Botanic Garden >> Gardening > >> Question and Answer >> Plant Diseases

White Spots on Maple Leaves: Cottony Cushion Scale

White Powdery Spots on Maple Leaf Undersides

These are likely cottony cushion scale insects. On large trees, spraying is impractical; natural predators usually keep them in check. Keep tree watered and avoid trunk damage.

Plant Diseases: Japanese Maple Honeydew and Sooty Mold: Aphid or Scale Infestation; Black Spots on Maple Leaves: Tar Spot Fungus—Rake Leaves, Reduce Inoculum, Tree Usually Fine; Tulip Tree White Spots and Sticky Leaves: Lichens, Honeydew, and Insect Control; Maple Leaf Underside White Spots: Galls or Aphids; White Powdery Spots on Maple Leaf Undersides: Likely Insects; White Spots on Red Maple: Superficial Fungus/Algae, Not Harmful; Maple Leaf Spots and Tulip Tree Trunk Holes: Two Separate Issues; Maple Leaf Galls: Insect-Caused Bumps on Autumn Blaze Maple; White Spots on 'King Crimson' Maple: Common Leaf Fungus, Easy Management; Japanese Maple Leaf Spots: Identifying and Managing Phyllosticta

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Bark Peeling and Leaf Spots on Young Maple: Decay Risk and Ants

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Maple Trunk White Spots: Harmless Lichens

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Late-Season Leaf Spots on Mature Maple: Cosmetic, Not Critical

Maple Leaf Spots: Phyllosticta and Tar Spot

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