2. Hordeum pusillum Nutt. (little barley)

Pl. 187 e, f; Map 759

H. riehlii Steud.

Plants annual. Flowering stems 10–50 cm long, the nodes dark brownish black. Leaf sheaths glabrous or with spreading hairs. Leaf blades 1–12 cm long, 2.0–4.5 mm wide, glabrous or hairy, without auricles at the base. Inflorescences 2–8 cm long (excluding the awns), erect, disarticulating at the nodes of the axis, the joints shed as a unit with the attached spikelets. Spikelet clusters with the central spikelet fertile and the 2 lateral spikelets sterile and with reduced florets. Glumes 7–15 mm long (including the awns), those of the central spikelet and sometimes of the lateral spikelets flattened and slightly broadened at the base, relatively stout, straight, erect or ascending. Lemma of the fertile florets with the body 5–7 mm long, narrowly elliptic, tapered to an awn 4–8 mm long, the awns relatively stout, straight, erect or ascending. Anthers 0.5–0.8 mm long. Fruits 2.7–3.2 mm long. 2n=14. April–June.

Scattered to common, mostly north of the Missouri River (southern U.S. and adjacent Mexico north to Delaware, Illinois, and Washington; South America; apparently introduced farther north in the U.S. and Canada). Disturbed areas of mesic upland forest, banks of streams and rivers, and margins of lakes and ponds; more commonly pastures, crop fields, fallow fields, roadsides, railroads, and open, disturbed areas.