Calamagrostis nutkaensis
Pacific reed grass
(c) Nicholas Wei, some rights reserved (CC BY-SA), uploaded by Nicholas Wei · licence
Family: Poaceae · Type: Grass · Native
Calamagrostis nutkaensis (Pacific reed grass) is a native California grass in the Poaceae family, recognized by exceptionally wide smooth leaves in coastal wet habitats.
Pacific reed grass is a California native perennial found in northern coastal, central coastal, and San Francisco Bay bioregions in wet areas, beaches, dunes, coastal woodland, and inland marshes at elevations below 1,070 meters. Flowering from May to August, this grass produces pale green to whitish flowers in narrow, open inflorescences 12 to 30 centimeters long. Growing in dense tufts with stout rhizomes, it develops robust stems 6 to 11 decimeters tall that are generally unbranched below. Its leaf blades are flat and 4 to 10 millimeters wide, with smooth upper surfaces and a distinctive truncate ligule mostly hidden by an expanded collar. The plant forms delicate, slightly twisted awns 1 to 3 millimeters long emerging from its lemmas, giving it a subtle, textured appearance in coastal and wetland environments.
Identification and appearance
Key characters: 7 sympatric species; key feature is exceptionally wide smooth leaves in coastal wet habitats
Habitat and range
Habitat: Wet areas, beaches, dunes, coastal woodland, inland marshes
Elevation: < 1070 m
California counties: Humboldt, Alameda, Del Norte, Marin, Mendocino, San Mateo, Sonoma, Monterey, San Francisco, San Luis Obispo, Santa Cruz, Siskiyou
Outside California: to Alaska
Bloom period
Calamagrostis nutkaensis blooms May-Aug.
How to tell it apart
vs Leymus: Leymus has spike-like inflorescences; Calamagrostis has open, branching panicles.; vs Koeleria: Koeleria has dense spike-like panicles; Calamagrostis panicles are loose and open.; vs Holcus: Holcus has velvety-hairy spikelets; Calamagrostis has silky basal hairs only.; vs Muhlenbergia: Calamagrostis spikelets are 2-4mm with awns; Muhlenbergia often larger without prominent awns.; vs Spinifex: Spinifex forms spiny seed heads on beaches; Calamagrostis has soft panicles in mountains.
Frequently asked questions
Is Calamagrostis nutkaensis native to California?
Yes. Calamagrostis nutkaensis is native to California (recorded as native).
When does Calamagrostis nutkaensis bloom?
Calamagrostis nutkaensis blooms May-Aug.
Where in California does Calamagrostis nutkaensis grow?
Calamagrostis nutkaensis occurs in Humboldt, Alameda, Del Norte, Marin, Mendocino, San Mateo, Sonoma, Monterey and other counties, at elevations of < 1070 m.
What plant family does Calamagrostis nutkaensis belong to?
Calamagrostis nutkaensis is in the Poaceae family, genus Calamagrostis.
What habitat does Calamagrostis nutkaensis grow in?
Calamagrostis nutkaensis grows in Wet areas, beaches, dunes, coastal woodland, inland marshes.
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.