If your ornamental plants and trees seem healthy one day but die the next, you may have a problem with field mice, known as voles. A quick examination of the stem of the plant near the base should confirm whether you have a vole problem. Voles leave tiny teeth marks near the base of plants, and remove the root system. Fortunately, they behave in predictable ways. This makes them easy to stop before they enter your yard or flower bed.
Mow down tall grass to remove ground cover. Voles do not like to enter open areas. A well-manicured lawn will discourage a vole from feeding on your plants.
Turn your mulch in your flower gardens frequently with a pitchfork. This will help to break up any tunnels that voles may use to travel around flower beds.
Clear mulch rings back from trees by at least 3 feet. This will prevent voles from reaching the tree to chew on the trunk under the cover of mulch bark.
Rototill your soil between vegetable crops for cultivation purposes and to remove vole tunnels.
Place snap traps near vole tunnel entrances. Leave the traps unset, but baited for several days. Then set the traps. Bait the traps with cheese, peanut butter or apple slices.