Damasonium californicum
California damsonium
(c) Marco Iboshi, some rights reserved (CC BY) · licence
Family: Alismataceae · Type: Herb · Native
Damasonium californicum (California damsonium) is a native California herb in the Alismataceae family, recognized by Western North American endemic genus, representing relict lineage in water-plantain family.
California damsonium is a California native perennial found in northern California Interior Coast Ranges, northern Sierra Nevada Foothills, Great Valley, northwestern San Francisco Bay Area, and northern North Coast Ranges in ponds, vernal pools, and streams at elevations below 1,700 meters. Flowering in late summer, this plant produces white flowers with yellow basal spots and red anthers. Growing with delicate stems reaching up to 35 centimeters tall, it emerges from wet seasonal habitats. Its leaves are linear to narrowly ovate, typically 3 to 9 centimeters long and 0.5 to 3 centimeters wide, often longer than their supporting stems. The fruit develops a distinctive body 3 to 5.5 millimeters long with a slender beak extending 3 to 6 millimeters.
Identification and appearance
Key characters: Western North American endemic genus, representing relict lineage in water-plantain family
Habitat and range
Habitat: Ponds, vernal pools, streams
Elevation: < 1700 m
California counties: Mendocino, Sacramento, Lassen, Placer, Butte, Plumas, Merced, Sutter, Yolo, Marin, Solano, Colusa, Modoc, San Joaquin, Glenn, Sonoma, Tehama, Sierra, Yuba, Kern, Mariposa, San Mateo, Siskiyou, Tuolumne, Lake, Shasta, Stanislaus, Napa, Amador, Calaveras
Outside California: to Oregon, Idaho, Nevada
Bloom period
Damasonium californicum blooms Late summer.
How to tell it apart
vs Echinodorus: Damasonium fruits form a flat star; burhead fruits form a domed spiky bur.; vs Sagittaria: Damasonium fruits fuse at base in a star; arrowhead fruits are separate and spiral on a dome.; vs Alisma: Damasonium fruits fuse at base forming a star; alisma fruits are separate in a flat ring.
Frequently asked questions
Is Damasonium californicum native to California?
Yes. Damasonium californicum is native to California (recorded as native).
When does Damasonium californicum bloom?
Damasonium californicum blooms Late summer.
Where in California does Damasonium californicum grow?
Damasonium californicum occurs in Mendocino, Sacramento, Lassen, Placer, Butte, Plumas, Merced, Sutter and other counties, at elevations of < 1700 m.
What plant family does Damasonium californicum belong to?
Damasonium californicum is in the Alismataceae family, genus Damasonium.
What habitat does Damasonium californicum grow in?
Damasonium californicum grows in Ponds, vernal pools, streams.
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.