Comprehensive DescriptionRead full entry
General: Squirreltail is a cool-season C-3 bunchgrass native to the western United States. Foliage can be glabrous but is more often white hairy throughout. Plants are short, 10 to 45 cm (4 to 25 inches) tall, with culms erect to spreading. Leaf blades are flat to involute, 1 to 6 mm (0.04 to 0.24 inches) wide. The inflorescence is a spike from 2 to 17 cm (0.8 to 6.7 inches) long, not counting the awns. Internodes of the inflorescence are from 2 to 10 mm (0.08 to 0.40 inches) long with the rachis disarticulating regularly. At maturity the spike can be over 12 cm (4.7 inches) wide due to the widely spreading awns. Awns are scabrous and may grow from 2 to as much as 10 cm (0.8 to 3.9 inches) long, these often becoming purple with maturity.
Squirreltail is a self-pollinating allotetraploid and is known to hybridize with other species of Elymus as well as with members of Hordeum (barley) and Pseudoroegneria (bluebunch wheatgrass). Plants flower from late May to August.
Distribution: Squirreltail (in the broad sense) can be found throughout western North America from Canada to Mexico. For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site.
Habitat: Bottlebrush and big squirreltail grow in a wide range of habitats, from shadscale communities to alpine tundra. Elymus elymoides ssp. elymoides is common at low to middle elevations in the western states. Subspecies californicus is native to mid-elevations up to alpine areas of Canada, California, Nevada and Utah. Subspecies brevifolius is found in a wide variety of habitats including desert and mountain plant communities, while subspecies hordeoides is restricted to the low lands of the Great Basin. Elymus multisetus occupies a similar range to ssp. elymoides, but is typically found in somewhat wetter, more mesic sites often in and near mountain foothills.