[Porsche-O-Phile]

Don’t bother with it until there is NOTHING left on the trees or you’ll end up just frustrating yourself and redoing work a dozen times. Of course this means you’ll have a window of about three hours between when that happens and when it rains for five weeks straight and then immediately freezes, encapsulating the leaves on the ground in an impenetrable layer of ice until spring (that’s what seems to happen here every single year) but at least you won’t have wasted the effort!