Plants cespitose, not rhizomatous. Culms 15-35(55) cm, prostrate to strongly decumbent, at least at the base; nodes glabrous. Sheaths glabrous or shortly pilose; auricles usually present, 0.5-1 mm; ligules 0.2-0.4(0.7) mm, usually truncate, occasionally acute, entire to erose; blades 1.5-4 mm wide, usually involute, adaxial surfaces prominently ribbed. Spikes 3.5-10 cm long, 0.8-1.2 cm wide excluding the awns, 3-6 cm wide including the awns, usually with 1 spikelet per node, occasionally with 2 spikelets at the lower nodes; internodes 2.5-5(7) mm long, 0.5-1 mm wide, glabrous, mostly smooth, edges scabrous. Spikelets 9-15 mm long, 6-12 mm wide, appressed to ascending, with 3-6 florets; rachilla internodes 0.8-1.3 mm, scabridulous; disarticulation initially at the rachis nodes, subsequently beneath each floret. Glumes 4-9 mm long, 0.5-1 mm wide, mostly glabrous, midveins scabrous, 3-5-veined, entire, tapering into a divergent, 12-30 mm awn; lemmas 7-10 mm, usually glabrous, occasionally scabridulous, awned, awns 15-30 mm, divergent, scabridulous; paleas usually longer than the lemmas, apices ciliate, truncate or the veins extending into teeth, teeth about 0.5 mm; anthers 1-1.6 mm. 2n = 28.
Elymus scribneri grows in rocky areas in open subalpine and alpine regions, at 2500-3200 m, often in windswept locations, in southwestern Alberta and the western United States . It is often confused with E. elymoides , but differs from that species in having only one spikelet per node, wider glumes, and more tardily disarticulating rachises. It also resembles E. sierrae , from which it differs in its disarticulating rachises, denser spikes, and shorter anthers.
Several taxonomists have suggested that Elymus scribneri consists of fertile hybrids between E. violaceus -and E. elymoides . This suggestion is supported by the frequency with which the three taxa are sympatric, the morphological variation exhibited by E. scribneri, and cytogenetic data (Dewey 1967).
