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California Walnut

Juglans californica

Juglandaceae · broadleaf · introduced

Quick Facts

Height
40 ft
Growth Rate
Medium
Light
Full Sun
Soil
Moist
Water
Moderate
Hardiness
Zone Zones 8a–8b
Fall Color
Brown, yellow
Origin
southern California, approximately from Santa Barbara to

Diseases (10)

Geosmithia morbida (vectored by Pityophthorus juglandis) Thousand Cankers Disease
Walnut Blight
Blackline
Ophiognomonia leptostyla (syn. Gnomonia leptostyla) Anthracnose Blotch
Various species including Colletotrichum acutatum, C Anthracnose
Black Walnut Toxicity
Rhizobium radiobacter (formerly Agrobacterium tumefaciens) Crown Gall
Downy Leaf Spot
Mosses and Lichens
Phytophthora spp. (P Phytophthora Root Rot

Pests (7)

Walnut Twig Beetle
Walnut Husk Fly
Aceria erinea Walnut Blister Mite
Walnut Aphid
European Fruit Lecanium
Fall webworm
Nematode, Root-lesion

Also Known As

  • Southern California Walnut

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