Pocket gophers are small, solitary rodents that create extensive underground tunnel systems, causing significant damage to landscapes and gardens. These burrowing pests feed on plant roots, tubers, and bulbs, leading to dead patches of vegetation and compromised soil integrity. Effective management requires a multi-step approach focused on accurate identification, efficient removal, and long-term exclusion to prevent reinfestation.
Recognizing Gopher Signs
The first step in control is confirming the pest is a pocket gopher, as their activity is often confused with that of moles or voles. Gopher mounds are the most distinct indicator, characterized by a fan or horseshoe shape of excavated dirt pushed out from a lateral tunnel. The actual entrance is often plugged with soil and located off to one side. A fresh mound contains dark, loose soil, indicating recent activity.
This appearance contrasts sharply with the conical, volcano-like mounds created by moles, which typically have a visible plug in the center. Gopher tunnel systems are generally deeper (six to twelve inches below the surface) and lack the raised surface ridges characteristic of mole foraging tunnels. To locate the active main runway, use a thin probe between the newest mounds. The main tunnel is found when the probe suddenly drops about two inches, indicating a hollow space.
Trapping and Mechanical Removal
Mechanical trapping is the most reliable non-chemical method for gopher control. The most common traps are spring-loaded, two-pronged models (like the Macabee or Cinch) or choker-loop wire traps. Success depends entirely on placing the trap correctly within the main runway, not in the superficial lateral tunnels.
The process begins by excavating the tunnel entrance where the probe located the main runway, creating a small opening. Two traps should be set, facing opposite directions, to intercept the gopher regardless of its travel direction. This dual-trap setup maximizes capture chance.
Baiting is not always necessary, but food like carrot or peanut butter can be placed behind the trigger to encourage entry. Once the traps are positioned, the opening must be covered completely with soil or plywood to exclude all light. Gophers instinctively plug breaches in their tunnel system, and excluding light encourages them to approach the trap.
Chemical and Gas Control Methods
Chemical control involves applying toxic baits directly into the active tunnel systems to minimize risk to non-target animals. Acute toxicants, such as grain baits containing 0.5% strychnine or 2.0% zinc phosphide, are lethal after a single feeding. These baits must be applied using a specialized probe or funnel to ensure they are deposited deep within the main runway and not spilled onto the surface.
Anticoagulant baits, such as those containing chlorophacinone or diphacinone, cause internal hemorrhaging over several days. The primary risk is secondary poisoning if a pet or predator consumes a poisoned gopher. Therefore, these methods are often restricted in residential areas or require licensed professional application.
Fumigation methods, like gas cartridges or smoke bombs, are generally less effective because gophers quickly sense the intrusion and plug off the burrow section. Newer pressurized exhaust machines inject lethal concentrations of carbon monoxide directly into the system, achieving higher efficacy rates by asphyxiating the pest. Highly regulated compounds like aluminum phosphide, which evolves phosphine gas, are restricted and typically reserved for licensed professionals.
Securing the Area Against Reinfestation
Once active gophers have been removed, implementing physical exclusion barriers is the most durable strategy against reinfestation. New individuals will move into vacant tunnel systems if they are not deterred. The best defense involves installing hardware cloth or wire mesh with openings no larger than 1/2 inch to create impenetrable barriers.
For protecting individual plants, wire mesh baskets should be installed around the root ball before planting. For garden beds or lawn perimeters, a subterranean fence made of hardware cloth should be buried at least 2 feet deep. The mesh should be bent outward at the bottom to form an L-shape to discourage tunneling underneath. Maintaining a well-drained, less-watered landscape also makes the area less appealing, as gophers are often drawn to soft, moist soil.