Controlling Animal Pests in the Landscape
By Dr. Leonard Perry, Extension Professor, University of Vermont
Effective control of animal pests is possible though your success will depend
on your timing, method, and perseverance. A control that works for your
neighbor, or that worked for you last year, may not work this time around. You
may need to try a variety of methods and devices and, if first you don't succeed,
try again. Remind yourself that animals may be clever and smart, but humans
Here are some common animal pests found in the Northeast and some
recommendations for control. None of these are fool proof, but all are worth a
try to control pesky animals.
MICE AND VOLES: Although these rodents look similar and cause similar
damage, they are only distantly related. Both live in grassy areas and leaf mulch
and travel in tunnels. They feed on any vegetation, including bulbs and tubers,
as well as bark on young trees and shrubs. Exclude them with barriers or trap at
main runways with peanut butter bait or vitamin D (death results from calcium
imbalance). Other repellents such as castor oil may help, as will cats or dogs.
If using a common poison bait trap or packet, be aware that cats or other
animals may be attracted to the trap to feed on the bait, or birds and other large
animals may be inadvertently killed by feeding on a poisoned small animal.
MOLES: Moles live in tunnels that, while helping to aerate soil, also provide
passageways for other animals and may cause excessive soil disturbance and
plant upheaval. Although moles help by eating insects like grubs, they also
hurt by eating earthworms. Control them by eliminating the insects they feed on
or trap as you would voles.
CHIPMUNKS: This rodent lives in tunnels or burrows and is adept at running
up trees and shrubs as well as along the ground. Chipmunks feed on seeds,
nuts, fruits, roots, bulbs, and despite their tiny size they can uproot new
plantings. Trap them using peanut butter, oats, nut meats, or sunflower seeds.
Spray repellents on bulbs, or place jagged shells or stones in the holes when
you plant bulbs. Fine-mesh plant cages will keep them out. Or get a cat or two.
TREE SQUIRRELS: Squirrels are an occasional problem as they like to nest in
trees and will feed on fruit, nuts, insects, bark, and seeds. Protect new plantings
with cages. Squirrels can be trapped and released using sunflower seeds,
peanut butter, and raisins as bait.
RABBITS: Rabbits are a serious problem not just in the Northeast, but
throughout the entire country. They live in grassy areas and thickets, feeding on
vegetables, flowers, and tree bark during winter. They are active during the day
year round in most areas. Your best bet is to fence them out with chicken wire
or hardware cloth cages placed higher than snow level. Inflatable snakes or
repellents, such as those used for deer, also may help.
GROUNDHOGS (WOODCHUCKS): These rodents (related to rats and
squirrels) cause only occasional problems in the northern states, mainly to
herbaceous plants. They live in burrows with two or more openings with
mounds at entrances. You can find them feeding in early morning and late
afternoon on grass, tender vegetables and flowers-- especially pencil-thick
stems like phlox, and occasionally on bark. They don’t “chuck” on wood, this
name coming from a native American name for this animal.
Your best bet is to trap them live (if legal) or fence them out with a three-foot
high fence. Bury several inches in the ground to prevent them from tunneling
under. You also can repel them with taste sprays applied to desirable flowers
or by placing oily substances at hole entrances. If all else fails, you could insert
poison gas cartridges in their holes and cover to kill. Don’t use the latter
around buildings, though, which they like to make holes alongside or under.
Live traps with release of animals a distance away may not be the best
alternative as you may catch non-target animals. For example, you may catch
domestic cats, or even skunks. Your community or state also may have
regulations against relocating certain wild animals such as woodchucks. Be
sure to know your local wildlife laws before you act. If trapping large live
animals, use caution to prevent being bitten as many carry communicable
diseases such as rabies.
Snap or leg hold traps are banned in most areas, though even if permitted they
are not a good choice as it is a cruel and inhumane way for any animal to die.
There's also a good chance that you could catch a pet or worse, injure a child.
Shooting is usually not permitted, and especially not in populated areas. You
may choose to hire a wildlife specialist to catch and dispose of such large
SKUNKS: Skunks live in rural, wooded areas where they feed on insects, small
rodents, fruits, berries, and other vegetables. They are actually more of a
nuisance because of their smell than from eating flowers, although they can
carry rabies. Fence them out or trap (if legal) as you would groundhogs. If
trapping live, bait with sardines or cat food. Be sure to wear protective clothing
and eye goggles when handling skunks, and cover the cage with a tarp when
RACCOONS: Like skunks, raccoons generally are not a problem in flower
gardens although if you have corn, be on the lookout for these masked
marauders. They live in wooded rural or lightly populated areas in natural
shelters such as hollow logs or near water. They feed on insects, small animals,
grains (especially corn), seeds including bird seeds, vegetables, and other plant
materials. Keep them out with a wire fence (about four feet high with another
foot buried in the ground) or electric fencing, or trap (if legal) as you would
DEER: Deer are a serious problem throughout the country, even in populated
areas. Being quite intelligent, with few natural predators and strict control laws,
they can be difficult to control. Deer prefer wooded areas and tall grass and
thickets. They eat most plants and the bark of woody plants.
Many deer controls are available, including various taste and smell repellents
(deer have a keen sense of smell); light or noise emitters (must be moved often
as deer are smart and learn quickly); or an electric fence baited with peanut
butter (one taste won't kill, but will deter deer). A key with such repellents is to
move them, or rotate among various ones, every few days.
The best and often only solution, particularly if many deer and they are hungry,
is exclusion with three-wire triangular or slanted fences, or eight- to ten-foot
high deer fences of woven wire mesh or heavy fishing line strung at two-foot
intervals up the posts. If using the latter, flag the lines as deer can't see well and
will try jumping through. For narrow or small gardens, a lower fence 5 to 6 feet
high usually works as deer are afraid of getting trapped inside.
DOGS: Dogs can devastate gardens by running and romping. They also dig up
soil and plantings and leave droppings. Keep them out with fences or repel
with plant sprays designed specifically to deter dogs. Tie up your own dog or
use invisible fencing to keep it from getting into areas you want to protect. Ask
neighboring dog owners to keep their pets out of your yard.
CATS: While cats usually are good at keeping small rodent populations in
check, they can be a problem if they dig up new plantings. Use repellents or lay
chicken wire on new beds.
Distribution of this story is made possible by University of Vermont Extension and New
England Grows - -a conference providing education for industry professionals and
support for Extension's outreach efforts in horticulture.