This article is a list of diseases of black walnuts (Juglans nigra).
| Fungal diseases | |
|---|---|
| Anthracnose | Gnomonia leptostyla Marssonina juglandis [anamorph] |
| Cylindrocladium root rot | Cylindrocladium scoparium Calonectria kyotensis [teleomorph] Cylindrocladiella parva Cylindrocladium parvum |
| Fusarium canker | Fusarium sporotrichioides Fusarium solani Fusarium lateritium Fusarium oxysporum |
| Leaf spot | Mycosphaerella juglandis Cylindrosporium juglandis [anamorph] |
| Nectria canker | Nectria galligena |
| Phytophthora root rot | Phytophthora citricola Phytophthora cinnamomi |
| Seedling shoot dieback | Phomopsis arnoldiae Phomopsis elaeagni |
| Thousand cankers disease | Geosmithia fungus |
| Walnut bunch | Phytoplasma organism |
| White mold | Microstroma juglandis |
| White trunk rot | Phellinus igniarius |
| Wood decay | Schizophyllum commune Hypochnicium vellereum Trametes versicolor Phellinus gilvus Peniophora cinerea Hericium coralloides |
| Zonate leaf spot | Grovesinia pyramidalis |
| Nematodes, parasitic | |
|---|---|
| Lesion nematodes | Pratylenchus musicola |
| Root-knot nematodes | Meloidogyne spp. |