Buckbrush

Ceanothus cuneatus

Native to:
Mexican Pacific Is., Mexico, United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Rhamnaceae
Genus:
Ceanothus
Species:
Ceanothus cuneatus
USDA Symbol:
CECU

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Shrub
Height:
250 cm
Light Requirements:
Full Sun
Drought Tolerance:
High
Bloom Months:
mar,apr,may
Bloom Colors:
white, cream
Landscaping Shrub:
Yes

Wildlife Benefits

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

Keystone Species Ranking

Caterpillar Keystone:
★★★★☆ Butterfly & moth species supported by this genus (NWF)

Host Plant for Caterpillars

Aristotelia adceanotha, fruit-tree leafroller (Archips argyrospila), Mendocino saturnia moth (Saturnia mendocino), Microcalyptris punctulata, Pandemis leafroller (Pandemis pyrusana), Saturnia albofasciata, sulphur moth (Hesperumia sulphuraria), Walter's saturnia moth (Saturnia walterorum), Western tent caterpillar (Malacosoma californica), Brown Elfin (Incisalia augustinus), California hairstreak (Satyrium californicum), California tortoiseshell (Nymphalis californica), Hedgerow Hairstreak (Satyrium saepium), Pale Swallowtail (Papilio eurymedon)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies, birds, deer browse
Fragrant:
Yes
Fire Ecology:
Fire adapted — tolerates or benefits from fire
Fire Notes:
Resprouts vigorously from root crown after fire. Part of chaparral fire ecology with moderate fire return intervals.

Soil Requirements

Soil Type:
sandy, well-drained, nutrient-poor soil
pH:
5.5 - 7.5 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
Thrives in chaparral and coastal scrub habitats

Propagation & Germination

Stratification:
Cold/moist stratification required — 60–90 days
Scarification:
Seed coat scarification required before sowing
Germination Time:
30–90 days
Notes:
Hot water treatment or scarification followed by cold stratification improves germination. Seeds may benefit from smoke or fire cues.

The above propagation data sourced from Claude AI

Pre-treatment: Seeds are placed in fine mesh bags, soaked for 10 seconds in boiling water and then immediately transferred in cold water. Seeds are then placed into a 1% hydrogen peroxide (3:1 water/3% hydrogen peroxide) soak for 24 hours, rinsed, and placed in water for an additional 4 hours. Seeds are sown into trays filled with stabilized medium plugs (Q-plugs). Trays are sealed inside plastic bags and placed into refrigeration at 1 to 3 °C for 90 days. Trays are checked weekly and kept moist throughout the stratification period. If mold is evident, trays should be treated with 1% hydrogen peroxide.

Establishment: Ceanothus cordulatus, also known as whitethorn ceanothus or white ceanothus, is generally found in Oregon, California, Nevada and within mattoral vegetation association of California. There is a variation in the pre-planting propagule treatments across the protocols, with one suggesting that seeds germinate at greenhouse temperatures without any specific treatment.

Source: npn.rngr.net