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Red Sunset Maple Raised Red Spots: Insect Galls

Newly planted Red Sunset maple in Chicago suburb has raised hard red spots on leaves.

Diagnosis

Spots are insect galls—cosmetic, not harmful, may recur yearly.

Treatment

Apply Bayer Advanced Tree & Shrub Insecticide (imidacloprid soil drench) next spring for best uptake. Systemic, kills gall-makers, protects 1 year.

Plant Diseases: Red Sunset Maple Leaves Turning Brown: Causes and Solutions; Sunset Maple Bark Splitting and Leaf Spots: Need Photos for Diagnosis; Red Sunset Maple Top Leaf Drop: Root System Lag; Phyllosticta Leaf Spot on Red Sunset Maple: Spring Fungicide and Fertilizer; Troubleshooting a Struggling Sunset Maple: Water, Nutrients, and Herbicide Risks; Red Sunset Maple Seedlings: Hybrid Genetics Explained; Red Maple Borer Treatment: Insecticide Options and Application; Red Maple Borer Holes: Insecticide Treatment and Monitoring; Red Maple 'Red Sunset' (Acer rubrum): The Gold Standard for Fall Color; Seedless Red Maples: Why Your Tree Lacks Helicopters

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