Unpopular opinion: you should not prune oaks in spring, but a customer in Madison yelled at me for waiting until July
I used to prune oaks whenever the saw was sharp, then a county forester pulled me aside after a job in Dane County and said the sap beetles that carry oak wilt are most active April through June, so I've pushed everything to late July or winter since. Now half my clients think I'm dodging them in spring, and one guy hired someone else who cut his oak in May. Do you folks hold the line on summer/winter pruning or just go when the customer pushes back?