1. Aira caryophyllea L. (silver hairgrass)

Pl. 130 e, f; Map 529

Flowering stems 5–30 cm long. Inflorescences 2–10 cm long, broadly ovate in outline, the spikelet stalks 2–5 mm long, mostly 1–2 times as long as the spikelets. Glumes 2.2–3.0 mm long. Lemmas 1.8–2.3 mm long, both awned, the awns 2.4–3.3 mm long. 2n=14, 28. May–June.

Introduced, uncommon, mostly in the southern portion of the Ozark Division (native of Europe, Asia, Africa; introduced in the U.S. and adjacent Canada, South America, southern Africa, Australia, and New Zealand). Occasionally along margins of igneous glades; also lawns, pastures, old fields, paths, roadsides, and disturbed, open areas.

This species was first reported for Missouri independently by Castaner (1982) and Dunn (1982).