Late winter is typically the best time to prune trees. Your University of Georgia folks have a nice primer on tree pruning here: http://www.caes.uga.edu/extension/whitfield/anr/documents/PruneShadeTrees.pdf
Steve gave a nice link! Be sure to pay attention to locating the branch-bark collar and position your cut accordingly.
Thanks for the info.
You can take out a dead or diseased branch most anytime if it may harm the tree to wait.