While I may not be out in the garden during this time of year, the frozen landscape of Illinois in January still has plenty of life. In fact, there is one animal that toils in the garden all winter, the vole.
Voles are small mouse-like rodents. The easiest way to distinguish them from a mouse is their short, stubby tail. Similar to mice, voles can be found around human habitation, but unlike mice, they are not typically trying to get in our homes.
There are three species of voles found in Illinois: the meadow vole, prairie vole, and woodland vole. The meadow vole is present in the northern half of Illinois, while the other two species can be found throughout. If you had not already guessed, the species' names are indicative of the habitats in which they are found naturally. Additionally, both the meadow and woodland vole are the most likely to be encountered in a home landscape.
While voles are active all year long, it is in the winter when they seem to get into the most mischief. During the warm growing season, food supply is ample, and voles often roam about unnoticed. However, in the winter, as forage becomes scarce, voles will seek out food that may lead to damage to our lawns, perennials, and small woody plants.
A vole's diet is adaptable depending on available food, but they are primarily herbivores (plant eaters). Voles also act as granivores (seed eaters) and, on occasion, will eat insects, snails, or other small animals when vegetation is scarce.
Aided by snow cover in the winter, voles will chew runways across the lawn as they scrounge for food in a home landscape. Melting snow reveals paths of chewed grass from a family of voles.
The destination of these chewed-up runways may be a freshly planted spring bulb collection of tulips, which is a welcome meal to a vole in the winter. As is the bark from newly planted shade and fruit trees. I have seen entire peach orchards ravaged by voles as they chewed the bark off at the base of the trunk.
There are many methods to control voles, but the triedand- true techniques are habitat modification and physical exclusion. Keeping grass mowed short reduces food and cover. Leave a three-inch gap between mulch and the base of trees.
Physical exclusion involves burying hardware cloth six to eight inches into the ground and then up around the plants you want to protect, creating an above- and below-ground barrier. Newly planted and thin-barked trees can be protected with a wire or plastic mesh that is flush with the ground. Mesh openings in any barriers need to be one-quarter inch or less.
Repellents, such as those containing the active ingredient thiram, offer short-term protection. The winter weather may make it difficult to reapply. The voles may be active outside at -20 degrees Fahrenheit, but do you really want to be?
Toxicant baits such as zinc phosphide and anticoagulants are also listed for use in Illinois to poison voles. Place baits in runways or burrow openings. Read and follow the instructions on the product label. These products can impact other wildlife, such as vole predators and ground-feeding birds. Individuals will need to decide if they wish to introduce a toxin that can potentially impact their local food chain.
Trapping is another option. Common snap traps set perpendicular to the vole runway, with the trigger in the runway, will catch a small number of voles. Cover the snap trap to prevent injury to birds or other wildlife. However, because voles can be prolific reproducers, snap traps aren’t effective in large areas. Multi-catch traps can be deployed to capture multiple voles in one day. Place the trap near the burrow opening in the runway. Bait with some birdseed. Check the trap multiple times a day so any trapped voles don’t suffer from exposure.
In my yard, voles weren’t a problem until they started gnawing on my trees. Lawns will regrow, but once a young tree is ringed by a vole, it’s over for that tree. Every fall, regardless of vole activity, I place protective collars around my small trees so that when I finally get back out in the yard next spring, I know my trees will still be there to greet me.
Good Growing Tip of the Week: Because voles are a popular menu item for many predators, you can encourage more opportunities for natural control. Perches for hawks and cover for snakes allow nature to take its course.
