Eurybia integrifolia
Thickstem aster
(c) My-Lan Le, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Subshrub · Native
Eurybia integrifolia (Thickstem aster) is a native California subshrub in the Asteraceae family, recognized by . Key features: basal leaves present at flowering, spreading phyllary tips, dense glands.
Thickstem aster is a California native perennial found in the Klamath Ranges, Cascade Range, Sierra Nevada, and Warner Mountains in dry meadows and open forest at elevations of 1,600 to 3,200 meters. Flowering from July to September, this plant produces violet-purple ray flowers 10 to 15 millimeters long in distinctive elongate clusters. Growing with erect stems 15 to 70 centimeters tall that are glandular in the upper portions, it develops from short, somewhat woody rhizomes. Its leaves range from long-petioled basal leaves that are lance-ovate to obovate to cauline leaves that are lanceolate and clasping at the base, with most leaves remaining green and glabrous to slightly hairy. The plant's inflorescence features phyllaries with spreading tips that are densely glandular, with outer phyllaries green to the base and inner phyllaries green at the tip and subtly purple-tinged.
Identification and appearance
Key characters: 2 sympatric species. Key features: basal leaves present at flowering, spreading phyllary tips, dense glands
Habitat and range
Habitat: dry meadows, open forest
Elevation: 1600-3200 m
California counties: Tulare, Mono, Modoc, Fresno, Amador, Lassen, Calaveras, Madera, Shasta, Tehama, Mariposa, Alpine, El Dorado, Plumas, Nevada, Sierra, Placer, Tuolumne, Siskiyou, Butte
Outside California: to Washington, Montana, Wyoming, Utah
Bloom period
Eurybia integrifolia blooms Jul-Sep.
How to tell it apart
vs Symphyotrichum: Symphyotrichum has all-green bracts; Eurybia has two-toned bracts with white bases; vs Aster: Aster typically refers to Symphyotrichum; check if bracts have white bases for Eurybia; vs Erigeron: Erigeron has many thread-like rays; Eurybia has fewer broader rays and two-toned bracts; vs Chaetopappa: Chaetopappa is a tiny 2-6 inch desert plant; Eurybia is robust and forest-dwelling; vs Almutaster: Almutaster has all-green bracts and grows in alkaline meadows; Eurybia has two-toned bracts
Frequently asked questions
Is Eurybia integrifolia native to California?
Yes. Eurybia integrifolia is native to California (recorded as native).
When does Eurybia integrifolia bloom?
Eurybia integrifolia blooms Jul-Sep.
Where in California does Eurybia integrifolia grow?
Eurybia integrifolia occurs in Tulare, Mono, Modoc, Fresno, Amador, Lassen, Calaveras, Madera and other counties, at elevations of 1600-3200 m.
What plant family does Eurybia integrifolia belong to?
Eurybia integrifolia is in the Asteraceae family, genus Eurybia.
What habitat does Eurybia integrifolia grow in?
Eurybia integrifolia grows in dry meadows, open forest.
Related species
Other California species in the same genus, family, or bioregion.
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.