Maple: Maple bladdergall mite

Biology

The maple bladdergall mite is a tiny mite that feeds on the underside of leaves. The mites overwinter in cracks and under bark scales and begin feeding in spring. Infested leaves initially develop small depressions which soon grow into brilliant red galls 1/8″ to 1/4″ in length. Later in the season, the galls may turn green or black. Mite activity typically stops by around July. Silver and red maples are particularly susceptible to bladdergall mites. Severe infestations may cause leaves to become somewhat distorted. Although an aesthetic concern, bladdergalls are seldom harmful to the trees.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

• Hand-pick severely infested or distorted leaves to improve appearance of small trees.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

• None recommended