The appearance of dead patches or irregular trails across a lawn often leads homeowners to suspect pest activity. Voles, which are small, mouse-like rodents, are a frequent cause of this kind of damage because they are herbivores with high reproductive rates. Unlike some other common yard pests, voles do not hibernate, meaning they can actively damage turf and plants throughout the year, including under a blanket of snow. Understanding the specific ways voles interact with your lawn is the first step toward effectively managing the problem.
How Voles Interact with Grass and Turf
Voles are herbivores whose diet consists mainly of grasses, seeds, and other plant material. They do not typically consume the entire grass blade above the ground like a grazing animal would, but they do chew the plants down to the crown, which is the growing point at the ground level. The perceived “killing” of the grass is not usually from consuming the blades, but from damaging the lower parts of the stem, roots, and rhizomes.
The visual impact is caused by their preference for creating surface runways, which are narrow, well-worn paths they use to move safely between feeding sites and burrows. As they repeatedly travel these routes, they clip the grass and compact the soil, which prevents new growth and can cause the exposed roots to dry out. This combination of direct feeding on the crown and desiccation along their travel corridors results in the dead-looking trails and patches of turf. Voles also create shallow tunnels and burrows beneath the soil surface, further disrupting the root systems and creating air pockets that inhibit the grass’s ability to thrive in those localized areas.
Recognizing Vole Damage in Lawns
The most identifiable sign of a vole infestation is the presence of above-ground runways. These are shallow, trough-like paths, typically one to two inches wide, that snake through the grass. The runways are often hidden by the surrounding turf and only become fully visible when the grass is cut short or when winter snow melts. Following these trails may lead to small, golf ball-sized burrow entrances near the surface.
Vole damage must be distinguished from the damage caused by moles, which are often confused with voles. Moles are insectivores that create deeper, raised tunnels, resulting in visible ridges or volcano-shaped mounds of soil on the lawn surface. Voles, in contrast, do not create these soil mounds, and their damage is characterized by the distinct, open-air paths of clipped grass and the small entrance holes.
If the damage appears as dead, circular patches or trails of clipped grass, and you can see the exposed soil of the runway, voles are the likely culprit. Vole activity is often most apparent after the snow melts because they remain active throughout the winter, feeding and moving under the protective snow cover.
During this time, they may feed on the bark of young trees and shrubs near the base, a behavior known as girdling, which can be devastating to woody plants. Checking for gnaw marks on the bark of plants near the ground level can provide further confirmation of their presence.
Managing Vole Presence in the Yard
The most effective initial approach to managing voles is through habitat modification, which aims to make the yard less appealing to them. Voles seek dense cover to hide from predators, so regularly mowing the lawn and removing weeds and dense ground cover helps to eliminate their shelter. Bird feeders should be modified or removed to reduce spilled seed, which serves as an easy food source for the voles.
Physical exclusion is an effective method for protecting specific, high-value plants. Young trees and shrubs can be protected by installing a cylinder of wire mesh, or hardware cloth, around the base of the trunk. The mesh should have openings no larger than one-quarter inch and must extend several inches below the soil line to prevent voles from burrowing underneath. The barrier should also extend high enough to remain above the expected snow line in winter.
For direct control, trapping is often the most practical method for localized infestations. Standard mouse snap traps should be placed perpendicular to the vole runways with the trigger end situated directly in the path. Traps may be baited with a small amount of peanut butter and oatmeal, or even a slice of apple. For safety, it is recommended to wear gloves when handling traps or disposing of captured voles, as they can carry diseases.