subequal or equal, the basal 1–4 mm terete, indurate, without evident venation, bowed out, yellowish, glume bodies 7–15 mm long, (0.5)0.7–2.3 mm wide, linear-lanceolate, widening above the base, 3–5(8)-veined, usually smooth or scabridulous, margins firm, awns 3–10(15) mm, straight; lemmas6–10 mm, scabridulous, glabrous or villous-hirsute, awns (5)8–20(25) mm, straight; paleas 5–9 mm, obtuse; anthers 2–3.5(4) mm. Anthesis usually mid-June to late July (mid-August). 2n = 28.

Elymus virginicus is widespread in temperate North America, growing as far west as British Columbia and Arizona. It is infrequent to rare in the Rocky Mountains, western Great Plains, and southeastern coastal plain. It is a complex species, divided here into four intergrading varieties.