I mentioned a walnut next to my drive I wanted to play with. I want to cut everything back to stubs, and see if I can keep it small, though it's already a little taller than I'd like. That'll involve removing all the green. Is it particularly bad doing that this time of year? I believe winter is the time for major pruning, but I'd prefer keeping it from growing more up, and my thoughts are it could help it recover before cold weather comes. Good idea, bad idea, doesn't matter? The tree isn't that important, and in all likelihood, it'll completely come down at some point, but I don't want to ruin my project before it gets going. I'd have to look at it, but going on my unreliable memory, it's 3"dbh, and maybe 12' tall.