Prepare Your Landscape for Snow
Snow in the Carolinas is often heavy and wet, causing problems for trees and shrubs such as broken limbs and branches. Additional damage can result from the use of de-icing salts.
While we can’t stop the snow, there are a few things you can do before the storm to minimize its impact on your landscape.
Tie Up Narrow, Upright Evergreens
Narrow, upright evergreens with multiple leaders, such as arborvitae, upright junipers, and ‘Sky Pencil’ holly, are extremely prone to disfigurement and splaying under heavy snow loads. This type of damage can be minimized by tying branches together before it snows.
This can be done by ringing the outside of the shrubs with rope or narrow strips of cloth or by tying the main leaders together high up inside the shrubs. Just remember to remove binding materials after the snow has melted. Here is an illustration of both methods:
Leyland cypress is another evergreen prone to damage during snow and ice. Branches may break or split from the weight of snow or ice or whole trees may topple due to the poor root structure common to this variety. Snow and ice are only one in a long list of problems for Leyland cypress, which includes diseases such as root rot and canker, and insects such as bagworms.
Little can be done to prevent damage to Leyland cypress. The best advice is to remove damaged specimens and replace them with stronger, more resilient species such as ‘Oakleaf’, ‘Nellie Stevens’ or ‘Needlepoint’ holly. Visit this post for more suggestions of screens and hedges for central NC.
Look for Narrow Crotch Angles
The angle at which a branch is attached to a limb or trunk is known as the crotch angle. The narrower the angle, the weaker the attachment and the more likely that branch is to break or split. Some trees naturally form lots of narrow crotch angles, making them extremely susceptible to falling apart in snow and ice. ‘Bradford’ pear is the classic example of this type of weakly structured tree prone to self-destruction in winter storms.
At this point it is too late to correct structural problems in mature trees, but it is a great time to inspect young trees and start training them. Pruning and training ornamental and fruit trees to promote good structure and strong branching will increase their life span and improve survival rates in future storms. Learn more about the correct way to prune and train young ornamental trees from this University of Florida Extension website; Correct practices for training and pruning fruit trees are covered in this NC Extension publication.
Never have a tree topped! This practice, which severely shortens all of the large branches of a tree, is extremely damaging and weakens tree structure. If topping is your only option, the better choice is to have the tree removed and replace it with a stronger species. Learn more about the damaging effects of topping from this Virginia Extension publication.
Use De-icing Salts with Care
De-icing salts can cause serious damage to both the roots and foliage of landscape plants. As snow melts, salt enters the soil, where it damages both soil structure and plant roots. Salts can also be splashed or sprayed onto the leaves of nearby evergreen plants by passing vehicles.
The best way to minimize salt damage in your landscape is to avoid using de-icing chemicals that contain sodium chloride (table salt, sometimes listed as NaCl). Several alternative products are available, if you can find them. Though they are typically more expensive than products containing sodium chloride, products containing potassium chloride (KCl), calcium magnesium acetate (CMA), or calcium chloride (CaCl2) are much less likely to damage plants when properly used.
Coarse sand and sawdust are simple, natural alternatives to de-icing chemicals. While they do not melt snow and ice, sand and sawdust will help provide traction on slick surfaces.
Plants growing within 30 feet of treated surfaces are most likely to be affected by de-icing salt. If your evergreen plants are exposed to sodium chloride laden spray, rinse the leaves with plain water as soon as possible after exposure when temperatures are above freezing.
If salt washes off surfaces and soaks into the soil around salt sensitive trees and shrubs, leach the soil by slowly saturating the area with plain water. This is best accomplished by allowing soaker hoses or drip irrigation to run in the area for two to three hours. Landscape plants sensitive to soil borne salt that are commonly planted in the piedmont include white pine, red maple, boxwoods, river birch, and pin oak.
Learn how to help your landscape recover from snow or ice damage from this Extension Gardener post.
Learn more about minimizing snow damage in your landscape from these great Extension resources:
- Protecting trees and shrubs against winter damage, Minnesota Extension
- Managing winter injury to trees and shrubs, Virginia Extension
- First aid for storm damaged trees, Missouri Extension
For tips on protecting plants from de-icing salts, see:
- Salt damage in landscape plants, Purdue Extension
- Minimizing de-icing salt injury in trees, University of Minnesota Extension
- Trees and shrubs that tolerate saline soils, Virginia Extension
Use Extension Search to find research based information from Cooperative Extension systems across the U.S.
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