Pocket gophers represent one of the most common and destructive subterranean pests encountered by Arizona residents. These rodents, primarily the Botta’s pocket gopher (Thomomys bottae), spend nearly their entire lives underground, creating extensive tunnel systems across yards and gardens. Their burrowing activity directly damages the roots of cultivated plants, while their sharp incisors also gnaw through buried irrigation drip lines and utility cables. Controlling these pests is important for protecting property value and outdoor infrastructure, given the reliance on carefully maintained landscaping and limited water resources in Arizona’s arid environment.
Identifying Gopher Activity and Damage
The most distinct sign of gopher activity is the presence of crescent-shaped or fan-shaped mounds of loose soil scattered across the yard. This mound shape is created as the gopher pushes dirt out of a lateral tunnel, which is then plugged with soil from the inside, leaving no open hole visible on the surface. This characteristic plugged mound differentiates gopher activity from that of moles or ground squirrels.
Damage to plants occurs when gophers feed on roots they encounter while digging or when they pull entire plants down into their tunnels. Homeowners often notice newly planted shrubs or trees suddenly wilting or sinking into the ground, indicating a severed root system below. Gnawing on underground irrigation components, especially soft polyethylene drip lines, leads to leaks and wasted water.
Exclusion and Non-Lethal Deterrents
Preventing gophers from establishing a presence is the most effective long-term strategy for protecting high-value landscaping. Physical barriers can be constructed using galvanized hardware cloth with a small mesh size, typically 1/2-inch or 3/4-inch, which is too small for the rodents to pass through. For protecting the perimeter of a garden or flower bed, this mesh should be buried vertically to a depth of at least 18 to 24 inches to block the gophers’ main tunnels.
When planting individual trees or shrubs, the roots can be protected by planting them in hardware cloth baskets that extend down and slightly above the soil line. This wire barrier prevents the gopher from accessing the root ball immediately after planting. Methods such as vibrating sonic spikes or applying castor oil-based repellents into the tunnels are considered to have limited effectiveness in providing reliable, long-term deterrence.
Active Removal Methods (Trapping and Baiting)
Lethal trapping is the most efficient method for immediately removing a gopher, especially for a contained residential infestation. The first step involves locating the main runway, which is 6 to 12 inches below the surface, by probing the ground a few inches away from a fresh mound’s plug. A specialized gopher probe or a simple 1/4-inch steel rod is inserted until it drops suddenly into the open tunnel.
Once the main runway is located, the area is excavated carefully to expose the tunnel, and two traps are set inside the opening. Body-gripping traps, such as the Macabee or box traps, are placed facing opposite directions to intercept the gopher regardless of which way it approaches to plug the breach. Traps should be secured with a piece of wire attached to a stake above ground to prevent the gopher from dragging the trap deeper into the burrow system. After the traps are set, the excavated hole should be completely covered with soil or a board to prevent light and air from entering, which would otherwise alert the gopher to the trap’s presence.
Toxic baits, or rodenticides, are typically grains coated with a poison like strychnine or zinc phosphide. These products must be applied deep within the active tunnel system using a specialized probe or bait applicator, never scattered on the surface. Subterranean placement ensures the gopher consumes the bait and minimizes the risk of non-target wildlife or pets encountering the poison. Because gophers are solitary, removing the individual responsible for the active mounds often resolves the immediate problem.
Legal Restrictions and Safety Precautions for Arizona Residents
While pocket gophers are classified as non-game animals by the Arizona Game and Fish Department, state law allows for their control by any legal means when they are causing property damage. Residents can use traps and approved toxicants to manage infestations on private property. Before using any chemical control, check local municipal or county ordinances, as some urban areas may restrict the use of certain fumigants or chemicals near water sources or residential boundaries.
Rodenticides carry a substantial risk of secondary poisoning to non-target animals, including family pets and local predators that might consume a poisoned gopher. For this reason, the Arizona Cooperative Extension recommends against using baits in small residential settings where the risk to domestic animals is high. Homeowners who choose to use toxicants must ensure the products are stored safely away from children and pets and applied strictly according to the product label instructions.