Keeping your property tidy sometimes requires you to trim some trees. The book "Gardening For Dummies " gives this advice: "pruning is part maintenance, part preventative medicine and part landscaping." We trim trees to encourage flower or fruit development; to keep them a manageable size; to prevent them from damaging buildings, other property and people; to create hedges, or simply to improve the tree's looks. Tree trimming can be hazardous work, so if you have any large trees that need a major "haircut," consider hiring an arborist or tree trimming service.
Pruning Trees Yourself
Cut off branches that no longer appear alive, but don't forget that some trees are deciduous---they lose their leaves in the colder months and can look dead. You should trim many trees, such as fruit trees, in winter, so determining which branches are dead and which are still alive might be difficult. If you notice dead branches in summer, prune them at any time.
Trim branches that touch each other or that grow across other branches. When you cut, leave the branch collar, or bulbous area where the branch meets the tree's main trunk. Cut close to the collar and do not leave a stub of the branch.
Trim flowering trees after they finish blooming because you won't want to spoil the beauty and enjoyment the flowers will bring or prevent the fruit or nuts that the blossoms produce.
Saw larger branches in two separate cuts: one halfway through the branch from the bottom side and the second to meet the first cut from the top side. This practice will cause the branch to fall off cleanly and not tear or otherwise damage the trunk.
Grind up the branches you have cut with a chipper-shredder---many trees produce bark and compost that are good for other plants when spread as mulch. Check with your Agricultural Extension Service to learn which trees can be used for mulch. For example, black walnut leaves are undesirable as mulch because they have ingredients that do not allow other plants to grow where they lie.
Become familiar with your various trees' needs and preferences because different types of trees have different trimming needs. Many books are available on the subject.
Avoid topping trees. Many sources report that doing this can be detrimental to your tree's health.
Trim trees that might block the vision of motorists driving by your property. Also trim branches that hide your home's entry doors---burglars prefer hidden access areas, so keep these areas open.
Check with your local nursery, Master Gardener program or Agricultural Extension Service to learn when to prune trees that grow in your area. For example, don't prune oaks from spring through fall because the cuts can leave them open to a wilt disease.