It is believed that the Oak Wilt disease started in Wisconsin. The best time to prune Oak Trees is in the dead of the winter. In Wisconsin the deadline is April 1st OR before the sap begins to run. This video is a good watch if you are interested. Oak Trees are an asset to any property owner. We are here to help. If you know your Oak tree needs attention our estimates are free. Time is running out so Book now Janesville, Milton, Edgerton, and Dane County Neighbors.