You might have several different types of mice nibbling on your Heirloom / Open Pollinated Vegetable Garden plants. Field mice are chunky in build, with small ears that are almost concealed in fur. They are white underneath and gray-brown on top. House mice, which is less likely to damage your vegetable garden plants, is gray all over, with large, distinct ears. Deer mice range over most of the continent, having whitish underpart’s as well as whitish legs and feet, are grey on there sides and top and tails over 2 inches long.
Mice have been known to move into mole tunnels and use them to get at the roots of your vegetable plants. They create trails on the surface through long grass, weeds, and brush, and can also burrow underground. They are most damaging in winter, when they chew the bark of young fruit trees, sometimes girdling and killing the trees. They are generally active all year round. Roots of vegetable and flower plants in the Heirloom / Open Pollinated Vegetable Garden are a favorite for mice. These rodents also gnaw on roots of young trees and shrubs, as well as on bark buried under the snow during the winter months.
We think the traditional mousetrap still works the best. We have tried sticky pads but have never caught a mouse on them. Mouse bait works but it seems the mice like to hoard the stuff, and when it does kill them they can really stink. Bait the traps with a tiny dab of peanut butter, or a 50=50 mix of peanut butter and uncooked oatmeal. We have found that to eradicate mice effectively we had to declare all out war on them and put out a whole bunch of traps all at once. A steel drum with bait inside makes a very simple homemade mousetrap. The mice scramble into the standing drum, and once they are inside, they can’t climb out. We have heard that electronic mouse traps work really well, they use the electrocution method of killing mice.