Eriogonum umbellatum var. glaberrimum
Warner mountains buckwheat, Warner Mountains Buckwheat
Photo: parent species Eriogonum umbellatum · Photo by Chez Brungraber
Family: Polygonaceae · Type: Subshrub · Native
Conservation status: CNPS 1B.3
Eriogonum umbellatum var. glaberrimum (Warner mountains buckwheat) is a native California subshrub in the Polygonaceae family, recognized by completely glabrous appearance and pale flowers very distinctive.
Warner mountains buckwheat is a rare (CNPS 1B.3) California native perennial found in the Warner Mountains in sandy or gravelly habitats at elevations of 1,600 to 2,300 meters. Flowering from July to September, this plant produces cream to white flowers in delicate umbel clusters. Growing as a low-spreading mat 3 to 8 meters in diameter with smooth, glabrous stems 10 to 20 centimeters tall, it forms a compact ground-hugging form. Its leaves are small and glabrous, measuring 1 to 2 centimeters long and 0.3 to 1 centimeter wide, creating a fine-textured green groundcover. The plant's involucre tubes are 4 to 5 millimeters long with distinctive teeth 1 to 3.5 millimeters in length.
Identification and appearance
Key characters: 37 sympatric species; completely glabrous appearance and pale flowers very distinctive
Habitat and range
Habitat: Sand or gravel
Elevation: 1600-2300 m
Outside California: south-central Oregon
Bloom period
Eriogonum umbellatum var. glaberrimum blooms Jul-Sep.
Conservation status
CNPS 1B.3
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. glaberrimum native to California?
Yes. Eriogonum umbellatum var. glaberrimum is native to California (recorded as native).
When does Eriogonum umbellatum var. glaberrimum bloom?
Eriogonum umbellatum var. glaberrimum blooms Jul-Sep.
What plant family does Eriogonum umbellatum var. glaberrimum belong to?
Eriogonum umbellatum var. glaberrimum is in the Polygonaceae family, genus Eriogonum.
Is Eriogonum umbellatum var. glaberrimum rare or endangered?
Eriogonum umbellatum var. glaberrimum carries California Rare Plant Rank 1B.3, state rank S2.
What habitat does Eriogonum umbellatum var. glaberrimum grow in?
Eriogonum umbellatum var. glaberrimum grows in Sand or gravel.
Related species
Other California species in the same genus, family, or bioregion.
- Eriogonum umbellatum var. goodmanii — Goodman's sulphur flower
- Eriogonum umbellatum var. humistratum — Mount eddy buckwheat
- Eriogonum umbellatum var. juniporinum — Juniper sulphur-flowered buckwheat
- Eriogonum umbellatum var. lautum — Scott valley buckwheat
- Eriogonum umbellatum var. minus — Alpine sulphur-flowered buckwheat
- Eriogonum umbellatum var. modocense — Modoc sulphur flower
Sources: Jepson eFlora · 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.