Ask Mr. Smarty Plants

Mr. Smarty Plants is not sure which earlier question you are referring to, but I suspect it may be this one that discussed pruning oak trees in central Texas. There are some important differences between Texas and Wisconsin besides the way we talk.

February in Central Texas is often more like spring than like winter. In fact, as I write this, on February 17, it is 74 degrees here in Austin. So, the insects that spread oak wilt get active earlier around here than where you live.

Here is a link to a USDA Forest Service site that discusses prevention of oak wilt in Wisconsin. This is a portion of their advice:

Do not prune or wound oaks during their entire growing season. The growing season begins when the buds swell in early spring and ends in fall when frosts and freeze-up occurs. The beginning and end dates of the growing season vary each year, depending on weather conditions in different areas of the state. Please be aware that avoiding pruning and wounding of oak trees during the entire growing season is a more cautious approach than is recommended in most publications. If an oak tree must be pruned or is wounded during the growing season, immediately cover the wound with a tree wound paint.

Mr. Smarty Plants would add to this that, whenever you cut a limb that is bigger than your thumb, you should always paint the wound and you should always disinfect your tools prior to cutting with a 10% bleach solution. Do this before you begin and again between each tree.