How to Treat Maple Anthracnose
- 1). Learn to identify the symptoms of anthracnose in maple trees. Symptoms particular to maple trees include purplish-brown areas along the veins of the leaves and light to dark brown areas between the leaf veins.
- 2). Keep the ground clear of maple leaves that have been infected with the anthracnose fungus by raking leaves frequently in the autumn. Compost or burn the leaves.
- 3). Prune the tree to remove dead twigs and thin the crown of the tree. This will improve air circulation and help the leaves dry more quickly. Dead twigs often harbor anthracnose and should be burned or buried to prevent reinfection of the tree.
- 4). Fertilize the tree in the autumn approximately one month after the first frost. If fertilizing in the springtime, do so approximately one month prior to the season's last frost. These dates can be based on yearly averages.
- 5). Spray a chemical fungicide containing mancozeb if you're having a difficult time controlling the disease through natural preventative measures. Spray the fungicide once when the buds appear and twice during leaf expansion. Refer to the product's instructions for precise application instructions.
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