When the leaves are almost fully grown light brown areas appear along the veins. Later the infected leaves fall off and trees may be nearly completely defoliated. The disease can cause twig and branch cankers. The trees send out a second crop of leaves but repeated attacks can lower tree vigor. Use a properly labeled copper fungicide at bud break, with additional sprays at 10 day intervals as long as the average temperature remains below 55 degrees.
Fertilization helps trees withstand repeated defoliation.
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