Common Pests of the Pacific Northwest

By Kelly Roberson

Have you noticed tunnels in your yard, yellow leaves, and half eaten vegetables in your garden? You may be aware that you have animal and insect pests, but aren’t sure what they are or what to do about them. Insect and animal pests are everywhere; however some regions attract specific types. Below are the most common animal and insect pests of the Pacific Northwest region.*


Both shell-less slugs, which are members of the snail family, and shelled snails love the moisture of the Pacific Northwest region and leave behind a slimy trail of damage as they eat through leaves and vegetables. Although the destruction tends to be cosmetic, a severe infestation of either snails or slugs can wreak enough havoc to kill a plant.

  • Designation: nuisance and harmful
  • Remedy: There are several options to get rid of slugs and snails. You can start by applying a slug/snail removal bait product, such as Corry's Slug & Snail Killer; these easy-to-use pellets work for two weeks. Also consider putting a Corry's Copper Tape Barrier around plants; the copper will lightly shock and deter insects.
  • There are more labor intensive methods available, too. You can remove slugs and snails from plants by hand first thing in the morning, and then drop them in a pail of soapy water to kill them. Repeat until the pests are no longer present. Finally, encourage birds and beneficial insects by including plants suitable for the region and maintaining a healthy landscape.

Although slugs can be picked off by hand, it's a tedious, time-consuming task. Pellet bait remedies can help keep these mollusks from destroying plants.


Pests that target inside and outside plants, aphids are small, long-legged insects that feed on leaves. They leave behind a sticky residue that yellows leaves and stunts plant growth.

  • Designation: nuisance and harmful
  • Remedy: Encourage beneficial insects, such as lacewings and ladybugs, by including plants suitable for the region and maintaining a healthy landscape. Protect gardens with row covers and remove when plants are healthier. Finally, rinse plants with daily doses of water. If this gentle approach fails, you can also apply a product, such as Sevin, which can be quickly sprayed on infected plants.


Often mistaken for a mouse, a gopher or a mole, a vole is a small rodent that burrows and eats plants, nuts and roots. The damage caused by voles is three-fold: They girdle trees and seedlings, destroy plants in garden beds, and create extensive tunnel systems that can ruin lawns. In addition, voles are prolific breeders; they can take over landscapes with large infestations.

  • Designation: nuisance and harmful
  • Remedy: Protect trees with wraps, and then adjust the wraps as trees grow. Be sure to maintain a healthy, debris-free yard and use locally-approved baits according to directions.

*Remedy time and difficulty will vary by the size of the garden or yard; most involve taking simple steps. Follow all product label recommendations to ensure the greatest chance of solving the problem.