Protecting Trees and Shrubs in Winter

News Article

Winter is a challenging time for trees and shrubs.  Rabbits, wet snow, drying winds, and deicing salts can damage trees and shrubs in the home landscape.  Fortunately, steps can be taken to minimize damage to trees and shrubs in winter.

Rabbits

The most effective way to prevent rabbit damage to trees and shrubs in the home landscape is to place chicken wire or hardware cloth fencing around vulnerable plants.  To adequately protect plants, the fencing material needs to be high enough that rabbits won’t be able to climb or reach over the fence after a heavy snow.  In most cases, a fence that stands 24 to 36 inches tall should be sufficient.  To prevent rabbits from crawling underneath the fencing, pin the fencing to the soil with U-shaped anchor pins.  Small trees can also be protected by placing white corrugated or spiral tree guards around their trunks.  After a heavy snow, check protected plants to make sure rabbits aren’t able to reach or climb over the fencing or tree guards.  If necessary, remove some of the snow to keep rabbits from reaching the trees or shrubs.

Damage may also be reduced by removing brush, junk piles and other places where rabbits live and hide. Trapping and repellents are other management options.

Heavy, Wet Snow

The weight of heavy, wet snow can cause considerable damage to small trees and shrubs. When heavy, wet snow accumulates on small trees and shrubs, gently shake the snow from their branches or carefully brush off the snow with a broom.  When clearing driveways and sidewalks, don’t throw heavy, wet snow onto small trees or shrubs.  Also, avoid dumping snow onto small trees and shrubs when raking snow from rooftops.

To prevent the weight of heavy, wet snow from damaging arborvitae and other multi-stemmed evergreens, wrap the plants with twine or rope in fall.

Desiccation Injury

Narrow and broadleaf evergreens lose considerable amounts of moisture through their needles or leaves during the winter months.  The loss of water is mainly due to strong winds and the bright winter sun.  Once the ground freezes, however, plant roots are no longer able to absorb water. The loss of water from drought stressed plants during the winter months may be sufficient to cause the needles/leaves to turn brown and die.  This type of damage is referred to as desiccation injury or winter burn.  Evergreens most susceptible to desiccation injury include boxwoods, rhododendrons, arborvitae, and yews.  Pines, spruces, and firs are also susceptible to winter desiccation for several years after planting.

To prevent desiccation injury, deeply water susceptible evergreens during dry periods in fall.  Water on a regular basis until the ground freezes in winter.  Moisture loss can be reduced by erecting a shield or screen to deflect drying winds or shade plants in winter.  A simple screen can be constructed with wooden posts and burlap.  Applications of an anti-desiccant to susceptible evergreens may also be helpful.

Deicing Salts

Prudent use of deicing salts by homeowners can minimize damage to landscape plants. Before applying salt, wait until the precipitation has ended and remove as much of the ice and snow as possible.  Use deicing salts at rates sufficient to loosen ice and snow from driveways and sidewalks, then remove the loosened ice and snow with a shovel.  (Deicing salts need to be applied at much higher rates to completely melt ice and snow.)  Mix salt with abrasive materials, such as sand or kitty litter. Avoid piling salt-laden snow and ice around trees and shrubs.

While the amount of salt applied to major roadways cannot be controlled, steps can be taken to minimize damage.  As soon as the ground thaws in early spring, heavily water areas where salt accumulates over winter.  A thorough soaking should help flush the salt from the root zones of plants. If possible, alter the drainage pattern so winter run-off drains away from ornamental plants.

Authors: 

Richard Jauron Extension Program Specialist II

Provide horticultural information to home gardeners and extension staff via the telephone, written communication (Horticulture and Home Pest News, Yard and Garden,  and extension publications), radio, computer (Internet and e-mail), and live presentations.   Also assist with the Master ...