Voles

• Voles are small, sturdy rodents the size of a mouse with roundish ears partly hidden in their fur. These rodents, 3 to 6 inches long, are voracious eaters. They forage on plant bulbs, roots and bark. They thrive on woody shrubs like azaleas and girdle the trunks near ground level. Their extensive tunnels may encircle a shrub, severing roots and creating air pockets that dry out the roots. Because voles dig extensive subterranean tunnels, they may be undetected until azaleas are damaged. While voles do not directly kill the azaleas, they weaken the shrubs, making them vulnerable to disease and insect infestation.
  
  

Azaleas

• Azaleas attacked by voles appear stunted or weak. Symptoms may include spindly branches and yellow leaves. Pull back mulch or leaves to inspect the azalea trunk. Small grooves girdling the shrub indicate voles. Voles eat roots, chew bark and climb on low branches to chew tender woody shrubs and devour leaves. Poke a screwdriver into the soil and prod for a telltale tunnel leading to the azalea. The tunnel may be covered with grass or mulch and lead to a network of burrows around the azaleas.
  
  

Habitat

• Voles hide in grass.David De Lossy/Valueline/Getty Images
  
  Habitat management often eliminates vole problems. Pull mulch away from azalea trunks. The mulch provides cover for voles to feed on the shrubs. If the azaleas are in the midst of lawns or turf grass, mow the grass regularly. Voles use the turf for tunnels. Remove weeds and vegetation around the azaleas that conceal the pests. If practical, create a barren soil strip around the azaleas, as voles prefer cover when feeding. Voles tunnel easily in loose soil. Tamp down tunnels and fill any soil pockets around landscape plants. Hardware cloth or screen around the trunk may protect some azaleas, but does not protect roots.
  
  

Control

• Encouraging predators helps control voles. Cats, terriers and hawks are typical vole hunters. These predators help discourage but rarely eliminate voles. Voles repopulate quickly, maturing at five weeks and producing five to 10 litters per year. Vole repellents and burrow fumigants are rarely effective. In heavy vole infestations, baits or rodenticides are the most practical control. Follow all label precautions to protect children, pets and wildlife from the baits. Voles carry infectious diseases and parasites. Wear rubber gloves or use a plastic bag as a glove to pick up dead voles. Do not feed dead voles to pets.