Mary E. Barkworth, Julian J.N. Campbell and Bjorn Salomon
Plants rhizomatous. Culms about 60 cm, erect. Leaves somewhat basally concentrated; blades 3.5–6 mm wide. Spikes 6–10 cm long, 0.7–1.7 cm wide, with 1 spikelet per node; internodes 6–11 mm. Glumes 4–5.5 mm, about 1/2 the length of the adjacent lemmas, lanceolate, flat, hairy, apices acute or awn-tipped, awns shorter than 1 mm; rachillas densely hairy; lemmas 6–9 mm, densely villous, unawned; anthers 3.3–3.6 mm.
The parents of E. ×yukonensis have not been identified. Morphological and geographic considerations suggest that they may be E. lanceolatus subsp. psammophilus and E. alaskanus.