Strychnine, formulated on milo, barley or wheat, is a widely used toxicant but is highly toxic and potentially hazardous to all wildlife. It usually is labeled as a Restricted-Use Pesticide. In some studies, zinc phosphide has been less effective than strychnine. The blocks provide long-term control because the bait remains effective after killing resident gophers so that invading gophers also are eliminated. To poison pocket gophers, place the bait in their tunnel systems by hand or with a burrow builder machine.
Place bait into a burrow system by hand after opening the main tunnel or with a hand probe.
To place bait in the burrow system by hand, locate the main tunnel by digging with a shovel 12 to 18 inches from the plug side of the mound. Place the recommended amount of bait, following label directions, in each direction of the opened main tunnel and well into the system. Close off each tunnel with sod clumps and soil so gophers do not attempt to close the system and cover the bait with soil. Place quantity of bait into main tunnel with a long-handled spoon. Seal tunnel with sod, do not cover bait with soil.