Introduction

Pocket gophers (Figure 1) are one of Idaho’s most prevalent and destructive vertebrate pests. These burrowing rodents are named for their fur-lined, external cheek pouches or pockets in which they carry food and nesting materials. Pocket gophers are 5–14 inches long, range in color from black to brown, and have small eyes and ears, flat heads with short necks, and large claws on the front paws.

Gopher burrows consist of a main tunnel and several lateral tunnels. As they dig their tunnels, pocket gophers push soil to the surface and deposit it in crescent- or horseshoe-shaped mounds that are 12–18 inches wide and 4–6 inches high (Figures 2 and 3). A single burrow system can cover 200–2,000 square feet. Gophers can create several mounds in one day. Fresh soil mounds indicate recent activity.

Gophers consume plants or plant materials including green, succulent vegetation, roots, bulbs, tubers, grasses, seeds, flowering plants, tree roots and bark, and pasture plants with palatable roots such as clovers and alfalfa.

Pocket Gopher Control

Restricting Access to High-Value Plants

Fences can be installed around shrubs, trees, and gardens. Use ½- to ⅜-inch mesh wire and bury it 2 feet deep in soil, leaving 1 foot aboveground. Gravel can be laid around cables and sprinkler lines can be encased in metal.

Flooding

Water from a hose inserted into a gopher hole can push the gopher aboveground to be trapped or otherwise humanely terminated.

Trapping

Traps can be placed in the main or lateral tunnels. Locate fresh soil mounds as shown in Figure 2 and dig with a shovel, following the plugged lateral tunnel until you reach the main tunnel. Place traps in the tunnel in pairs, facing in opposite directions. Set traps according to the manufacturer’s directions. Farm supply stores sell a variety of traps. Box style traps are typically the easiest to use.

Connect traps to stakes with wire to prevent gophers from moving traps deep into the burrow system and predators from taking the gopher and trap. Some traps work best if light is excluded from the burrow by covering the entrance with soil or plywood.

Baiting

Poisonous rodenticide baits come in grain and pelletized forms (Table 1). Locate the main tunnel by probing about 8–12 inches from the gopher mound to a depth of at least 4 inches. When the probe is over the main tunnel, it will easily drop about 2 inches. Dispense the correct amount of bait into the probe hole using a long spoon or probe, then close the hole. Handheld gopher baiting equipment (Figure 4) allows the user to probe for the tunnel and place a premeasured amount of bait in the burrow system.

Table 1. Rodenticides for use with hand baiting.

Rodenticide	Legal Constraints	Timing	Comments
Strychnine	Cannot be used aboveground.	Early spring through late fall.	Very effective and lethal in a single feeding. Secondary poisonings may occur if animals feed on gophers killed by strychnine.
Zinc phosphide	Cannot be used aboveground. Some formulations are restricted-use products.	Early spring through late fall.	Use a handheld probe and baiting tool to dispense bait underground in the main tunnel. Do not get this product wet.
Rozol	For noncrop use only. Some formulations are restricted-use products.	Early spring and late fall.	Use a handheld probe and baiting tool to dispense bait underground in the main tunnel.

After baiting, level gopher mounds or mark treated burrows with flags. These practices make it easier to detect new gopher activity and retreat as necessary.