The meadow vole (Microtus pennsylvanicus) is one of the most abundant small mammals in North America and a major pest species across Montana's lawns, pastures, orchards, and gardens. Small, compact, and mouse-like in appearance — but shorter-tailed, with smaller ears and eyes — meadow voles live in dense grass and ground cover, creating networks of surface runways and shallow underground tunnels that are often invisible until snow melts in spring.
Meadow voles are prolific breeders. A single female can produce 5–10 litters per year with 3–6 young per litter. In peak population years — which occur cyclically every 3–5 years — vole numbers can reach staggering densities. It is during these population peaks, and particularly over the winter months when voles are active beneath snow cover and protected from most predators, that the most dramatic damage occurs.
Spring snowmelt in Montana frequently reveals extensive networks of surface runways, bark-stripped ornamental trees and shrubs, and dead patches of lawn — damage done invisibly over the winter months. For orchardists, a single high-vole winter can kill young trees entirely through complete girdling of the root crown.
Size
5–7 inches including tail; ¾–2 oz
Color
Brown to gray-brown; lighter undersides
Active Season
Year-round (active under snow in winter)
Risk Level
Medium–High (lawn, orchard, and garden damage; severe in peak population years)
Habitat
Dense grass, ground cover, mulched beds, snow cover
Reproduction
Up to 10 litters/year; populations cycle every 3–5 years
SIGNS OF INFESTATION
Signs of Meadow Vole Activity
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Surface runways — Narrow, clearly defined paths (1–2 inches wide) through grass, connecting burrow entrances; most visible when grass is low or in early spring after snow melts.
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Gnawed grass and plant stems — Short-clipped grass stems and pieces of cut vegetation scattered along runways.
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Girdled tree or shrub bases — Bark stripped from the base of young trees and woody shrubs, often in a band at ground or snow level. Complete girdling kills the plant.
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Burrow entrances in turf — Small holes (¾–1 inch diameter) in lawns and meadow areas, often concealed by grass.
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Winter damage revealed in spring — Extensive dead lawn patches, runway patterns, and girdled plants visible after snowmelt.
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Small dark droppings — Vole droppings (approximately ⅛ inch) scattered along runways and near food sources.
HEALTH RISKS
Meadow voles can carry hantavirus, leptospirosis, and tularemia, and their burrows and runways harbor fleas and ticks. Direct human contact with live voles is uncommon, but handling dead animals or cleaning areas with heavy droppings concentrations should be done with gloves and respiratory protection. Hantavirus can be transmitted through inhalation of dust from dried droppings.
PROPERTY DAMAGE
Vole lawn damage — the network of dead runways and brown patches revealed each spring — can require extensive overseeding and turf repair to restore. Girdling of young trees and ornamental shrubs kills plants outright if the bark is removed in a complete ring around the trunk. In orchards, this represents a serious financial loss. Damage to garden bulbs, root crops, and perennial root systems from burrowing voles can also be significant, particularly during high-population years.
