California Buckthorn

Frangula californica

Native to:
Mexico, United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Rhamnaceae
Genus:
Frangula
Species:
Frangula californica
USDA Symbol:
FRCA12

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Shrub , Tree
Height:
450 cm
Light Requirements:
Full Sun
Drought Tolerance:
High
Bloom Months:
mar,apr,may,jun,jul
Bloom Colors:
green, yellow
Landscaping Shrub:
Yes

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)
Caterpillars:
★★★☆☆ Recorded caterpillar host plant (HOSTS Database)

Host Plant for Caterpillars

Aristotelia rhamnina, Ceanothus Silkmoth (Hyalophora euryalus), Clepsis fucana, Elegant Sheep Moth (Hemileuca eglanterina), Epinotia lomonana, Holcocera sp. B, Microcalyptris punctulata, orange tortrix moth (Argyrotaenia franciscana), Orgyia cana (Orgyia cana), Saturnia homogena, Sorhagenia nimbosa, Stigmella diffasciae, Stigmella sp. B, Western tussock moth (Orgyia vetusta), Gray Hairstreak (Strymon melinus), Pale Swallowtail (Papilio eurymedon)

Reported Fauna Sightings

Bees: Yellow-faced bumble bee (Bombus vosnesenskii) Moths:Sorhagenia nimbosus

Garden & Ecology Notes

Wildlife Value:
birds, butterflies, bees
Deer Resistant:
Yes
Fire Ecology:
Fire adapted — tolerates or benefits from fire
Fire Notes:
Resprouts vigorously from the root crown following fire; common in chaparral and coastal scrub fire regimes.

Soil Requirements

Soil Type:
well-drained, rocky or sandy soil
pH:
5.5 - 7.5 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
adapted to chaparral and woodland habitats

Propagation & Germination

Stratification:
Cold/moist stratification required — 60–90 days
Germination Time:
14–60 days
Notes:
Fresh seed germinates best; cold stratification improves germination rates for stored seed.

The above propagation data sourced from Claude AI

Pre-treatment: For seeds: Soak in fresh water for 24 hours, then place in a plastic ziplock bag with an equal amount of barely moistened perlite. Stratify for 2 to 3 months in a refrigerator, checking every 2 weeks for moisture content and mold development. For cuttings: Dip in a mild bleach solution for 30 seconds, make a 45 degree angle cut just below last node at the base of the cutting, leaving one leaf above the top node. Treat with Hormex (3000 ppm IBA) rooting powder.

Establishment: Seeds are collected between July 1st and October 1st, while hardwood cuttings are collected between November 1st and January 31st. F. californica is found in sandy and rocky places along the coast, below 3,500 feet elevation; from southern Oregon to Orange County, California.

Source: npn.rngr.net