Southern California Walnut
Juglans californica
- Native to:
- United States
iNaturalist: © johnreiss (iNaturalist #18598475)
Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Juglandaceae
- Genus:
- Juglans
- Species:
- Juglans californica
- USDA Symbol:
- JUCA
Growth Characteristics
- Life Cycle:
- Perennial
- Growth Habit:
- Shrub , Tree
- Height:
- 1500 cm
- Light Requirements:
- Part Shade
- Drought Tolerance:
- High
- Bloom Months:
- apr,may
- Bloom Colors:
- greenish-yellow
Wildlife Benefits
- 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
Fall webworm (Hyphantria cunea), Leconte's haploa (Haploa lecontei), Semiothisa aspirata, Spilosoma vestalis, Western tussock moth (Orgyia vetusta)
Reported Fauna Sightings
Moths:Stigmella longisacca
Garden & Ecology Notes
- Wildlife Value:
- birds, small mammals
- Fall Color:
- yellow
- Fire Ecology:
- Fire adapted — tolerates or benefits from fire
- Fire Notes:
- Mature trees can resprout from the root crown after fire; seedlings establish in post-fire conditions.
Soil Requirements
- Soil Type:
- well-drained, sandy loam soil
- pH:
- 6.0 - 7.5 (slightly acidic to neutral)
- Drainage:
- excellent drainage required
- Moisture:
- dry to moderate
- Notes:
- prefers alluvial soils in native habitat
Propagation & Germination
- Stratification:
- Cold/moist stratification required — 60–120 days
- Germination Time:
- 30–90 days
- Notes:
- Seeds require cold stratification for 2-4 months; germination occurs in spring.
Pre-treatment: Cold-moist stratification for 30 days at 1–5°C (34–41°F).; then Cold-moist stratification for 90 days.
Source: Claude AI
Where to Buy
Nationwide Seller
- Sheffield's Seed (seeds)