Eriastrum ertterae
Lime ridge woolly-star, lime ridge eriastrum, ertter's woolly-star
(c) Trevor Van Loon, some rights reserved (CC BY) · licence
Family: Polemoniaceae · Type: Herb · Native
Conservation status: CNPS 1B.1
Eriastrum ertterae (Lime ridge woolly-star) is a native California herb in the Polemoniaceae family.
Lime ridge woolly-star is a rare (CNPS 1B.1) California native annual found in northern and central Coast Ranges Interior in open areas, firebreaks, chaparral, and oak woodland at elevations of 190 to 280 meters. Flowering in June, this plant produces delicate white to very pale blue flowers with occasional lavender streaks, featuring a narrowly funnel-shaped corolla about 6 millimeters long. Growing 1.5 to 20 centimeters tall with erect stems that are simple or branched above the base, it develops thread-like to linear leaves that begin woolly when young and become nearly smooth with age. Its leaves are typically 9 to 29 millimeters long, sometimes with 3 lobes at the base, and the plant forms terminal flower heads containing 3 to 9 blossoms. The fruit is a small tan capsule approximately 3 to 4 millimeters long, containing 2 to 4 seeds per chamber.
Identification and appearance
Key characters: Geographically isolated from all congeners
Habitat and range
Habitat: Open areas, firebreaks, in chaparral, oak woodland
Elevation: 190-280 m
Bloom period
Eriastrum ertterae blooms Jun.
Conservation status
CNPS 1B.1
How to tell it apart
vs Navarretia: Eriastrum has fluffy white woolly hairs; Navarretia has spine-tipped bracts and leaves without woolly hairs.; vs Gilia: Eriastrum flower clusters are densely woolly-hairy; Gilia flower clusters lack woolly hairs.; vs Loeseliastrum: Eriastrum has woolly tufted hairs and radial flowers; Loeseliastrum has simple hairs and bilateral flowers.; vs Langloisia: Eriastrum has woolly tufted white hairs; Langloisia has stiff branched bristly hairs.; vs Petalonyx: Eriastrum has opposite lobed leaves in Polemoniaceae; Petalonyx has alternate simple leaves in Loasaceae.
Frequently asked questions
Is Eriastrum ertterae native to California?
Yes. Eriastrum ertterae is native to California (recorded as native).
When does Eriastrum ertterae bloom?
Eriastrum ertterae blooms Jun.
What plant family does Eriastrum ertterae belong to?
Eriastrum ertterae is in the Polemoniaceae family, genus Eriastrum.
Is Eriastrum ertterae rare or endangered?
Eriastrum ertterae carries California Rare Plant Rank 1B.1, state rank S1.
What habitat does Eriastrum ertterae grow in?
Eriastrum ertterae grows in Open areas, firebreaks, in chaparral, oak woodland.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos · CDFW CNDDB
Last updated 2026-10-08
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.