Young trees are like children; proper training from a young age prevents minor flaws from becoming major problems later. Structural problems on trees are difficult and expensive to fix once the tree grows large, but just a few cuts on a young tree can set things right. Correct pruning cuts reduce future work and expense.
Winter is the best time to prune trees. In winter it’s easy to spot where the problems are, and winter pruning is not harmful to trees because they are dormant. The worst tree defects can be fixed, without climbing, when your trees are still young. There are some simple and easy steps you can take to train young trees.
First, here’s how to make a proper cut without hurting the tree: To cut tree limbs properly make three cuts: 1. Make a cut on the underside of the limb a few inches above the spot where it meets the trunk. This will prevent tearing or peeling of the bark when you cut the limb off. 2. Cut downward from above, a few inches further out on the limb, until it falls. This will leave a short stub. 3. Cut the stub off. Make the cut straight across the remaining limb, not parallel to the trunk. The exposed end should be round, not oval. Take special care not to damage the “branching collar”; the wrinkled flare of bark around the base of the limb. This will then grow and quickly cover the open cut. Never leave a stub longer than a half-inch, because the bark can’t heal over your cut and this invites tree problems.
The reason for cutting in three steps is that you can’t cut at the proper angle from above, because the tree trunk interferes with your saw. The final cut has to be made from below. The heavy branch will cause your saw to bind in the cut and get stuck. By cutting most of the limb off first, you take the weight off so you can make the final cut easily and precisely.
The most important defect to fix early is too many trunks. This defect is called “co-dominant leaders.” You should cut off all but the strongest, straightest one, right at the base of the tree.
Another common defect to look for is called a “bark-included crotch.” This defect occurs when, instead of a healthy limb attached to the trunk, a tree forms a close crotch with a layer of bark hidden inside. The limb and trunk are not well attached, since the bark forms a seam down inside the tree. The best and easiest time to fix bark-included crotches is when they first occur on young trees, before the limb is thicker than your thumb. You can simply cut the offending limb off at the crotch and it will heal over in a single season.
As young trees grow you should gradually “limb up” the lower branches before they grow too thick, so there is clearance to mow or walk underneath. Proper pruning cuts will heal quickly and disappear. Just make sure not to injure the “branching collar” when you cut.
Many people are afraid to prune or cut trees for fear of damaging or killing them. This fear prevents them from making simple corrections when they’re easy to make. Remember “a stitch in time saves nine?” Get over your fear and you’ll actually have healthier, stronger trees. You’ll be amazed how proper pruning cuts heal over without a trace. Once you see this work you’ll be proud of yourself.
Steve Boehme is a landscape designer/installer specializing in landscape “makeovers”. “Let’s Grow” is published weekly; column archives are online at www.goodseedfarm.com. For more information call GoodSeed Farm Landscapes at (937) 587-7021.