The population of voles or meadow voles (Microtus spp.), extremely common small brown short-tailed, small-eared mice found in every home garden, is at its maximum by the end of fall. After all, with females reaching sexual maturity by the age of 25 days and producing 3 to 6 litters per year, each litter with an average of 4 to 6 babies, that makes for a lot of hungry voles by the time the first snows fall: up to 2,000 per hectare by November in a really bad year. Of course, the vast majority of them die over the winter, but they often cause severe damage to your garden plants before they go.
Damage is rarely observed during the summer, as voles are usually content to discreetly nibble on green leaves and given the millions that fill your lawn and gardens, that scarcely counts. As fall advances and there is less and less fresh foliage, they switch to seeds and fallen fruit, still attracting little attention. It’s in the winter, though, when hunger drives them to nibble on the bark of shrubs and young trees, especially fruit trees, as well as the crown and roots of your perennials, plus the bulbs you so carefully planted only a few weeks earlier, that voles can be so devastating. Worse yet, the damage is often done sight unseen, as they tunnel under the snow.
Protecting Trees and Shrubs from Voles
Traditionally, gardeners have used wrapping or other techniques to protect trees and shrubs from vole damage during the winter. There’s more information about that here: Protection Against Voles. However, another option is to be proactive and reduce the vole population before winter even arrives.
Trap the Varmints
To do so, set out four or five mouse traps in your garden in late fall. Any mouse trap will do, whether it’s a traditional spring-loaded mouse trap (the one seen in cartoons, fixed to a thin piece of wood) or one of the more modern mouth-type plastic traps.
Don’t bother with live traps. Not only are they expensive, but being trapped usually results in the animal dying from shock a few days after it’s released anyway. Besides, releasing live voles anywhere is illegal in most areas, plus it’s just plain unneighborly. I mean, would you accept having a load of live mice dumped in your yard?
Bait the traps with a paste of oatmeal mixed with peanut butter or spread peanut butter onto a piece of apple. Now place them near the plants you want to protect. Even better, if you can make out a vole path (unfortunately, they’re none too visible in the fall; they’re usually not noticed until spring, when it’s too late) and place your traps near one, you’ll catch even more.
Each morning (voles are mostly active at night), check your traps to remove the dead voles and refresh the bait. When you no longer catch any, try a new spot. The number of voles you catch when the population is high can be astounding. It’s not uncommon to catch dozens in just a small urban yard, hundreds on a half-acre lot.
There you go: act now to reduce the vole population and you may not need to offer your plants any special protection during the winter.