Voles are small, stout-bodied rodents often misidentified as common house mice, though they are distinct herbivores known for their short tails and partially hidden ears. As active feeders year-round, these animals inflict significant damage across various types of vegetation, from turfgrass to mature woody plants. Their presence is typically marked by visible signs of their constant search for food and shelter. Understanding the specific forms of this damage is the first step toward confirming a vole issue.
Damage to Lawns and Turf
Voles create extensive networks of shallow, well-worn pathways, known as runways, that crisscross across the surface of lawns. These narrow trails, generally one to two inches wide, are formed as the voles clip and push aside vegetation while traveling and feeding. Runways are often most noticeable in the early spring after the winter snow cover has melted, as the snow provides a protective layer while they remain active beneath it.
These surface routes connect small entry holes that lead down to underground burrows, which typically measure about one to one-and-a-half inches in diameter. Clipping grass stems and feeding on grass crowns and roots causes the overlying turf to weaken and die. This results in irregular patches of dead or yellowed grass, which may feel spongy or soft underfoot due to shallow burrowing activity.
Destruction of Trees and Shrubs
One of the most severe forms of damage caused by voles is the gnawing of bark on young trees and shrubs, particularly during colder months when preferred food sources are scarce. This feeding concentrates at the base of the woody plant, often near the ground line, sometimes extending higher under a protective layer of snow. The damage is characterized by small, irregular gnaw marks left by their incisors, typically 1/16 to 1/8-inch wide.
When this gnawing extends completely around the circumference of the lower trunk, it results in a condition called girdling. Girdling removes the phloem tissue, the layer responsible for transporting sugars produced during photosynthesis from the leaves down to the roots. Complete girdling starves the root system, leading to the decline and death of the tree or shrub above the damaged area. Voles also feed on the surface roots of mature trees, which weakens the plant and makes it vulnerable to other stressors.
Consumption of Garden Plants and Bulbs
Voles are highly destructive to vegetable gardens and ornamental flower beds due to their preference for underground storage organs. They actively seek out and consume the roots, tubers, and bulbs of various plants, often tunneling directly to the food source. Among the most commonly targeted are spring-flowering bulbs like tulips, crocuses, and lilies.
When attacking bulbs, voles hollow them out from the bottom, frequently leaving only the outer shell or a small, neat entry hole at the surface. They also chew irregular holes into root vegetables such as potatoes, carrots, and beets, sometimes pulling entire plants downward into their burrows. The loss of roots and tubers can cause garden plants and young transplants to wilt or fail to emerge in the spring.
How to Identify Vole Damage
Confirming vole activity requires examining the patterns of disturbance and the specific marks left on vegetation. The most distinct sign is the presence of narrow, surface runways, which are pathways pressed into the grass with no accompanying soil mounds. These runways differentiate vole activity from the raised, subsurface tunnels and volcano-shaped soil mounds created by moles.
The size and shape of the burrow entrances are also diagnostic; vole holes are small and neat, usually the diameter of a golf ball or slightly larger, and lack a ring of excavated soil around the entrance. When assessing damage to woody plants, side-by-side grooves left by vole incisors on the bark are irregular in pattern. This contrasts with damage from other herbivores like rabbits, which leave larger, more widely spaced tooth marks and cleanly clip off stems with sharp, angled cuts.