Eriogonum umbellatum var. bahiiforme
Bay buckwheat, Bay Buckwheat
Photo: parent species Eriogonum umbellatum · Photo by Chez Brungraber
Family: Polygonaceae · Type: Subshrub · Native
Conservation status: CNPS 4.2
Eriogonum umbellatum var. bahiiforme (Bay buckwheat) is a native California subshrub in the Polygonaceae family, recognized by serpentine habitat preference helps narrow identification.
Bay buckwheat is a California native perennial ranked 4.2 by CNPS, found in northern coastal California and central western California regions in serpentine habitats at elevations of 700 to 2,000 meters. Flowering from July to September, this plant produces yellow flowers 5 to 8 millimeters long in compact umbel-like clusters. Growing as a dense mat 3 to 6 meters in diameter with stems 5 to 15 centimeters tall, it develops tomentose (woolly) stems and branches. Its leaves are small and densely woolly, with blades 5 to 15 millimeters long and 3 to 7 millimeters wide, creating a compact, low-growing form. The plant forms intricate involucre tubes 2 to 3 millimeters long with small teeth 2 to 3.5 millimeters in length.
Identification and appearance
Key characters: 45 sympatric species; serpentine habitat preference helps narrow identification
Habitat and range
Habitat: Serpentine
Elevation: 700-2000 m
California counties: San Bernardino, Mendocino, Glenn, Colusa, Contra Costa, Santa Clara, Los Angeles, San Benito, Lake, Calaveras, Monterey, Napa, Sonoma, Tehama, Trinity, Tulare, Siskiyou, Alameda, Kern, Santa Barbara, Ventura
Bloom period
Eriogonum umbellatum var. bahiiforme blooms Jul-Sep.
Conservation status
CNPS 4.2
How to tell it apart
vs Adenostoma: Eriogonum has flowers in cup-like involucres; Adenostoma has tiny white rose-family flowers in spikes.; vs Salvia: Eriogonum has six similar perianth parts; Salvia has two-lipped tubular flowers.; vs Fagopyrum: Eriogonum has flowers in involucred clusters; Fagopyrum has loose branching sprays without involucres.; vs Artemisia: Eriogonum has cup-surrounded flower clusters; Artemisia has tiny inconspicuous heads in drooping sprays.; vs Chorizanthe: Eriogonum has multiple flowers per involucre; Chorizanthe has one flower per involucre with spiny teeth.
Frequently asked questions
Is Eriogonum umbellatum var. bahiiforme native to California?
Yes. Eriogonum umbellatum var. bahiiforme is native to California (recorded as native).
When does Eriogonum umbellatum var. bahiiforme bloom?
Eriogonum umbellatum var. bahiiforme blooms Jul-Sep.
Where in California does Eriogonum umbellatum var. bahiiforme grow?
Eriogonum umbellatum var. bahiiforme occurs in San Bernardino, Mendocino, Glenn, Colusa, Contra Costa, Santa Clara, Los Angeles, San Benito and other counties, at elevations of 700-2000 m.
What plant family does Eriogonum umbellatum var. bahiiforme belong to?
Eriogonum umbellatum var. bahiiforme is in the Polygonaceae family, genus Eriogonum.
Is Eriogonum umbellatum var. bahiiforme rare or endangered?
Eriogonum umbellatum var. bahiiforme carries California Rare Plant Rank 4.2, state rank S3.
Related species
Other California species in the same genus, family, or bioregion.
- Eriogonum umbellatum var. canifolium — Sherman pass sulphur flower
- Eriogonum umbellatum var. chlorothamnus — Sherwin grade sulphur flower
- Eriogonum umbellatum var. covillei — Coville's sulphur flower
- Eriogonum umbellatum var. dichrocephalum — Bicolor sulphur flower
- Eriogonum umbellatum var. dumosum — American valley sulphur flower
- Eriogonum umbellatum var. furcosum — Sierra nevada sulphur flower
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
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.