Oak tree damage

Asked June 11, 2020, 12:27 PM EDT

Something is eating (ravishing) the leaves on my oak trees. We live on 20 wooded acres and so do my neighbors on both sides. Our oak trees are quickly losing all leaves on branches. What is this insect? What can I do to help stop it? Will it kill my trees? Any help would be greatly appreciated. Thank you, Rhonda Guido

Washtenaw County Michigan

1 Response

Oaks get fed on in spring to early summer most commonly by gypsy moths. This insect pops up every so often when we have dry springs. There is a fungus that normally keeps it in check when we have good rainfall. Their feeding can vary from lots of holes in the leaves to trees being stripped of their foliage. If the feeding goes beyond 50 to 70 % of the leaves the trees will begin to put on new leaves by mid summer. Lack of rainfall can slow the development of new leaves. Gypsy moth during the 80s stripped forests across the state but this changed in the late 90s when a fungus was introduced across the state. In Washtenaw it varies from year to year based on rainfall. The rains in the last week will help to spread the disease but it gradually slows down the insect. Oaks do not die from insect defoliation which occurs even from native insects. It does put them under stress and if they were not healthy to begin with it can injure them. The history in this county in the last 20 years is that a population will increase during dry periods and disappear in years with adequate rainfall. In 2007 Hudson Mills metro park trees in one section of the park were totally stripped and by the next season with good rainfall in 2008 the population died off. In 2018 Ann Arbor had serious levels of Gypsy Moth and the following spring they were hard to find. See the following information: https://www.canr.msu.edu/news/growing_populations_of_gypsy_moth_caterpillars_raise_concern_for_landscapes