Eriogonum umbellatum var. torreyanum
Donner pass buckwheat, Donner Pass Buckwheat
Photo: parent species Eriogonum umbellatum · Photo by Chez Brungraber
Family: Polygonaceae · Type: Subshrub · Native
Conservation status: CNPS 1B.2
Eriogonum umbellatum var. torreyanum (Donner pass buckwheat) is a native California subshrub in the Polygonaceae family, recognized by glabrous habit, whorled bracts, and high elevation.
Donner pass buckwheat is a rare (CNPS 1B.2) California native perennial found in northern Sierra Nevada Mountains in Sierra, Nevada, and Placer counties, growing in sandy or gravelly habitats at elevations of 2,100 to 2,400 meters. Flowering from July to September, this plant produces distinctive yellow flowers in compact umbels. Growing as a low mat formation 4 to 8 meters in diameter with erect stems 10 to 20 centimeters tall, it forms a tight ground-hugging cluster. Its leaves are glabrous, blade-shaped, 1 to 3 centimeters long and 1 to 2 centimeters wide, creating a dense green base for the bright yellow flower clusters. The plant forms neat, compact mats with multiple flowering stems emerging from a single root system.
Identification and appearance
Key characters: 67 sympatric species; distinguished by glabrous habit, whorled bracts, and high elevation
Habitat and range
Habitat: Sand or gravel
Elevation: (1800)2100-2400 m
California counties: Nevada, Placer, Sierra, Butte, Modoc
Bloom period
Eriogonum umbellatum var. torreyanum blooms Jul-Sep.
Conservation status
CNPS 1B.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. torreyanum native to California?
Yes. Eriogonum umbellatum var. torreyanum is native to California (recorded as native).
When does Eriogonum umbellatum var. torreyanum bloom?
Eriogonum umbellatum var. torreyanum blooms Jul-Sep.
Where in California does Eriogonum umbellatum var. torreyanum grow?
Eriogonum umbellatum var. torreyanum occurs in Nevada, Placer, Sierra, Butte, Modoc, at elevations of (1800)2100-2400 m.
What plant family does Eriogonum umbellatum var. torreyanum belong to?
Eriogonum umbellatum var. torreyanum is in the Polygonaceae family, genus Eriogonum.
Is Eriogonum umbellatum var. torreyanum rare or endangered?
Eriogonum umbellatum var. torreyanum carries California Rare Plant Rank 1B.2, state rank S2.
Related species
Other California species in the same genus, family, or bioregion.
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.