Pruning cuts to help your trees look better and live longer

Pruning is both an art and a science. In order to prune properly, you should understand the types of pruning cuts and the difference between good cuts and bad cuts. There are two basic cuts — thinning cuts and reduction, or drop-crotch cuts.

Thinning cuts

Thinning cuts are when you cut a lateral branch off, down to a larger branch. It’s almost that simple. Thinning cuts are usually done to reduce competition of branches that are too close together, or to remove a branch that is crossing and rubbing a more desirable branch. They are also done to remove branches with a bad crotch angle. A bad crotch angle is usually less than 45 degrees and often the bark of the two branches grow down and pinch together (including bark) rather than form a little ridge (branch bark ridge).

It’s important that the cut is close to, but not flush with the larger branch. Some trees are a little better at telling you where to make the cut than others. The branch bark ridge and the branch collar need to be identified. The branch collar is where the wood from the larger branch grows together with and around the lateral branch wood and it is usually a little more swollen at the base of the lateral branch. Your cut should be next to the branch collar without damaging it.

Also, avoid leaving a stub sticking out beyond the branch collar as the stub will die and the wound will stay open longer.

Reduction or Drop-crotch cuts

Drop-crotch cuts are when you cut a larger branch off, down to a lateral branch. The purpose of a drop-crotch cut is to encourage a tree to grow in a specific direction. The lateral branch should be at least 1/3 the size of the branch that is being cut. Otherwise, you will encourage a lot of small branches (water sprouts) to develop at the cut. This results in what is often called a “witch’s broom”. If you do have water sprouts develop at a large drop-crotch cut, remove them over a couple of years. Their presence may help a large wound close.

If you are continually drop-crotching a tree to keep it small, you have the wrong tree in that location. It can be done, but you will continually fight the genetics of the tree.

The drop-crotch cut should be just above the branch bark ridge, with the heel of the cut about 30 degrees lower.

One practice that should be avoided is stubbing branches. Not only is it unsightly, it will shorten the life of the tree and cause other structural weaknesses.

If you get out and prune your own trees, be targeted in your practice and your tree will look better and live longer.