We’re in the middle of winter here in Atlanta and it’s the time of year when most people do NOT think about tree trimming. But that can be a mistake — this can be the BEST time of year for certain types of trimming. Here’s why. Most trimming of healthy trees can be done anytime. Go ahead and do minor pruning and shaping 12 months a year. Here’s the exceptions: Heavy trimming, such as trimming affecting more than 10% of the crown volume, or trimming big branches (like cuts on branches and trunks exceeding 6 inch diameters, is best performed in the winter when trees and insects are dormant. It just puts less stress on the tree. And flowering trees are another exception. Most flowering trees and shrubs are best trimmed after the flower petals fall off in the Spring. And it’s best to avoid all but the most minimal trimming when trees are already stressed, such as in the heat of summer.
Mistletoe clumps in oak tree in Atlanta area.
See the clumps of mistletoe in the crown of the oak tree in the photo above? A little sprig of mistletoe can liven up your Christmas celebration, but a lot of it can be harmful to your trees. Mistletoe is a destructive parasite. If you snap off some, you’ll see how well attached it is to the tree branch. And it sucks the life out of your tree. In wet weather, trees can tolerate a small amount of mistletoe. In times of drought, a large mistletoe infestation (such as in the photo above) can be deadly. So whenever you trim your tree, try to remove mistletoe nearby. The proper procedure is to trim off the wood it’s attached to back to healthy tissue, or the entire branch if necessary. If the branch is large, it’s acceptable to just snap off the mistletoe clump, but you’ll be doing it again soon.
Arborists are always debating the proper time of year to trim various trees. In the winter, its easy to spot defects like crossover branches and cankers (and mistletoe!) But without the leaves, it can be hard to spot dead branches. But with the leaves on, it’s nearly impossible to spot the mistletoe. It’s best to have a regular visit by an arborist you trust, who becomes familiar with your trees and who has seen them over several years.