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Maple Gall Mites: Cosmetic, No Treatment Needed

Red fungus-like material on sugar maple leaf undersides (lower branches), some leaf holes from chewing.

Diagnosis

Gall mites—microscopic, cause red galls on leaf undersides. Life cycle makes control difficult after eggs covered by leaf cells. Population varies yearly—may disappear next year.

Significance

No real health impact on tree growth. Don't worry. Monitor—may not recur.

Plant Diseases: Sugar Maple Northern Tooth Fungus: Emergency Branch Removal Protocol; Orange Fungus at Base of Japanese Maple: Mulch Decay, Not Tree Disease; Red Maple Borer Infestation: Sap Flow and Bud Failure; Maple Trees Hit by Truck: Stabilize, Mulch, Document for Insurance; Maple Tree Planting for Town Bicentennial: Disease Risks Manageable; Hypoxylon Canker and Root Stress Killing Mature Trees in Wet Soil; Caring for Aging Maple Trees: Addressing Bark Loss, Mushrooms, and Lichens; Red Maple Bark Splitting: Sunscald/Frost Cracks; Sycamore and Silver Maple Decline in Georgia Drought: Wait for Spring; Choosing the Right Maple Tree for Your Yard: Root Systems and Fall Color

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