Pruning 101

By Mike Lorenc, Conservation Garden Park

Pruning for the first time can be scary. Removing limbs is permanent, and not knowing that you are making the right cuts is anxiety inducing. The guidelines below and a little practice will help you be more confident in pruning your trees and shrubs.

Using the right tool

Pruning tools come in a progression of sizes depending on the size of limb being removed: Simple hand bypass pruners for small branches, long handled loppers for bigger ones, hand saws for those too big for loppers and chain saws for the largest branches. To know which size to use, follow this basic rule of thumb: if removal is difficult, size up. And for the health of the tree and your own personal safety, be sure your tools are clean and sharp.

Remove the three D’s

Start by removing the three D’s: Dead, Diseased, and Dumb. If a limb is Dead, it isn’t helping the tree and could become a problem later, so off it comes. Any branch that is Diseased can be removed as well. To identify diseases in woody plants, look for branches that have black, curling tips or look significantly different from the rest of the tree. Fix branches that cross or rub against each other by removing one of them. Dumb limbs are those growing toward the middle of the tree, toward a home, or any other undesirable direction, and should be pruned off as well.

Making the cut in the right place

Not knowing where to make the cut is the scariest part of the pruning process for most people. Look at where a branch attaches to the trunk or another branch and you will see a wrinkled area where they come together. This is the branch collar. Your goal is to prune off the limb without leaving a stub but without cutting off that branch collar.

When to prune

The best time of year to prune is when the pruners are in your hand. Pruning, even at less-than-ideal times of the year, is better than not pruning at all. But there are better times to prune than others. Generally, early spring, before the plant has leaves, is the best time of year to prune most trees and shrubs. The exception is spring-flowering shrubs like lilac, forsythia, etc. These should be pruned very soon after they finish blooming so they can spend the summer growing flower buds for next spring.

Remove no more than 25%

Avoid removing more than about 25% of the plant’s leaf area in any one year. More than that could stress a tree, as it takes energy to heal wounds and we’ve just removed a portion of the leaf area that creates that energy. If heavier pruning is needed, spread it out over a couple of years.

The wounds created during pruning should be left open to the air. There are many products on the market to treat open wounds on trees, but please don’t use any of these. A tree will seal up its own wound without any help and those products actually keep the wound from healing. Such coverings only promote a moist, dark area which is perfect for bacteria that accelerates decay.

Pruning classes at the Conservation Garden Park are filling up quickly, so grab your spot soon. Alternatively, USU Extension has an extensive selection of pruning videos on You Tube that should answer most of your questions.