Trees are one of our greatest natural resources and we are fortunate to live in a city that is graced with an abundance of them. Our city fathers (and mothers) and park system caretakers had the wisdom to understand the valuable contribution that trees make to our environment, and the foresight and vision to ensure that their majestic beauty graced miles of parkways and boulevards.
Trees not only add to the beauty of our urban landscape, they make other contributions to the environment. Trees (and other plants) scrub our air through the process of photosynthesis; removing carbon dioxide and releasing oxygen. Every acre of growing evergreens produces enough oxygen each year for 18 people. In addition, trees on our boulevards and yards provide shade and help keep our homes cool in the hot summers. And, of course, trees provide us with wood, nuts and fruits.
We often take the trees in our urban landscape for granted, and when one “goes missing” on the boulevard or we are forced to remove one in our own yard, we feel the loss. The devastation of Dutch Elm disease and Emerald Ash Borer has made us acutely aware of the need to take care of the trees that were spared, and the new ones that were planted to take place of those that were lost. One of the easiest things we can do to ensure the health of our urban forest is to make sure our trees get enough water; not only the new young trees, but also the very old and gigantic specimens that still grace our boulevards and yards. This is especially important during periods of drought. While we tend to worry about watering our lawns and gardens, we often don’t think about watering the trees.
Another important part of maintenance of trees and woody landscape plants is something that most of us do not even think about. Regular pruning is important to the health of your trees. The Minneapolis Parks Forestry Division prunes boulevard and park trees regularly to remove dead/dying branches or branches that are rubbing against each other. We should do the same with our own trees. You may see Minneapolis Forestry pruning trees in the next two months and that is because the best time to prune trees and shrubs is when they are dormant and that is now.
Pruning is important to the health of your trees and shrubs – especially when you remove branches that are dead or dying as a result of disease, severe insect infestation, damage from animals or storms, or branches that are rubbing against each other. Pruning will also encourage new growth, and flower and fruit production. Another reason to prune is to improve the appearance, and maintain the size or shape and/or the original purpose of your woody plants. You may want to remove unwanted branches or suckers, to control the size of your plant and/or maintain its nice, natural shape. You may also want to prune trees or shrubs that obscure the entry to your home, cover your windows, and you may be required to trim ones that obstruct the vision of drivers or pedestrians.
The truth is that all of our trees or shrubs will benefit from regular pruning beginning with first year they are planted. Trees are an important investment in your landscape and you should protect this investment. Unless your tree is small and you know what you are doing, it is best to hire a certified arborist. When a tree or shrub is pruned properly you should not be able to tell that it has been pruned. The best practice of pruning is thinning. That is the selective removal of branches — completely removing them back to the stem or another branch. Thinning maintains the natural shape of your plant and as stated earlier, if your plant is pruned properly you should not be able to tell that it has been pruned. (No reputable tree trimmer should suggest, “topping your tree” — topping is extremely harmful to trees and is not an accepted professional practice.)
If your tree is small enough and you wish to prune it yourself here are a few guidelines for you to follow:
• Remove diseased, broken or dead branches.
• Remove any downward-growing branches.
• If two limbs are crossed, entangled or otherwise competing, remove one of them completely at its base.
• Remove any limbs along the trunk that are bigger in diameter than the trunk.
• Remove suckers coming up from the roots or low on the trunk.
• Remove vigorous vertical branches, called watersprouts.
• Make pruning cuts close to the branch collar at the base of the limb. For larger limbs, start the cut from the underside of the limb to avoid tearing the bark.
• Remove large limbs first, starting with the top of the tree.
• “Thinning” cuts remove entire branches at the branch collar and are usually the recommended type of cut.
If you are interested in learning how to prune small/fruit trees, you can participate in a hands-on learning experience conducted by a U of MN Extension Educator at Loring School’s garden orchard on Saturday, March 8, 1:30-3:30 p.m. More info is available elsewhere in this issue of the Camden Community News.