Western Wheatgrass

Pascopyrum smithii (Rydb.) A. Love
Western wheatgrass is a native cool-season perennial grass that grows from conspicuous white rhizomes, and is strongly rhizomatous. Western wheatgrass is a sub-dominant in plant communities with bluebunch wheatgrass and Idaho fescue, and is dominant on many sites on mixed-grass prairie east of the Rockies. On clay sites it is usually found with green needlegrass (Nassella viridula (Trin.) Barkworth - syn. Stipa viridula).
The shallow roots of western wheatgrass extend to 25 cm (10 in.) deep whereas feeder roots can be 150 cm deep (59 in.). The roots are known to creep aggressively in some conditions.
Smooth stems grow to 20 to 100 cm (8 to 39 in.) tall and are very erect. The leaves are rigid, flat, 6 mm wide, glaucous, blue, and grow at a 45 degree angle to the stem. The leaves are also ridged, rough, and veiny. The auricles are often purple, giving the plant its common name. Seed heads are 7 to 15 cm long (3 to 6 in.) dense spikes with single spikelets at each node. Each spikelet is 6 to 10 flowered glumes that are 10 to 12 mm long. They are rigid and almost flat sided in the middle not broadened.
Seeds are 10 to 12 mm long; the lemma sometimes having a short awn. Western wheatgrass is cross-pollinating often via wind, and is self-incompatible.