Gardeners are disappointed when a portion or all of a plant dies. Injury to the trunk, crown (area at the soil line) or roots generally is the primary cause of death. Death of plants can result from two or more factors interacting to weaken or injure a plant.
Winter injury to fruit plants occurs in the lower trunk, crown or roots near the soil surface.
If damage destroys all inner bark tissue, the plant will die shortly after growth begins in spring. Damaged inner bark will turn brown, while healthy bark will appear greenish yellow.
Severe damage often results in bark splitting or loosening, but this is not always the case. Spring frosts or freezes may cause loss of fruit or leaves, but plants themselves will generally survive if given proper care following the cold period.
Even moderate cold injury to bark, however, makes plants especially susceptible to infestation by borers and diseases such as root and crown rot diseases.
The meadow and pine mouse (vole) feed on plants of all ages. Meadow mice eat the bark and roots both above and below the ground level. Pine mice nest underground, eating bark from the roots near the surface.
Mouse damage is easily noted by carefully removing soil from around the base of the tree and over the larger roots near the soil surface. Bark completely removed around the trunk or roots by gnawing of the rodents will girdle the tree and cause death or severe plant weakening.
Keeping the soil bare and free of grass cover or else mulching around fruit trees or vines will help discourage mice from feeding on fruit plants. Pea gravel (small stones) placed 1-inch below the soil surface and around the tree will discourage mice. When planting trees, allow the soil to settle 1 inch and apply the stone 2 inches deep.
Rabbits feed on bark of trunks and exposed roots of young fruit trees. Rabbit guards, preferably wire screen, wrapped around newly-set fruit plants are suggested to prevent feeding damage.
Where plants are extremely girdled by rodents, death of plants usually occurs shortly after growth begins in spring. As with other types of mechanical injury, weakened plants are most susceptible to drought, cold injury or insect and disease infestations.
For more information on protecting trees and shrubs, contact the Dawson County Extension Office at (706) 265-2442 or stop by our office located at 298 Academy Avenue.
Clark Beusse is the Dawson County extension agent. For more information, call (706) 265-2442.