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Japanese Walnut

Juglans ailantifolia

Juglandaceae · broadleaf deciduous tree · introduced

Last updated March 8, 2026

Data Coverage 2 of 6 dimensions
Site Data
Threats
Cultivars
Phenology
GDD Thresholds
Puget Sound

Quick Facts

Height
40–65 ft
Light
Full Sun
Hardiness
Zone Zones 5a–8b
Origin
Japan; introduced in 1860 A sport of the Japanese walnut,

Diseases (10)

Geosmithia morbida (vectored by Pityophthorus juglandis) Thousand Cankers Disease Xanthomonas arboricola pv. juglandis Walnut Blight Blackline virus Blackline Ophiognomonia leptostyla (syn. Gnomonia leptostyla) Anthracnose Blotch Colletotrichum acutatum complex (C Anthracnose Abiotic (juglone) Black Walnut Toxicity Rhizobium radiobacter (formerly Agrobacterium tumefaciens) Crown Gall Pseudomicrostroma juglandis (syn. Microstroma juglandis) Downy Leaf Spot Non-pathogenic Mosses and Lichens Phytophthora spp. (P Phytophthora Root Rot

Pests (7)

Pityophthorus juglandis Walnut Twig Beetle Rhagoletis completa Walnut Husk Fly Aceria erinea Walnut Blister Mite Chromaphis juglandicola Walnut Aphid Parthenolecanium corni European Fruit Lecanium Hyphantria cunea Fall webworm Nematode, Root-lesion

Also Known As

  • Heartnut

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