Voles
Small rodents that gnaw bark at the base of young trees, eat bulbs and roots, and make runways through grass and mulch.
Also known as: Meadow voles, Field mice
Symptoms and identification
Narrow runways, 3 to 4 cm wide, run through grass, mulch and snow. Bark is gnawed around the base of young trees, often under snow cover in winter, which can girdle and kill them. Bulbs, roots and tubers are eaten, with small round holes at the surface.
Causes
Voles live in dense grass, thick mulch, ground cover and weedy areas, which give cover from predators. Numbers rise and fall from year to year and are highest after mild winters.
Organic treatment
Plant bulbs in wire cages or surround them with gravel, and use snap traps baited with peanut butter and placed in runways, covered for safety. Encourage owls, hawks and cats to hunt.
Prevention
Keep grass short and mulch thin, at least 15 cm away from tree trunks, and clear weeds. Protect young trunks with a cylinder of hardware cloth sunk 5 cm into the soil and standing 30 to 40 cm tall.
Chemical treatment (use with care)
Rodenticides carry risks to pets, children and wildlife. If used at all, follow local law and use only tamper-proof bait stations as the label directs.