In the later fall and winter, when other food sources are scarce, voles, mice and rabbits eat the bark and underlying tissue of young trees. Voles frequently girdle a tree by removing a continuous strip of bark and cambium around the circumference of the tree, usually within 30 cm of the base of the tree. Trees do not recover from this girdling and usually die during the following year.
Some commercially available repellents used by fruit growers can effectively discourage voles, rabbits and deer from feeding on trees. SKOOT and other brand name repellents contain Thiram, a distasteful but harmless fungicide that discourages animals from taking a second bite. With a paint-like consistency, the repellent can be painted onto the tree’s bark from below the original soil line to a height of 150-175 cm to discourage deer browsing, and feeding by rabbits and voles.
Before applying the fungicide, the bark mulch and a few centimetres of soil is removed from the base of the tree to allow the property manager to paint the trunk of the tree from below soil level to a height of 150-175 cm with the repellent to discourage feeding by voles, rabbits and deer.
Ensure complete coverage when applying the repellent and follow the package directions.
Where there is a known threat of vole and rabbit damage, a galvanized hardware cloth cylinder with a 6-8 mm square mesh can be set in place around the base of the tree and buried to a depth of 5 cm into the soil.
The soil and mulch is then returned to its original form and depth, covering a few cm of the painted trunk at the base of the tree before three 15-20 cm wire staples are used to fix the cylinder in place, centrally around the trunk of the tree. Short pieces of poly-coated wire secure the cylinder to a 125 cm stake, driven at least 25 cm into the soil.
Individual Tree Wraps and Tree Guards may be more effective where vole and rabbit damage is concerned, in areas where there is a low deer population and minimal risk deer browsing.
Rabbits and voles gnaw the bark of young trees, consuming the outer and inner bark, exposing the inner wood. If the chewing extends more than half way around the trunk, the tree may not survive.
Protect the tree by wrapping a soft, flexible plastic tree wrap around the trunk. Starting at the bottom, bury at least 5 cm of the wrap below soil line and work your way upward. Be sure to wrap beyond the typical snow line. Remove the wrap in the spring.
In areas where deer may be a problem from browsing or rubbing their antlers against the tree trunk, use a tree guard 100-125 cm in length.
Tree guards also offer some protection from winter sunscald.
Many different tree wraps and protectors are available from garden centers and farm supply outlets. A flexible plastic tree wrap is shown above on the left. A ventilated, corrugated tree guard is shown on its right. We used both of these tree protectors to protect the Native Maples that were planted recently. Both installations include the use of a hardware cloth cylinder supported by a sturdy stake.
More information available at:
Protecting Trees from Animal Damage: http://www.agr.gc.ca/eng/science-and-innovation/agricultural-practices/agroforestry/diseases-and-pests/protecting-trees-from-animal-damage/?id=1198877618448