Polypogon viridis

Flora of Oregon

Plants perennial, often flowering the first year, 10–90 cm tall.

Leaves sheaths glabrous, smooth; ligules to 5 mm; blades 2–13 cm × 1–6 mm.

Inflorescences ovoid-oblong to pyramidal, interrupted, 2–10 cm; pedicels not developed; stipes 0.1–0.6 mm.

Glumes 1.5–2 mm, scabrous on the back and keel; tips obtuse to truncate, awnless.

Lemmas approximately 1 mm; tips erose, awnless.

Anthers 0.3–0.5 mm.

2n=28.

Mesic stream banks, rivers, ditches. 0–100m. Col, WV. CA, NV, WA; north to British Columbia, southeast to TX; Eurasia. Exotic.

This small grass resembles an Agrostis with unusually scabrous glumes, but its spikelets disarticulate below the glumes. Unlike other Polypogon species, it lacks glume awns. It has been collected from two sites along the Columbia River.

Herbarium specimens

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