Maple Anthracnose: Brown Veinal Discoloration—Cultural and Chemical Control

Brown areas along leaf veins that crumble and die, often in symmetrical patterns, are classic maple anthracnose (caused by Discula spp.). Cool, wet springs favor it.

Symptoms

• Brown discoloration along veins, progressing toward petiole.
• Spore masses (like ground pepper) on leaf undersides in wet weather.
• Leaf curling, crinkling, premature defoliation.

Management

1. Rake and destroy fallen leaves before spring bud break.
2. Fertilize and water trees with significant defoliation: 10-10-10 at 1 lb/inch trunk diameter (fall and spring).
3. Fungicide for small/specimen trees: apply at bud break, then every 10–14 days until leaves mature. Labeled products: bordeaux mixture, Daconil 2787, Dithane T/O, Fore, Protect T/O, 3336, Halt.

The disease rarely kills mature trees.