Alopecurus geniculatus
Water foxtail, Water Foxtail
(c) Вячеслав Юсупов, some rights reserved (CC BY) · licence
Family: Poaceae · Type: Grass · Native
Alopecurus geniculatus (Water foxtail) is a native California grass in the Poaceae family, recognized by large anthers and aquatic habitat preference.
Water foxtail is a California native perennial found in northwestern, high Cascade Range, Sierra Nevada, central Coast, southern Coast, and Great Basin regions in open, wet meadows, pools, shores, and streambanks at elevations below 3,200 meters. Flowering from May to June, this plant produces pale green to whitish flowers in dense, cylindrical spikes 1.5 to 6 centimeters long. Growing with slender, bent or geniculate stems 14 to 55 centimeters tall, it forms loose tufts in moist environments. Its leaf blades are narrow, measuring 2 to 8 centimeters long and 1 to 4 millimeters wide, with a distinctive ligule 2.5 to 5 millimeters long. The flower's lemma features a bent awn that extends 2 to 3.5 millimeters beyond the lemma body, giving the plant a delicate, feathery appearance.
Identification and appearance
Key characters: 6 sympatric species; distinguished by large anthers and aquatic habitat preference
Habitat and range
Habitat: Open, wet meadows, pools, shores, streambanks
Elevation: < 3200 m
California counties: Alpine, Humboldt, Lassen, Los Angeles, Modoc, Plumas, Marin, Mono, Tulare, Lake, San Bernardino, Sonoma, Shasta, Mendocino, Fresno, Del Norte, Tehama, Butte, Sierra, San Mateo, Tuolumne
Outside California: to British Columbia, eastern North America, Eurasia
Bloom period
Alopecurus geniculatus blooms May-Jun.
How to tell it apart
vs Hordeum: Alopecurus has soft, single bristles; Hordeum has stiff, spreading bristles in groups of three.; vs Phalaris: Alopecurus has bristles from each flower; Phalaris has awnless, egg-shaped spikes.; vs Phleum: Alopecurus has a bristle from each flower; Phleum is awnless with a smoother cylinder.; vs Plantago: Alopecurus is a grass; Plantago has broad, basal leaves and is not a grass.; vs Cenchrus: Alopecurus has a fuzzy cylinder; Cenchrus has spiny burs enclosing seeds.
Frequently asked questions
Is Alopecurus geniculatus native to California?
Yes. Alopecurus geniculatus is native to California (recorded as native).
When does Alopecurus geniculatus bloom?
Alopecurus geniculatus blooms May-Jun.
Where in California does Alopecurus geniculatus grow?
Alopecurus geniculatus occurs in Alpine, Humboldt, Lassen, Los Angeles, Modoc, Plumas, Marin, Mono and other counties, at elevations of < 3200 m.
What plant family does Alopecurus geniculatus belong to?
Alopecurus geniculatus is in the Poaceae family, genus Alopecurus.
What habitat does Alopecurus geniculatus grow in?
Alopecurus geniculatus grows in Open, wet meadows, pools, shores, streambanks.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.