Trees can be pruned to remove dead or diseased branches, to improve the shape, to let in more light, to remove lower branches that block the view, or to reduce risk. But otherwise, removing foliage can stress trees. If pruning is necessary, it’s best to prune in late winter, before spring growth starts. However, for trees such as flowering plum or magnolia that bloom early in the spring, wait until after they finish blooming if you want to enjoy the flowers.
Prune just outside the branch collar, but don’t cut into the collar itself. Let the tree heal itself rather than putting any paint or dressing on the cut.
For West Lafayette’s Tree Manual and Guide to the West Lafayette Landscape Ordinance, see http://www.westlafayette.in.gov/egov/docs/1321371969_676940.pdf