Monday, November 19, 2007

Landscape and Turf - Vole Damage

Vole damage can be very extensive in landscapes and often is seen in the fall and winter on woody plants. The following is an article on voles and their control.

Description

The meadow vole, also called meadow or field mouse, is a common problem many landscapes in Delaware. These pests can be very destructive to ornamental plantings, including annual and perennial flowers, turf, shrubs and small trees. Voles are compact animals with stocky bodies, short legs and short tails. Their eyes are small and their ears are partially hidden. The underfur is generally dense and covered with thicker, longer guard hairs. Typically, voles are brown or gray, though many color variations exist.

Voles are active day and night year-round. They construct extensive tunnel systems and surface runways. Several adults and young may live in one tunnel system. Populations seem to peak every 2 to 3 years, depending on food availability, climate and other stress factors.

Damage

Voles damage plant materials by their feeding habits and their tunnel systems, which can ruin turf as well as interfere with irrigation water patterns. Voles will girdle fruit and forest trees causing commercial damage. They also cause damage to ornamental plants. Their teeth marks are very haphazard leaving no particular pattern on the bark or inner portion of the plant material. Voles will feed on trees year-round with most of their damage occurring in fall and winter. In late summer and fall, they will store seeds, tubers, bulbs and rhizomes for winter feeding.

An extensive surface runway system is the most easily identifiable sign of voles. Vegetation near well-traveled runways may be clipped close to the ground. Feces and vegetation may be found in the runways. Pine voles, also native to Delaware, differ from the meadow vole in that they rely exclusively on a system of underground tunnels.

Control

The best way to control voles is to take their cover away. Voles like vegetative covers or litter piles, because they provide food and cover. Elimination of these areas can help reduce populations. Keep weeds or dense brush away from shrubs and tress. Rake and clean up dead vegetation from areas where runways are seen.

Mechanical: Tree guards of hardware, cloth or other suitable material can be used as a barrier around young trees. Since voles are excellent diggers, place the bottom of the guard 6 inches below the soil surface.

Trapping: Use of snap-type mouse traps may be effective in eliminating small populations or reducing their numbers to reduce their damage. Traps should be placed with the bait side in the runway. Baits of peanut butter and oatmeal or apple slices may be effective. Live traps may also be employed.

Poison Baits: Pelleted commercial baits are effective when placed in the runways or burrow openings. Anticoagulant baits are also effective, though multiple feedings are required for control. Repellents are not usually effective. Such baits should be used only by commercial orchards or nurseries. Other than broadcast and hand placements, baits can be placed in various types of waterproof paper tubes. The tubes should be 5 inches long by 1.5 inches in diameter with the bait glued inside the tube.

Adapted from the Delaware Cooperative Extension Factsheet HYG-62 by Dewey M. Caron, Extension Entomologist

4 comments:

Anonymous said...

These guys really are destructive in the hosta beds. As some new hosta varities cost can run into the hundreds of dollars, what's the best way to protect individual plants? I've considered planting in homemade wire baskets and planting in large plastic pots with the bottoms cut out. Any comments?

Gordon Johnson said...

A combined approach using exclusion with wire materials buried around the plants with some extending above the ground; poison bates; and repellents applied routinely would be the best approach for control with hosta beds.

Anonymous said...

I am considering planting new hosta in large nursery plastic pots (2 gallon and larger depending upon mature plant size) and was going to cut out the bottom of the pot completely. Any comments or suggestions.

Gordon Johnson said...

If you are to use this approach, use thick walled pots that it will be hard for voles to chew through and as large of pot as possible so the hostas have enough rooting. The size of the hosta will be directly related to rooting volume.