Silver Maple - 100 Most Common North American Trees

Pest information courtesy of USFS Fact Sheets:

Insects: Leaf stalk borer and petiole-borer are insects that bore into the leaf stalk just below the leaf blade. The leaf stalk shrivels, turns black, and the leaf blade falls off.
Gall mites stimulate the formation of growths or galls on the leaves. The galls are small but can be so numerous that individual leaves curl up. The most common gall is bladder gall mite found on silver maple.
Crimson erineum mite is usually found on silver maple and causes the formation of red fuzzy patches on the lower leaf surfaces. The problem is not serious so control measures are not suggested.
Aphids infest maples, usually Norway Maple, and may be numerous at times. High populations can cause leaf drop.
Scales are an occasional problem on maples. Perhaps the most common is cottony maple scale. The insect forms a cottony mass on the lower sides of branches.

Diseases: Anthracnose is more of a problem in rainy seasons. The disease resembles, and may be confused with, a physiological problem called scorch. The disease causes light brown or tan areas on the leaves.
Tar spot and a variety of leaf spots cause some concern among homeowners but are rarely serious enough for control.

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