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If you have oak trees, perhaps you noticed something unusual growing on the branches in recent weeks.

Those brown or green-colored balls on the trees are known as oak galls. Insects are the culprit and for this particular issue, the offender is a stingless wasp. The wasps inject a hormone into the plant’s tissue that produces abnormal, round growths around their developing wasp larvae.

Overall, galls don’t create any long-lasting harm, but if oak trees are heavily infested by these wasps, it could damage the tree. The recommended control method is to prune out a severe outbreak of oak gall. Contact our team of experts at