Walnut Anthracnose
Gary W. Moorman, Professor of Plant Pathology
| Disease | Symptoms | Pathogen/Cause | Management |
|---|---|---|---|
| Anthracnose | Circular, brown spots with yellow halos form on the undersides of leaflets as the leaves reach full size. Leaflets yellow, brown, and fall prematurely, leaving trees very bare by August. Tiny, brown fungal fruiting structures form mostly along leaf veins on the undersides of leaves. | Gnomonia leptostyla | It is thought that little actual damage occurs to the tree since most of the growth has occurred before the leaves fall. However, repeated severe defoliation gradually weakens the tree. Fertilize the tree well to maintain good vigor. |
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