My caltalpa tree (or what I think is a caltalpa) has droped all of its leaves and has skinny long branches sticking in all directions.Every year at this time I take a sharp pair of loppers and prune back these branches as tight to the ball on top of the trunk as possible.This seems to work pretty good .I always liked the look of the branches but was afraid if I didn't cut it back it would grow out of control.My questions are, can I wait till spring to prune it , and secondly can I cut part of the ball on the top of the trunk.Also is there something else I should be doing to protect this tree from disease and pests.

sincerely; marc