Oak tree twig galls

Asked April 11, 2018, 1:24 PM EDT

I have a large pin oak that has developed large twig galls caused by wasp larvae. Is there any recommended treatment? I have had 2 different arborists look at this and one tells me that the tree needs to be sprayed and fertilized and the other tells me nourishment is all it needs to keep it healthy. The tree is already well fertilized and I need to know if spraying will help or is it a waste of money.

Jefferson County Kentucky

1 Response

Pin Oaks are notoriously prone to galls. Each gall has a different insect gall maker so spraying is really not practical. The damage is cosmetic, rarely affecting the health of the tree, especially for mature trees.

Unless there are other health issues there is no need to spray or treat the pin oak tree.

UK has an excellent publication in common oak galls:

http://www2.ca.uky.edu/entomology/entfacts/entfactpdf/ef408.pdf


Feel free to contact our office if you have other questions.

Let me know if I can help you further!


Carol Wilder
Horticulture Technician
Jefferson County Cooperative Extension Service
Email: carol.wilder@uky.edu

502-569-2344
200 Juneau Drive
Louisville KY 40243