Quercus pacifica
Island scrub oak, Island Scrub Oak
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Family: Fagaceae · Type: Shrub / Tree · Native
Conservation status: CNPS 4.2
Quercus pacifica (Island scrub oak) is a native California shrub / tree in the Fagaceae family, recognized by small leaves with entire margins and Channel Islands distribution.
Island scrub oak is a California native shrub ranked 4.2 by CNPS, found on the Channel Islands including Santa Cruz, Santa Rosa, and Santa Catalina islands in chaparral, coastal scrub, oak woodland, and pine forest at elevations below 610 meters. Flowering from March to April, this plant produces small flowers in delicate clusters, developing distinctive acorn fruits. Growing as an evergreen shrub up to 2 meters tall with finely hairy, reddish-brown twigs that become gray with age, it forms dense, compact growth. Its leaves are obovate or oblong, 1.5 to 4 centimeters long, with a green upper surface and lighter green underside covered in minute stellate hairs, featuring entire or slightly wavy margins. The acorn cups are hemispheric and 8 to 20 millimeters wide, with moderately tubercled scales, producing ovoid nuts 20 to 30 millimeters long.
Identification and appearance
Key characters: 15 sympatric species; small leaves with entire margins and Channel Islands distribution
Habitat and range
Habitat: Slopes, ridges, canyons, chaparral, coastal scrub, oak woodland, pine forest
Elevation: < 610 m
California counties: Los Angeles, Santa Barbara, Santa Cruz
Bloom period
Quercus pacifica blooms Mar-Apr.
Conservation status
CNPS 4.2
How to tell it apart
vs Prunus: Quercus has acorns in cups; cherries/plums have fleshy round fruits.; vs Notholithocarpus: Quercus has drooping catkins; tanoak has upright flower spikes.; vs Rhamnus: Quercus has acorns; buckthorns have berry-like fruits.; vs Ceanothus: Quercus has acorns; California lilacs have small capsule fruits.; vs Platanus: Quercus has acorns; sycamores have hanging ball-shaped seed clusters.
Frequently asked questions
Is Quercus pacifica native to California?
Yes. Quercus pacifica is native to California (recorded as native).
When does Quercus pacifica bloom?
Quercus pacifica blooms Mar-Apr.
Where in California does Quercus pacifica grow?
Quercus pacifica occurs in Los Angeles, Santa Barbara, Santa Cruz, at elevations of < 610 m.
What plant family does Quercus pacifica belong to?
Quercus pacifica is in the Fagaceae family, genus Quercus.
Is Quercus pacifica rare or endangered?
Quercus pacifica carries California Rare Plant Rank 4.2, state rank S4.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
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.