Some sappy hardwoods can be pruned at this time of year. You can prune Maple, Walnut, Magnolias and Birch. Summertime pruning avoids the typical oozing of sap during the winter and is perfectly safe. Dead or dying branches can be removed at any time.
Early August is a good time to prune Choisya.
Evergreen seldom require pruning but dead or diseased branches can be removed in late summer.
Remember if you are caring for potted trees and large shrubs then a good fertiliser feed will benefit especially in the growing period i.e April – August.