Eriogonum microtheca var. ambiguum
Yellow-flowered wild buckwheat, Yellow-Flowered Wild Buckwheat
Photo: parent species Eriogonum microtheca · (c) Jared Shorma, some rights reserved (CC BY) · licence
Family: Polygonaceae · Type: Shrub · Native
Eriogonum microtheca var. ambiguum (Yellow-flowered wild buckwheat) is a native California shrub in the Polygonaceae family, recognized by . Key features: bright yellow flowers distinguish from other microtheca varieties.
Yellow-flowered wild buckwheat is a California native shrub found in the eastern Sierra Nevada and Great Basin in sandy, gravelly, or rocky habitats at elevations of 1,900 to 3,300 meters. Flowering from July to September, this plant produces distinctive yellow flowers in compact clusters 1 to 5 centimeters long. Growing as a low subshrub 0.5 to 5 decimeters tall with a spread of 1 to 8 decimeters, it features hairy stems and a dense growth habit. Its small leaves are 0.8 to 2.5 centimeters long, with soft tomentose undersides and a narrow width of 0.3 to 0.6 centimeters. The fruit is small, measuring 1.5 to 2 millimeters in length.
Identification and appearance
Key characters: 102 sympatric species. Key features: bright yellow flowers distinguish from other microtheca varieties
Habitat and range
Habitat: Common. Sand, gravel or rocks
Elevation: (1100)1900-3300 m
Outside California: to southeastern Oregon, southwestern Idaho, western Nevada
Bloom period
Eriogonum microtheca var. ambiguum blooms Jul-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 microtheca var. ambiguum native to California?
Yes. Eriogonum microtheca var. ambiguum is native to California (recorded as native).
When does Eriogonum microtheca var. ambiguum bloom?
Eriogonum microtheca var. ambiguum blooms Jul-Sep.
What plant family does Eriogonum microtheca var. ambiguum belong to?
Eriogonum microtheca var. ambiguum is in the Polygonaceae family, genus Eriogonum.
What habitat does Eriogonum microtheca var. ambiguum grow in?
Eriogonum microtheca var. ambiguum grows in Common. Sand, gravel or rocks.
Related species
Other California species in the same genus, family, or bioregion.
- Eriogonum microtheca var. corymbosoides — San bernardino wild buckwheat
- Eriogonum microtheca var. johnstonii — Johnston's buckwheat
- Eriogonum microtheca var. lacus-ursi — Bear lake buckwheat
- Eriogonum microtheca var. lapidicola — Inyo mountains buckwheat
- Eriogonum microtheca var. laxiflorum — Great basin wild buckwheat
- Eriogonum microtheca var. panamintense — Panamint mountains buckwheat
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.