Anthracnoses (fungi)
Leaf spots due to maple anthracnose. Center of spots may fall out.	In wet springs and falls, irregular blotches on leaves. May vary widely in color. Blighting phase of maple anthracnose.	Refer to the PDC Fact Sheet "Leaf Spot Diseases of Shade Trees and Ornamentals" for more information. Use azoxystrobin (Japanese and sugar maple only), chlorothalonil, copper products, mancozeb, maneb, myclobutanil, propiconazole, sulfur, thiophanate-methyl or triadimefon.
Leaf scorch	Leaves brown on margins and/or in interveinal areas. Inter- veinal areas may become tattered.	See leaf scorch in General Problems table.
Maple decline (complex of insects, diseases and stress) (See MU publication G 5200)	Trees decline in vigor over several seasons. Foliage is thin and weak. Leaves turn yellow, wither and fall early. Early fall color. Symptoms produced by inability of root system to supply enough water and nutrients to support above-ground parts.	Remove all dead and dying branches. Fertilize with high-phosphorus and low- nitrogen compounds to stimulate root growth. Water during periods of moisture stress. If specific disease or insect problems are recognized, treat each specific problem appropriately.
Phyllosticta leaf spot Macrophoma leaf spot (fungi)	These fungal leaf spots are small and circular. They do not typically cause defoliation.	Ignore these leaf spots. Refer to the PDC Fact Sheet "Leaf Spot Diseases of Shade Trees and Ornamentals" for more information.
Tar spot (fungus)	Small, shiny, raised black spots surrounded by a yellow halo appear on upper surface.	Ignore these leaf spots. Refer to the PDC Fact Sheet "Leaf Spot Diseases of Shade Trees and Ornamentals" for more information.
Verticillium wilt (fungus)
	Very destructive. Leaves suddenly discolor and wilt on one or more limbs in mid-summer, usually. Olive-green to brown streaks in sapwood.	Cut and remove severely affected trees. If only 1 to 6 dead or wilted limbs, prune affected parts. Dip pruning tools in 70% alcohol or 10% household bleach between cuts. No chemical control suggested. Fertilize in early spring to encourage growth. Avoid replanting on same site or replant only with resistant species.
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