Tan "seeds" falling by the thousands from my beautiful oak trees

Asked September 29, 2017, 2:43 PM EDT

What is it and what do I do about it?

Rockland County New York

1 Response

The "seeds" are galls. These are irregular plant growths that are stimulated by the reaction between plant hormones and powerful growth regulating chemicals produced by insects such as mites and wasps. Each gall contains an insect that will emerge from the gall in the spring. Both the insects and the galls are harmless to the tree, and the galls should fall from the tree for only a week or two in the autumn. These are not a cause for concern. Here is some additional information about the insects that cause oaks to form galls: https://entomology.ca.uky.edu/ef408