Raspberry plant pests can infest your plant, weakening the berry canes and eventually killing the plant if not treated. Animals can steal your fruit crop. Combining biological and chemical control methods helps remove the pest threat with less damage to your plants.
A number of insects eat your raspberry plant, damaging the leaves and berry canes. Raspberry insect pests include the raspberry horntail, a wasp; the rose stem girdler, a type of beetle; the raspberry crown borer, a moth; and the tarnished plant bug, a winged insect.
Use an insecticide approved for use in your area. Utah State University Extension suggests products containing diazinon, malathion or rotenone. Remove growth that appears to have insect infestation, since you'll also remove a great deal of pest or insect larvae, slowing the rate of infection. Burn the affected growth or take it to a landfill. Do not use insecticide while your raspberries are blooming or just before they bloom. This kills pollinator insects and reduces your berry crop greatly.
Squirrels and rabbits eat raspberry bushes, as do deer and raccoons. Encase the plants with netting or use a pest repellent. Watch the plants to see what wildlife ventures nearby, and then look for a natural pest repellent that deters the animal thief.
Plants that have insect or animal predators have holes or bite-marks in the leaves. The tips of berry canes die back or begin to wilt. Canes turn brown and wilt into a crook-shape. If you cut open wilted canes, you might see insect larvae inside. You also might see animals lingering near the plants or view insects on the leaves.