Gophers in California were the bane of my existence. A perfectly healthy rose bush one day would be dead the next after a gopher had chewed away the roots. My husband used to run the hose down a gopher hole and the water could run for hours, through the underground tunnels. Occasionally a gopher would pop its head up, but not often. They seem impossible to get rid of--I even bought an electric gadget that supposedly emitted a sound that discouraged them. A gopher burrowed right under the sign! Good luck with yours!