Snow damage on juniper. Photo credit Sandy Feather.
Heavy snow and ice storms can cause major damage to trees and shrubs. Who hasn’t heard the sound of tree branches cracking and breaking under the weight of ice?
Homeowners often ask whether their plants are better served by knocking off ice and snow or by leaving it alone until it melts. Most Extension horticulturists recommend leaving ice-covered branches alone since knocking the ice off often causes even more branch breakage. Snow itself is not dangerous to plants. In fact, it acts like a natural insulator helping to protect plants from freezing and thawing temperatures. As such, there is no need to try to remove it from plants. However, if the snow is heavy and is severely bending branches, it can be gently removed by brushing upward with a broom or lightly pushing limbs upward with a pole. Beware of standing underneath taller shrubs or even small trees when you do this. Do not shake the shrub or tree as this can cause more injury to the plant (and to you for that matter!)
When shoveling or snow plowing near shrubs, avoid piling excessive amounts of wet, heavy snow on them since the weight of compacted snow can break branches. If foundation shrubs are situated underneath areas where snow or ice often slides off the roof, they can be protected with A-shaped wooden frames. Upright shrubs such as arborvitae and some junipers that may splay outward and lose their shape under the weight of snow can be supported by tying strips of cloth or twine around the shrub or by tying the leaders together inside the shrub to maintain their shape.
If branches break during a storm, seek professional help to prune the limbs of large trees. In fact, Penn State Extension urban forester Brian Wolyniak suggests that winter is a good time to inspect trees for dead branches, crossed branches, or branches that overhang areas where falling limbs may cause a problem. If these are higher than can be reached from the ground, a professional should be called in to perform preventative pruning.
On smaller trees, broken branches should be pruned back to the main branch or trunk. Damaged evergreen shrubs, like rhododendron and cherry laurel, and deciduous shrubs can be pruned back severely in the spring and will rejuvenate.