Avena sativa is an annual C3 grass (Pascal-Antoine 2008) to 1 m tall.
Leaves alternate, ligules 0.2-0.6 cm membranous, blade rough, to slightly hairy, 0.3-1 cm wide.
Flowers: Spiklets 2 flowered, nodding, axis smooth, glumes 2- 2.5 cm long, with 9-11 veins; lemma 1.5-2 cm, hard, sometimes awned, 2.5-3.5 cm long; inflorescence 10-25 cm or more, open, branches horizontal; blooming and fruiting July-Oct.
Wetland status: UPL.
Frequency in NYC: Very infrequent.
Habitat: Disturbed sites. Sometimes introduced from hay bales at construction sites. Generally not persistent (Gargiullo personal observation).