STEPS TO TAKE TO MITIGATE THE INTRUSION OF GOPHERS AND MOLES IN YOUR YARD
Plant Vegetable/flower gardens in raised beds. Place ONLY "galvanized hardware cloth" screening material, securely fastened, to the bottom of the bed to prevent intrusion.
Place all flowers in Planter Boxes, clay pots, or encase in "gopher baskets". Do not use chicken wire as a gopher "can and will bite" through it.
Studies show that gophers/moles will be deterred from digging through rock 1" in diameter.
You can dig trenches three feet deep and one foot wide and fill it with rock to deter lateral entry into specific location in your yard.
This, however, would not prevent them from moving into the area above the ground.
Other Animals are your friend
Some Cats and Dogs will actively hunt gophers and moles
Birds of Prey will also hunt gophers and moles. If feasible, install raptor stands on your property
Galvanized Hardwear Cloth
Install between lawn areas.
This will prevent the gophers/moles from penetrating the law area.
You must ensure that the installation of the wire is done correctly.
There can be no gaps in the wire
It is unrolled similar to carpet
Wire comes in 3" and 4" widths
The widths must overlap each other by 6" and be securely pinned with lawn pins
The edges of the wire must be secured to prevent gophers/moles from pushing dirt up around concrete, rock borders, etc.. This is commonly overlooked and defeats the entire purpose of placing the wire under the lawn.
Make sure you have conveyed this to your landscaper.
Additionally, do not allow sod to be placed over the wire until you have inspected it to ensure proper installation
California Department of Fish and Game
Fur Nuisance Trapper License # 64687.