Hackberry - 100 Most Common North American Trees

Pest information courtesy of USFS Fact Sheets
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Pests: The most common insect on Hackberry causes the Hackberry nipple gall. A pouch or gall forms on the lower leaf surface in response to feeding. There are sprays available if you care to reduce this cosmetic problem. Scales of various types may be found on Hackberry. These may be partially controlled with horticultural oil sprays.

Diseases: Several fungi cause leaf spots on Hackberry. The disease is worse during wet weather but chemical controls are seldom needed. Witches broom is caused by a mite and powdery mildew. The main symptom is clusters of twigs scattered throughout the tree crown. Prune out the clusters of twigs when practical. It is most common on Celtis occidentalis. Powdery mildew may coat the leaves with white powder. The leaves may be uniformly coated or only in patches. Mistletoe is an effective colonizer of Hackberry, which can kill a tree over a period of time. It appears as evergreen masses several feet in diameter scattered about the crown.

More on Tree Insects and Disease