Scientific Name
Danthonia californica Bol. (Synonyms: Danthonia americana)
Common Name(s)
California oatgrass, California danthonia, California wild oat-grass
Tribe / Family Name
Danthonieae
Flowering Period
June to August
Symbol
DACA3
Description
California oatgrass is a native cool-season perennial bunchgrass that spreads by seeds, tillers, and cleistogamous spikelets. Culms usually range from 30–80 cm in height. Its inflorescence is usually a raceme 2–7 cm long and bearing (2)3 to 6(10) spikelets with pedicels or lower branches that are divergent and spreading. Spikelets are broad, usually deep purple, 5- to 8-flowered, and awned (awns usually 8–12 mm long, twisted and flattened, geniculate, and attached below the lobes of the lemmas). Ligules are a fringe of hairs up to 0.5 mm long.
General Info
California oatgrass can be found in meadows, woodlands, sagebrush hills, grasslands, coastal prairies, and along mountain ridges, and prefers drier conditions.
Similar Species
California oatgrass can be confused with other oatgrasses, such as timber oatgrass (Danthonia intermedia) and onespike danthonia (Danthonia unispicata). To differentiate these plants from each other, look at the number of spikelets on the different types of inflorescences. California oatgrass has an open panicle or raceme with 3–5 spikelets, timber oatgrass has a narrow panicle or raceme with 5–10 spikelets, and onespike danthonia has a reduced single spikelet, but can sometimes have two or three. Another difference between California oatgrass and onespike danthonia are the stems. California oatgrass has glabrous stems, and onespike danthonia has uniquely hairy stems.
Picture of growth habit.
Inflorescence usually a raceme with (sometimes 2) 3-to 6 (sometimes 10) spikelets.
Close-up picture of spikelet.
Close-up picture of hairy ligule.
Illustration of California oatgrass. USDA-NRCS PLANTS Database / Hitchcock, A.S. (rev. A. Chase). 1950. <i>Manual of the grasses of the United States.</i> USDA Miscellaneous Publication No. 200. Washington, DC.
Distribution map of California oatgrass. USDA PLANTS database, 2022.