A few years ago, in one of the many horticultural magazines to which I subscribe, I read a column about caring for trees in the fall and winter.
In the past few years, our trees have been subjected to incredible stress: a year of extreme moisture followed by a year of drought followed by another year of more moisture than usual. Although trees are dormant during the winter, exposure to tough conditions can cause more stress. Obviously, therefore, you want to do what you can to minimize that stress.
The International Society of Arborists makes the following recommendations for preparing trees for winter weather:
Rely on mulch. Put composted organic mulch under your tree in the fall or early winter to help retain water and reduce temperature extremes in the soil. A thin layer of mulch will act like a blanket and give the tree’s roots a little extra protection. Do not overmulch. Nothing drives me crazier than seeing a volcano of mulch around a tree trunk, particularly when it is laid up against the trunk. This condition engenders just the right conditions for disease and insect infestation because it keeps moisture on the bark. Give your trees a drink. Winter droughts require watering as much as summer droughts. If temperatures permit, an occasional watering during the winter on young trees can be a lifesaver. But be sure to water when soil and trees are cool but not frozen. We frequently get a thaw during the winter. Hopefully, the thaw will last at least a week, giving the soil a chance to thaw. If the ground is still frozen, water will run right off. This may not be as much of a problem this year since this fall has been relatively wet.
Prevent injuries. Branch breakage or splitting can be caused by ice and snow accumulation or chewing and rubbing by animals. We saw some of this already with our early snow in late October. You may prevent problems with young trees by wrapping their base in a hard, plastic guard or a metal hardware cloth. Wrapping trees with burlap or plastic cloth also can prevent temperature damage. However, it is important to remember to remove the wraps and guards in the spring to prevent damage when the tree begins to grow.
Other damage can be caused when plowing or shoveling snow. Being mindful of trees nearby is crucial. Damage to limbs and trunks from plow blades or a sharp shovel can make trees susceptible to insects and diseases in the spring. One way to avoid such damage is by ensuring that trees are planted away from driveways and sidewalks.
Prune your trees. Fall is a good time to prune trees. Not only are trees dormant in the colder months, but it is also easier to see a tree’s structure when there are no leaves on the branches. Another good time to prune is very early spring before foliation. Proper pruning removes dead or dying branches that are likely to fall on roofs or vehicles in the driveway. Be aware that each tree is different, and pruning at the wrong time or the wrong way can injure a tree. A certified arborist will be knowledgeable and hopefully, also artistic.