Two field trials were conducted to determine the effectiveness of anticoagulant baits in pocket gopher (Thomomys bottae) control. In the first trial, burrow systems were baited once with chlorophacinone 0.005% on rolled oats and embedded in paraffin to form a wax block. The systems were arranged in a one systemwide line bordering a clean vineyard. Infestation of the vineyard was prevented for 2 months; after that, gophers did bypass the barrier of treated systems and entered the vineyard. In the second trial two anticoagulant baits, chlorophacinone 0.005% on rolled oats and embedded in paraffin, and diphacinone 0.0052% on various grains and embedded in paraffin, were compared to strychnine-treated 0.29% whole wheat grain bait. Fifteen individual gopher systems were baited in each of three replications and monitored for 8 1/2 months. Both of the anticoagulant paraffin block-type baits achieved significantly greater long-term gopher control than the strychnine-treated loose grain bait.