Publication: Great Basin Naturalist 43(4): 570. 1983.
selected vouchers: WTU
Notes: "These have been shown to be sterile hybrids of sporadic occurrence, in this case mostly of Agropyron trachycaulum (A. caninum) and Hordeum jubatum parentage" [H&C].
FNA24: "xElyhordeum macounii consists of hybrids between Elymus trachycaulus and Hordeum jubatum. It is quite common in western and central North America. Backcrosses to E. trachycaulus may have non-disarticulating rachises; they are likely to be identified as E. trachycaulus, falling between subsp. trachycaulus and subsp. subsecundus. Artificial, partially fertile octoploids were distributed to natural and experimental areas in several western states prior to 1960 (Bowden 1960); it is not known whether they have persisted."