Ionactis alpina
Lava-aster, crag-aster, Crag-Aster
(c) Tim Messick, some rights reserved (CC BY), uploaded by Tim Messick · licence
Family: Asteraceae · Type: Subshrub · Native
Ionactis alpina (Lava-aster) is a native California subshrub in the Asteraceae family, recognized by Great Basin genus reaching California in eastern Sierra Nevada; recently segregated from Aster.
Lava-aster is a California native perennial found in western Sierra Nevada, northern Sierra Nevada, and White and Inyo Mountains in dry, rocky places often associated with sagebrush at elevations of 1,300 to 3,000 meters. Flowering from May to July, this plant produces violet to purple ray flowers 7 to 12 millimeters long in solitary heads with distinctive lance-linear phyllaries. Growing with compact stems 4 to 12 centimeters tall that are slightly hairy, it forms a fibrous-rooted caudex. Its leaves are narrow and firm, measuring 0.3 to 1.2 centimeters long, oblanceolate to elliptic, and densely covered in short hairs. The plant's delicate violet rays and compact growth make it a distinctive alpine wildflower adapted to high-elevation rocky environments.
Identification and appearance
Key characters: Great Basin genus reaching California in eastern Sierra Nevada; recently segregated from Aster
Habitat and range
Habitat: Dry, rocky places, often with sagebrush
Elevation: 1300-3000 m
California counties: Mono, Modoc
Outside California: to eastern Oregon, Wyoming, Nevada
Bloom period
Ionactis alpina blooms May-Jul.
How to tell it apart
vs Dieteria: Ionactis has solitary heads on stems; Dieteria heads often clustered or branched.; vs Chloracantha: Ionactis has oblong rays and yellow disks; check specific Chloracantha traits.; vs Eucephalus: Ionactis in Great Basin sagebrush; Eucephalus in mountain forests.; vs Sericocarpus: Ionactis has yellow disk flowers; Sericocarpus has white disk flowers.; vs Erigeron: Ionactis has 1-16 oblong rays; Erigeron has numerous narrow thread-like rays.
Frequently asked questions
Is Ionactis alpina native to California?
Yes. Ionactis alpina is native to California (recorded as native).
When does Ionactis alpina bloom?
Ionactis alpina blooms May-Jul.
Where in California does Ionactis alpina grow?
Ionactis alpina occurs in Mono, Modoc, at elevations of 1300-3000 m.
What plant family does Ionactis alpina belong to?
Ionactis alpina is in the Asteraceae family, genus Ionactis.
What habitat does Ionactis alpina grow in?
Ionactis alpina grows in Dry, rocky places, often with sagebrush.
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.