Meadow Mouse Control
Don't confuse meadow mice with moles and shrews
Moles have greatly enlarged front feet with prominent digging claws. Shrews have long, pointed snouts and pointed front teeth. Meadow mice have rounded, somewhat blunt, snouts, and their front teeth are chisel-shaped.
Meadow mice are strict vegetarians. Bits of freshly cut vegetation and accumulations of mouse droppings in the runways indicate they are being used.
Meadow mice can be a problem in apple orchards
Meadow mice can become so plentiful that they damage crops and ornamental plants. This is particularly true in the case of apple trees. Tree seedlings are sometimes completely severed, the small stumps appearing as though they had been cut by miniature beavers. Damage of this sort usually occurs at ground level, but under cover of heavy snow, damage may occur well above the ground surface. In orchards, mice are especially damaging, since they live in deeper underground burrows and feed heavily on tree roots.
Cultural. Keep vegetation away from trees for a distance of two feet, through mowing, herbicide application, cultivation, or the use of a layer of crushed stone or gravel 2 to 3 inches deep. Mow orchard sod at 3 to 6 inches height. Scrape dead vegetation away from trees, since it often serves as cover and nesting material for meadow mice.
Mechanical. Wire guards made of 3/8-inch mesh hardware cloth will help prevent meadow mouse damage to small trees and shrubs. Wire cylinders 18 to 24 inches high and about 6 inches in diameter set into the ground around the trunk will keep mice from girdling the stem. These guards also will protect against rabbit damage. Since mice and rabbits travel on snow, wire guards are not reliable when snow depth is greater than the height of the wire.
Trapping. Mouse-size snap traps are effective in reducing the number of mice, and trapping is the safest way to remove mice around homes. Set traps at burrow openings or in runways near ornamental shrubbery, flower beds, gardens, or rock walls. Traps should be lightly sprinkled with rolled oats, and baited with peanut butter or small cubes of fresh apple. Set traps so the trigger lies across the runway, and cover the trap with grass, leaves or an inverted cardboard box of appropriate size. Allow space for the trap to operate freely under the covering. Check traps morning and evening, and reset traps until mice are no longer captured.
Pesticides. For large acreages such as orchards and Christmas tree plantations, the careful use of rodenticides is suggested.
The most selective and effective is hand-baiting mouse runs and holes with treated baits. Since few growers can afford to spend the necessary time to seek runs or holes, treated baits may be distributed by broadcasting selectively into mouse cover. Try to anticipate several days of fair weather when distributing the bait, because rain and snow reduce its effectiveness. Orchards could have both pine mice and meadow mice. Most rodenticides are registered for both species.
Rodenticides are effective in controlling meadow mice in nurseries. Broadcast treated bait to take care of the immediate problem. Bait stations, properly distributed and tended, are a good method of making bait available to mice which move into the nursery after the initial broadcast treatment. You can make bait stations from discarded beverage cans. Enlarge the opening in the end of the can to about 1 1/2 inches in diameter. Dent the side of the can. Place a tablespoon of treated bait in the can, then place the can, dented side down, in the area to be protected.
Placement of the bait container should be marked with a stake or flag so it can be located easily for refilling or removal. Check occasionally to be sure that a supply of fresh bait is present.
This bait is protected from weather and is not readily available to desirable wildlife. Since mice are not attracted to the bait from any distance, it is necessary to place a sufficient number of stations so that all mice find some bait. Use one container for each 80 square feet of nursery bed and place bait stations under grass or other vegetation since mice avoid bare ground.
Mouse repellents are not suggested because of inconsistent results.