Eriastrum diffusum subsp. diffusum
Spreading woolly-star
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Family: Polemoniaceae · Type: Annual · Native
Eriastrum diffusum subsp. diffusum (Spreading woolly-star) is a native California annual in the Polemoniaceae family, recognized by flower size and color pattern distinguish from subspecies coachellae.
Spreading woolly-star is a native annual found in desert scrub, arid woodland, and grassland habitats across washes, floodplains, and hillsides at elevations of 100 to 1,800 meters. Flowering from April to May, this delicate plant produces white flowers with yellow or yellow-spotted throats, blue to cream-colored corolla lobes, and intricate blue to white blossoms. Growing with erect to spreading stems 1 to 25 centimeters tall, the plant develops woolly stems that become less hairy with age. Its leaves are woolly, measuring 9 to 26 millimeters long, with zero to five subtle lobes that create a soft, textured appearance. The small fruit capsules are approximately 2.7 to 3 millimeters long, containing tan to light brown angular seeds.
Identification and appearance
Key characters: 15 sympatric species - flower size and color pattern distinguish from subspecies coachellae
Habitat and range
Habitat: Washes, floodplains, flats, hillsides, alluvial fans, disturbed areas, in desert scrub, arid woodland, grassland
Elevation: 100-1800 m
Outside California: to Colorado, Texas, northwest Mexico
Bloom period
Eriastrum diffusum subsp. diffusum blooms Apr-May.
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 diffusum subsp. diffusum native to California?
Yes. Eriastrum diffusum subsp. diffusum is native to California (recorded as native).
When does Eriastrum diffusum subsp. diffusum bloom?
Eriastrum diffusum subsp. diffusum blooms Apr-May.
What plant family does Eriastrum diffusum subsp. diffusum belong to?
Eriastrum diffusum subsp. diffusum is in the Polemoniaceae family, genus Eriastrum.
What habitat does Eriastrum diffusum subsp. diffusum grow in?
Eriastrum diffusum subsp. diffusum grows in Washes, floodplains, flats, hillsides, alluvial fans, disturbed areas, in desert scrub, arid woodland, grassland.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos
Last updated 2026-10-06
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.