Gophers are a common presence across California landscapes, representing one of the most frequent pest challenges for homeowners and agricultural producers. They are pocket gophers, burrowing rodents named for the fur-lined external cheek pouches they use to carry food and nesting materials. Gophers are herbivores that spend almost their entire lives underground, systematically damaging lawns, gardens, and infrastructure as they forage and build extensive tunnel systems. Their constant activity causes significant destruction to plant roots and irrigation lines.
California’s Pocket Gopher Species and Range
California is home to several species of pocket gophers, all belonging to the genus Thomomys. The Botta’s pocket gopher (Thomomys bottae) is the most widespread, found in nearly every habitat type, from coastal areas to mountain valleys and agricultural fields. Their distribution is limited primarily by barren deserts, rocky terrain, and high alpine elevations where the soil is too shallow for tunneling.
Pocket gophers are often mistaken for moles or ground squirrels. Gophers are strict herbivores, feeding on roots, bulbs, and vegetation they pull into their tunnels, while moles are insectivores that primarily eat earthworms and grubs. Gophers possess powerful forequarters with large claws and small eyes and ears, which are adaptations for their subterranean life.
Unlike ground squirrels, which are frequently seen above ground, gophers rarely leave their complex tunnel networks. The primary evidence of a gopher’s presence is the fresh soil they push to the surface. A single gopher can establish a burrow system that spans an area of up to 2,000 square feet.
Identifying Gopher Mounds and Tunnels
The most reliable way to confirm a gopher infestation is to correctly identify the shape of the mounds they create. Gopher mounds are typically fan-shaped, horseshoe-shaped, or crescent-shaped, with the dirt piled asymmetrically. The opening through which the gopher pushed the dirt out is always plugged with soil, creating a soil plug slightly off-center of the mound.
Mole mounds, by contrast, are volcano-shaped or circular, and the entrance hole is usually found directly in the center of the pile. Gophers create their mounds as they excavate their main tunnel system, which generally runs between 6 and 12 inches below the ground surface.
A homeowner may also notice feeding signs where plants seem to have been pulled under the soil surface. Gophers forage near the surface by digging shallow lateral tunnels, which they use to access roots and then plug up immediately after use. The main tunnel system is connected to these lateral tunnels, making the plugged hole on the mound the most direct route to the gopher’s home.
Strategies for Gopher Management
Successful gopher management requires persistence and a multi-pronged approach, as these rodents are highly territorial. For most homeowners, trapping is the most effective and reliable method for immediate removal. This involves locating an active tunnel by probing the soil 6 to 12 inches from the fresh mound’s soil plug. Once located, two specialized box or cinch traps should be placed facing opposite directions within the main runway.
Exclusion is a practical long-term strategy. Gopher baskets, made of galvanized wire mesh with openings no larger than one-half inch, can be placed around the roots of new trees and shrubs before planting. For perimeter protection, a barrier of one-half-inch hardware cloth should be buried at least two feet deep, with a few inches extending above the ground to block tunneling into the area.
Cultural practices can also make a landscape less appealing to gophers, such as reducing excessive watering, since they prefer moist, soft soil for easier digging. Some plants, including daffodils, castor bean, and gopher purge, are naturally avoided by gophers and can be incorporated into landscaping. Chemical control, using toxic baits or fumigants, is available but should be used with extreme caution, following all local regulations, due to risks to non-target animals.