Eriogonum umbellatum var. argus
One-eyed sulphur flower, One-Eyed Sulphur Flower
Photo: parent species Eriogonum umbellatum · Photo by Chez Brungraber
Family: Polygonaceae · Type: Subshrub · Native
Eriogonum umbellatum var. argus (One-eyed sulphur flower) is a native California subshrub in the Polygonaceae family, recognized by serpentine habitat and wavy leaf margins distinctive.
One-eyed sulphur flower is a California native perennial found in the Klamath Ranges and north-central Coast Ranges in serpentine habitats at elevations of 1,500 to 2,200 meters. Flowering from June to September, this plant produces vibrant yellow flowers in delicate umbel-like clusters. Growing as a mat-forming plant up to 15 meters in diameter with stems 10 to 20 centimeters tall, it develops woolly or hairy stems often featuring a leaf-like bract near the middle. Its leaves are small, one to two centimeters long with wavy margins, tomentose on the undersides and varying from hairy to glabrous. The plant forms dense, low-growing mats characteristic of its serpentine habitat adaptation.
Identification and appearance
Key characters: 39 sympatric species; serpentine habitat and wavy leaf margins distinctive
Habitat and range
Habitat: Serpentine
Elevation: (900)1500-2200 m
California counties: Siskiyou, Trinity, Del Norte, Humboldt, Inyo, Tehama, Glenn, Shasta, El Dorado, Plumas
Outside California: southwestern Oregon
Bloom period
Eriogonum umbellatum var. argus blooms Jun-Sep.
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. argus native to California?
Yes. Eriogonum umbellatum var. argus is native to California (recorded as native).
When does Eriogonum umbellatum var. argus bloom?
Eriogonum umbellatum var. argus blooms Jun-Sep.
Where in California does Eriogonum umbellatum var. argus grow?
Eriogonum umbellatum var. argus occurs in Siskiyou, Trinity, Del Norte, Humboldt, Inyo, Tehama, Glenn, Shasta and other counties, at elevations of (900)1500-2200 m.
What plant family does Eriogonum umbellatum var. argus belong to?
Eriogonum umbellatum var. argus is in the Polygonaceae family, genus Eriogonum.
What habitat does Eriogonum umbellatum var. argus grow in?
Eriogonum umbellatum var. argus grows in Serpentine.
Related species
Other California species in the same genus, family, or bioregion.
- Eriogonum umbellatum var. bahiiforme — Bay buckwheat
- 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
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.