Control Methods for Individual Vertebrate Pests Jeanette Stehr-Green and Judy English, Washington State University (WSU) certified Clallam County Master Gardeners Vertebrate and Identifying damage Birds: Droppings; deep triangular peck holes or slashes in larger fruit; smaller fruit eaten whole
Recommended methods of control − Exclusion (netting that reaches ground or is gathered around trunk) − Scare tactics (must be frequently changed) − Chemical repellants (active ingredient methyl anthranilate [food grade])
Cats: Plants uprooted; feces buried in soil
− Exclusion (chicken wire at ground level or just below soil through which plants can grow; mulching with stone or pebbles; single or double strands of electric fence at low voltage) − Resistant plantings (Rue? Marigolds?) − Scare tactics (motion-activated sprinklers, dogs)
Deer and Elk: Leaves and twigs ripped from plants leaving a ragged edge; annuals pulled out of the ground; damage to larger trees extending only to about 8 feet; broken branches and torn bark from animal rubbing tree trunk (~4 feet high)
− Exclusion (8 foot fence around garden; lower fences effective if slanted − − − −
outward, double, or made of solid material; fencing individual plants) Scare tactics (must be frequently changed) Chemical repellants Resistant plants (wdfw.wa.gov/living/deer.html) (however, young and hungry deer will nibble on anything) Hunting
Dogs: Digging up plants; holes in lawn or − Exclusion (fencing of entire garden, fencing of individual plants, chicken garden wire at ground level, mulch that is uncomfortable to walk on) − Resistant plantings (vigorous plants that resist breakage; thorned or prickly bushes but avoid long thorns) − Important to explore reason for garden damage (dog in need of attention and exercise; digging for prey; trying to escape to mate) Moles*: Large, volcano-like mole-hills that they push up periodically along their tunnel systems; probably do not intentionally damage plants; plant damage due to voles which often use the mole’s tunnel systems
− Exclusion (wire mesh bottoms on raised beds and wire mesh baskets around bulbs or roots of plant)
− Scare tactics (watch dog or cat) − Chemical repellants (castor oil-based repellants effective in Eastern Washington species but not proven on Western Washington species) − Trapping (must be buried along active runways) − Poisons (hard, pelletized baits don’t work; newer gel and worm-shaped baits that better mimic natural food sources more promising) − Hunting or otherwise killing (observing active digging on molehill, stunning, and digging down to catch animal)
Mountain Beavers: Damages plant by clipping off stems and branches, leaving 2 inch stubs; destroys more vegetation than it eats; stacks cut vegetation near burrows
− Exclusion (fencing selected plants; fencing entire yard with rabbit-proof
Rabbits: Twigs on trees and shrubs clipped cleanly at a 45 degree angle; bark on lower stems and branches gnawed away, leaving parallel grooves in the wood
− Exclusion (chicken wire fence at least two feet high with bottom edge
Raccoons: Attack fruit, nuts, and vegetable crops
− Exclusion (with two-strand electric fence with the first wire about 6
Rats and Mice: Trails through vegetation; gnawing at base of trees/shrubs
− Removal of wood piles, dense vegetation, and rubbish around garden − Removal of food sources − Baited traps (mouse favorite: mix of peanut butter and rolled oats)
Tree squirrels: Attack fruit, nuts, and vegetable crops; strip, eat bark from tree
− − − −
Voles: Gnawed roots and root crops (small grooves left by the 2 large front teeth); girdling of tree trunks extending to just above soil line; if other food unavailable will girdle trees and eat bark
− Removal of shelter and hiding places − Trapping (mousetraps baited with peanut butter or pieces of apple set in
fence; two wire electric fence)
− Trapping
tight against ground or buried a few inches; hardware cloth mesh cylinders; commercial tree wraps) − Removal of shelter and hiding places − Hunting (Rabbits are classified as game animals; therefore, regulations regarding hunting and trapping are in place.) inches from the ground and the second wire 6 inches higher; rodent guards on trunks of fruit trees) − Trapping
Exclusion (rodent-guards on trunks of fruit trees) Chemical repellants Cage trapping Hunt but native squirrels protected by law
their runs)
− Poisons (rodenticides)
* Townsend or Pacific mole has litters of three or four in April; at 3-4 weeks old young moles leave nest for own territory; lifespan about 3 years
6/01/2015