Maple Spindle Gall Mites: Cosmetic Only

Spike-like growths on maple leaves are maple spindle galls caused by microscopic eriophyid mites (Vasates aceris-crumena). Unsightly but harmless.

Gall Biology

• 1/5" long, spindle-shaped, on upper leaf surface
• Mites overwinter under bark scales near buds
• Spring activity causes gall formation on new leaves
• Abundance varies wildly year to year

Management Philosophy

• No treatment needed—galls don't harm tree health
• Only aesthetic concern for specimen trees
• Focus on tree vigor: water, mulch, fertilize as needed
• Insecticides kill beneficial mites, often worsen problem

Your Vermont maples are fine. This is normal maple-mite ecology. Enjoy the textural curiosity—it's a sign of biodiversity.