Almost every suburban home in America boasts one or two large landscape trees on their property. These large trees provide us with shade, privacy, and are an anchor for our landscape designs. Therefore, we want to take good care of our trees and maintain them as well as we possibly can. One key to keeping a large tree in good shape is to occasionally trim it back. Trimming a tree requires skill and precision, and if you're unsure about doing the job yourself, it's best to hire a professional arborist to do it for you. However, if you don't trust your tree to anyone but yourself, there are four important methods of tree trimming to familiarize yourself with before you get out your saw.

1. Thinning
Thinning is the most common type of tree trimming, and it's what most people usually have in mind when they hire a professional to trim their trees for them. Thinning is a process of removing excess branches and foliage from a tree so that the wind flows through it more easily, making the tree less susceptible to storm damage. To thin a tree, start by removing any weak branches as well as limbs that cross or rub against each other. Now work your way up the trunk and main branches of the tree, thinning out any excess foliage. Take care not to prune too vigorously as you near the end of each branch. You want the tree to be left with a natural, full appearance at the top and sides.

2. Windowing
Windowing is the process of creating "windows" in the middle of a tree so that you can see through to the opposite side. This is most commonly done when you have a large tree growing close to your home, such that it obstructs the view of the landscape and yard beyond. To window a tree, select one or two horizontal branches in the middle of the tree for removal. Select these branches with care, because a tree that is windowed improperly can easily become disfigured.

3. Skirting Up
Skirting up refers to removing some of the lower branches of a tree to make it easier to walk under or mow under. Ideally, skirting up should be done gradually, as the tree is growing. Every year or two, remove a branch that is lower to the ground than you'd like, cutting it flush with the trunk and then allowing it to heal over properly. If you are skirting up an older tree and some of the branches to be removed are quite large, you may want to consult with an arborist or your local nursery or garden center. You may need to paint the wound over for a year or two to help it heal and prevent disease from entering the tree.

4. Crown Reduction
Crown reduction is the process of making a tall tree shorter by trimming the tallest branches at its top. If you are dealing with a very large landscape tree, such as an oak or maple, it's wise to hire a professional firm to do the work for you, because they have the right equipment to prevent accidental injury.

Remember, anytime you are trimming a tree, always select your branches very carefully and consider them twice before you actually cut. Once a branch has been cut, there's no way to put it back, and many a fine landscape tree has been disfigured by a poor trimming job. If you do hire an arborist for a professional tree trimming, be sure to get some references so you can look at trees they've previously trimmed before hiring them. With an occasionally trimming every five years or so, your trees will grow beautifully and stay well maintained in your yard for years to come.