Oak tatters has struck some oak trees in Iowa, Illinois and several other states.
Oak tatters makes leaves appear lacy or “tattered,” hence the name. The condition primarily affects white oaks, bur oaks and swamp white oaks. Red oaks are only occasionally affected according to the Iowa Department of Natural Resources.
Oak tatters appears to be caused by damage to leaf buds and could be from low temperatures before or during leaf expansion. Herbicides may also affect the development of oak tree leaves; and insects feeding on the leaf buds or developing leaves may also contribute to tatters.
Healthy trees can survive the stress of producing replacement leaves, but repeated damage combined with other stressful conditions like drought or other diseases could make the tree more susceptible to other problems.
The DNR recommends adding mulch to an affected tree, watering during extended dry periods and trying to minimize other stresses like changes to the site near or around the tree.
“Trees should recover unless they are tattered for three or more years in a row,” said Tivon Feeley, forest health program leader for the Iowa Department of Natural Resources.
In addition to Iowa and Illinois, tatters have been seen this year in Minnesota, Michigan, Wisconsin, Indiana, Ohio and Missouri.