Frangula purshiana subsp. annonifolia
Photo: parent species Frangula purshiana · no rights reserved · CC0
Family: Rhamnaceae · Type: Shrub · Native
Frangula purshiana subsp. annonifolia is a native California shrub in the Rhamnaceae family, recognized by tapered leaf bases and non-serpentine habitat.
Cascara is a California native shrub found in the Klamath Ranges, Cascade Range, and northern Sierra Nevada in conifer forest edges and streamsides at elevations below 2,000 meters. Flowering from March to June, this plant produces small white to cream-colored flowers in delicate clusters. Growing up to 5 meters tall with distinctive red to brown twigs, it forms an open, spreading shrub structure. Its leaves are thin and green, with petioles 5 to 25 millimeters long, featuring irregularly toothed margins and an obtuse to truncate leaf tip. The foliage ranges from glabrous to sparsely hairy, with a delicate tapered base.
Identification and appearance
Key characters: 11 sympatric species; key features are tapered leaf bases and non-serpentine habitat
Habitat and range
Habitat: Conifer forest edges, streamsides, non-serpentine
Elevation: < 2000 m
Outside California: southern Oregon
Bloom period
Frangula purshiana subsp. annonifolia blooms Mar-Jun.
How to tell it apart
vs Heteromeles: Frangula has simple leaves and naked buds; Heteromeles has toothed leaves and scaly buds.; vs Prunus: Frangula berries turn from red to black; Prunus fruits are uniform colored when ripe.; vs Rhamnus: Frangula buds are naked (no scales); Rhamnus buds have protective scales.; vs Quercus: Frangula has opposite or alternate smooth leaves; Quercus has spiral lobed or toothed leaves.; vs Umbellularia: Frangula leaves lack strong aroma; Umbellularia leaves smell strongly spicy when crushed.
Frequently asked questions
Is Frangula purshiana subsp. annonifolia native to California?
Yes. Frangula purshiana subsp. annonifolia is native to California (recorded as native).
When does Frangula purshiana subsp. annonifolia bloom?
Frangula purshiana subsp. annonifolia blooms Mar-Jun.
What plant family does Frangula purshiana subsp. annonifolia belong to?
Frangula purshiana subsp. annonifolia is in the Rhamnaceae family, genus Frangula.
What habitat does Frangula purshiana subsp. annonifolia grow in?
Frangula purshiana subsp. annonifolia grows in Conifer forest edges, streamsides, non-serpentine.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · 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.