Gophers often destroy yards and gardens by burrowing tunnels in the ground and feeding on cultivated plants. They also damage other items such as water pipes and sprinklers. The tunnels disturb the appearance of the landscape, and any water leaking from pipes and sprinklers may erode the soil. You may be able to kill gophers by feeding them poison.
People may recommend using common food items to kill gophers, but these home remedies don't usually work. Food items believed to kill gophers include chewing gum and chocolate laxatives. The University of California at Davis conducted an experiment whereby captive gophers were fed these food items. Neither chewing gum nor chocolate laxatives killed them. In fact, the captive gophers actually developed a sweet tooth. People may think these items kill gophers because they see no signs of gophers after spreading these items in an infested area.
The most common gopher bait is grain treated with strychnine, a poison that occurs naturally in plants. A strychnine concentration of 0.5 percent can usually kill a gopher with just one feeding. This concentration may not kill large gophers, but you can't get a higher concentration for home use. If gophers don't eat the bait, it breaks down within days in damp soil so it doesn't harm non-target animals.
People usually use anticoagulant baits for rats and mice, but you can also use them for gophers. With diphacinone as the active ingredient, the bait kills gophers slowly in five to 10 days. The bait usually comes in a solid block form that contains the poison and grain. An anticoagulant bait is safer because it doesn't immediately kill the animal that feeds on it. According to the University of California at Davis, this type of bait controls gophers effectively.
To be successful, you have to place the bait in the appropriate location such as the gopher's main tunnel. To find this tunnel, stick a gopher probe into the ground near the gopher's soil mound. You can obtain a gopher probe from a garden center. Don't place poisoned bait on the ground surface, where it can harm pets and other non-target animals.