Prepare for Voles - Reducing Winter Damage

Voles can do considerable damage to landscape plants in the late fall and winter. The following is information on voles and how to reduce winter damage in landscapes.

Pine voles live primarily in shallow underground tunnels, but will sometimes forage aboveground. In addition to the damage done during winter, pine voles may cause damage throughout the growing season. Pine voles eat bulbs, tubers, seeds and bark (root bark included), but can damage a wide variety of other plants, including roses, fruit trees, flowers and vegetable garden plants. In many cases the damage from pine voles goes unnoticed until the owner discovers the decline or death of a particular plant. In vegetable gardens, entire plants may be pulled partially or entirely underground. Wilted plants with chewed roots are commonly observed. In flower and bulb gardens, plants may fail to grow in the spring after underground tubers, roots and bulbs have been consumed by pine voles.

Meadow voles prefer wetter soils than pine voles. They live primarily above ground, making shallow surface tunnels or runways. Meadow voles gnaw bark from trunk and branches of trees and shrubs during the winter and early spring. Deep snow cover allows for vole damage to extend higher on trees and shrubs. They also chew out crowns of herbaceous perennials and grasses, and chew out trails in the turf. These trails can be seen in turf or snow cover. Nests are made of interwoven strands of dry grass and contain caches of food. Unless the damage is severe, perennials and grasses will generally recover. As mentioned above under rabbit damage, the survival of woody stems partially girdled depends upon the extent of the damage. Often, deciduous shrubs will send up new shoots later in spring.

Keep grass and ground covers away from trunks of trees and shrubs. Voles require vegetation or other cover in order to survive. By eliminating or reducing this cover one reduces their preferred foods, exposes them to predators and exposes the animals to severe weather. In the home landscape, avoid deep mulching in gardens and plant beds where voles are known to be a problem. Certain mulches are more likely to attract voles than others; avoid using mulches with fine or small particle sizes. Large-sized crushed-stone mulch and pine bark mulch may reduce vole tunneling. Plastic and landscape fabric mulches may increase vole populations and subsequent damage. Frequent mowing of grass around trees and shrubs will help to reduce the potential for vole injury.

Reprinted from the March 19, 2004 edition of Landscape Alert Newsletter from Michigan State University.