Snow can be hard on your landscape trees, especially when it's wet and heavy or comes in with a severe freeze. Proper tree care, both before the weather turns and during the snow storm, improves their chances of surviving unscathed.
The Root of the Matter
Winter can bring mechanical and chemical damage to the trunk and roots of your trees. When clearing snow on walkways and drives near trees and shrubs, avoid mounding the snow up against the trunk. The excess moisture as the snow melts can lead to trunk rot. You also don't want to break or scar the bark and trunk with the snowblower or shovel.
Salt and chemical ice melt can also damage or even kill a tree. If you must use these for safety, avoid placing any removed snow on top the root zone of the trees. Trees that line the road are especially susceptible to chemical damage because of the spray from passing cars. As soon as the weather warms above freezing, rinse the trunks with clear water to remove any salt or ice melt.
A Weighty Problem
For most trees in the yard, the main concern is winter snow weight. Evergreens and softwood trees are most prone to breaking and splitting from the weight of snow.
The best prevention method is defense. Begin removing the snow before it accumulates by gently tapping the branches or brushing upward along the branches with a broom. Don't brush downward or you may end up with a snapped branch. If the snow melts and refreezes onto the tree, you will need to wait until temperatures are above freezing to dislodge the snow with warm water.
Don't Do the Splits
Two things can cause freeze splitting in trunks and branch.
Water seeps into scars or cuts on the wood, and then expands as it freezes.
Warm sunlight heats the sap beneath the bark on the tree so it begins to flow. Freezing night temperatures then cause the sap to expand and split the bark.
Wrapping the trunks of trees in sunny areas with burlap or a winter tree wrap product prevents both types of splitting.
Most snow and ice problems can be avoided with proper pruning. Follow these tips in summer or fall to prepare your trees for winter:
Trim evergreen trees and shrubs so they don't have a flat top that will collect accumulated snow. Pruning to a point or a rounded mound lets the snow slide off.
Remove weak or damaged branches. These branches are the first to suffer freeze damage or break beneath the weight of the snow.
Prune to avoid narrow branch angles. The main branches that extend from the trunk should join the trunk at a near right angle. This results in stronger branches and less snow accumulation – and weight – at the base of the branches.
If your trees do suffer damage, wait until spring to begin damage control unless a broken branch is a safety concern. Many times, the tree will recover. Waiting until growth resumes prevents the removal of healthy, recovering wood.