Pest information courtesy of USFS Fact Sheets:
Pests: Aphids will suck the sap from Sycamore. Heavy infestations deposit honeydew on lower leaves and objects beneath the tree, such as cars and sidewalks. These infestations usually do no real harm to the tree.
Sycamore lace bugs feed on the undersides of the leaves causing a stippled appearance. The insects leave black flecks on the lower leaf surface, and cause premature defoliation in late summer and early fall.
Diseases: Some fungi cause leaf spots but are usually not serious.
Anthracnose causes early symptoms on young leaves resembling frost injury. 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 fungicide accordingto the latest recommendations.
Fertilization helps trees withstand repeated defoliation. Powdery mildew causes a white fuzz on the tops of leaves and distorts leaves. A bacterial leaf scorch can kill the tree in several growing seasons, and can cause significant tree losses. Leaves appear scorched, become crisp, and curl up as they turn a reddish-brown. Stress cankers form on limbs of trees stressed with drought.
Sycamore Anthracnose Disease
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