Gophers push soil out of their holes, creating distinctive fan-shaped or crescent-shaped mounds on the surface. The mounds are 12 to 18 inches wide and 4 to 6 inches high. After digging a mound, the gopher may close up the hole with a soil plug. One gopher can create several mounds a day (or up to 200 mounds a year). Gopher tunnels are about 3 inches in diameter and do not follow a pattern; they are located a few inches to 5 feet below the surface and run for hundreds of yards. You know you have gophers when your plants are damaged in areas where you have the fan-shaped mounds. Often, garden plants are pulled bodily down through the soil into the tunnels.