Controlling Gophers
By Bob Chapman
The gopher is an amazing animal. He's called a "pocket" gopher because he can store food in pouches, or pockets, in his cheeks to carry back to the nest or food storage chamber. Contrary to popular belief, the pocket gopher has good eyesight even if he's predominantly a night feeder. His sense of smell is highly developed and his body is especially well adapted to living his entire life in underground burrows. The gopher can turn himself completely around in the burrow in the twinkling of an eye and has lips in back of his teeth so he doesn't swallow the dirt he's digging in. In addition to the ability to dig with his teeth, all 4 feet are used when burrowing underground. The front feet loosen the dirt and the hind feet kick it out of the burrow, making those telltale unsightly mounds. He uses his nose to tamp soil into place when constructing tunnels, the nest, or food storage chambers.
A gophers lifestyle
Pocket gophers are solitary and territorial creatures. The only time there is more than one gopher in a burrow is during the mating season or when the female is rearing her young. If by chance a gopher invades another's burrow the two will fight until one is driven out or is killed. Owls are the gopher's greatest natural enemy, others being snakes, hawks, foxes, coyotes and cats. He is most vulnerable to capture when he's foraging or searching for new quarters. This searching takes place when the female kicks out the nearly grown young, when the food supply is exhausted, or when looking for mates. They typically move 1000 feet or more looking for unoccupied territory to claim for their own.
Damage caused by gophers
Pocket gophers can be very destructive in the garden. They prefer plants that have fleshy roots, lawns, dichondra and gazanias, to name a few. However, they are only selective when food is plentiful. The damage inflicted by gophers includes eating roots and stems below ground and even reaching out of the burrow to pull over and devour choice plants. A hidden source of trouble to the plant is the exposure to the root zone of more air from the gopher's tunnels than the plant can tolerate. Happily, most ornamental trees and shrubs can survive attacks by gophers. It's the exceptions that can be exasperating to the gardener.
Getting rid of gophers
- Poisons. Licensed professional applicators use strong, restricted poisons to control the pests. Poison grain is used to control gophers, but it's risky. The poison commonly used is strychnine, one of the most toxic poisons known, and its use has to be controlled. It should be stored in a locked cabinet out reach of inquisitive children. Gophers can push the poisoned grain out of the ground if not properly applied and birds, pets and children can eat it Often a gopher will only consume a small portion, become sick, recover and then is 'bait-shy'.
- Traps. The best bet for gardeners is the U-shaped, spring-type Macabee trap. But you can't just put the trap in the ground and expect to catch a gopher. They have an extremely well developed sense of smell and hearing. They can tell if their burrow has been disturbed.
Locating the tunnels
To be successful in trapping them knowledge of their underground habitat is necessary.
- Main runs. The gopher has one or more main runs, 2 to 4 inches in diameter, usually 2 to 18 inches below and parallel to the surface. Lateral runs are likened to the branches of a tree. They are dug at various angles to the surface from the main run and are used to push out soil accumulated from burrowing. They show up in our gardens in the familiar fan-shaped mounds, with the access hole at one side of the fan.
- Pop holes. "Pop holes" are those dug in order to forage on the surface and when finished eating the gopher plugs the hole with loose soil. Pop holes lead straight up from the main run. Locating the pop holes tells where the main run is located.
- Open holes. When the gopher dies or the burrow is vacated, these plugs get washed out by irrigation or rain, leaving open tunnels in the ground.
- Other tunnels Other tunnels are dug for nest sites, food storage areas, drainage tunnels to carry away excess water and "potty holes".
Finding the "main run"
Use a sharpened broom handle or a sharp metal rod to locate the main run. Find the run by pushing the probe into the ground until it "gives" and suddenly drops 2 to 4 inches. The key here is ensuring that you have located a main run, as the gopher may not come back to a lateral for some time, if ever. Using a freshly washed shovel (remember that gophers have an excellent sense of smell) dig down to uncover the tunnel.
Setting the traps
Two traps are needed for each hole that's opened. Attach a 3-foot piece of flexible wire or small chain to each trap at the spring end. Because of the gopher's keen sense of smell that traps have to be free of human odor. Wash the traps and wire or chains in boiling water. Use freshly washed cotton gloves when setting the traps.
After the run has been opened, set the trigger and push a trap back into one opening of the run as far as you can reach and then place the other trap in the other hole. Drive a stake into the ground and fasten the wires to it. Leave the hole open. This is important, as the gopher senses that his abode is disturbed and a hole is open. Pushing dirt towards the hole with his front feet he trips the trap while trying to close up the open hole. If he smells the human odor he may simply plug the tunnel without reaching the trap and efforts to catch the little rascal are foiled. If pets or children are in the area cover the open hole with a board and put a heavy weight on the board.
Check the traps daily. If not successful and you have not caught the gopher, locate another run and repeat the above process.
Fairy tales about ridding and preventing gophers
- The popular conceptions of gassing, drowning, noisemakers, using "gopher plants", etc. seldom work. If gas bombs are used the crafty animal simply plugs his burrow at the first whiff. Attaching a hose to an exhaust pipe is great for the oil companies but has little effect on the gopher. Most of the gas escapes into the porous soil anyhow. Trying to drown them in porous soils is simply a waste of water and besides most gophers have already anticipated this and have dug one or more drainage tunnels.
- Gopher plants (Euphorbia lathyris) do not deter the gopher. He'll make a meal of these as well as any other plants.
Proven methods of preventing gophers
- In areas where gophers are endemic and control is very difficult, dig a trench 2 feet deep around the perimeter of the garden or lawn and bury rabbit wire upright, leaving 6 inches projecting above the ground.
- Fashion wire baskets around the root ball of plants prior to planting to prevent gophers from reaching the roots.
- Raised flowerbeds lined with rabbit wire on the bottom and then filled with soil are used to thwart gophers.
- And finally, if planting a new lawn, burying small mesh chicken or rabbit wire about 4 inches below the surface of the soil will prevent the extensive damage that gophers can cause to lawns.