OregonFlora: Polypogon viridis

	Polypogon viridis
	water beardgrass
Habit	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.

	Polypogon viridis
Distribution	[WildflowerSearch map] [BONAP county map]
Discussion	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.
Source	Flora of Oregon, volume 1, page 470 Barbara Wilson, Richard Brainerd, Nick Otting
Sibling taxa	P. australis, P. fugax, P. interruptus, P. maritimus, P. monspeliensis
Synonyms	Agrostis semiverticillata, Agrostis verticillata
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Polypogon viridis

water beardgrass

Habit

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.

=28.

Polypogon viridis

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

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.

Source

Flora of Oregon, volume 1, page 470
Barbara Wilson, Richard Brainerd, Nick Otting

Sibling taxa

P. australis, P. fugax, P. interruptus, P. maritimus, P. monspeliensis

Synonyms

Agrostis semiverticillata, Agrostis verticillata

Web links