Gophers - to Tolerate or to Eliminate?
As a biologist and a conservationist I believe I can recognize the important role most living organisms play in their natural environment. We may dislike ants crawling around on our kitchen counter but still understand their role as predators of other insects, as scavengers and recyclers of organic material, and as soil inhabitants that help turn and aerate the soil to keep it healthy. By the same token, we can recognize the benefit to a natural environment from the presence and hard work of gophers, but still get a nasty attitude about them when they decide the soil under our pride and joy - our front lawn - needs turning. You spent the whole weekend mowing, trimming, weeding, fertilizing, and otherwise pampering the beautiful bluegrass lawn, and step outside Monday morning to find several piles of dirt laying on top of the grass.
This is our quandary - we place the title of "PEST" upon any organism that occurs where we do not want it to be. While gophers obviously are of benefit when they tunnel in the soil there is a distinct conflict with our interest of an aesthetically pleasing landscape. So, we decide to eliminate them, and that is what I'd like to discuss here in this article about gophers.
To successfully combat the enemy you first must understand it, and the experience many a gopher-hunter has had has told them that gophers are a formidable foe. They are not easy to get rid of, and quite often you may be tempted to use some age-old methods that in reality are quite ineffective. Let me just mention those right off the bat so we can move on:
- Flooding the burrow with water - generally very ineffective. You may succeed in driving a gopher out of the burrow, but now you are faced with clubbing it to death. Flooding is not going to drown them in the burrow, and a flood of water running through the hollow burrows also risks causing the chambers to collapse, creating a pretty unsightly problem for your lawn.
- Gas cartridges - these give off an irritating or toxic smoke, but usually the gopher detects the problem long before it has any serious effect on its health, and simply pushes a wall of dirt up to close off the chamber and keep the smoke out.
- Sound-emitting devices - you can't avoid the marketing of these magic boxes, that promise to "safely repel unwanted pests" of all kinds, by driving them off with ultrasonic sounds. From the conclusions of many university studies these are best labeled as modern-day snake oil. They have no effect on the presence of any kind of pest.
- Repelling with certain plants - there are no plants that will actually drive off gophers, although if you have a heavy cover of plants they don't like to eat they may go somewhere else. But, just planting a few garlic bulbs or castor bean plants around your garden will not affect them.
The methods that do work for established populations of gophers include trapping, poisoning, and fumigating, and we'll discuss each of these in a few minutes. First though, let's understand the gopher a little better.
The Life and Times of the Pocket Gopher
The name "pocket" gopher is given to these animals because they have fur-lined pouches in their cheeks that they use for carrying food. The pouch is NOT used to carry dirt, but the dirt is simply pushed along by the gopher with its front legs. They use their legs and teeth to dig the dirt out to create their tunnels, and then push the excess dirt out through little side tunnels and onto the outside surface of the soil or lawn.
Gophers are rodents, and there are over 100 varieties of them in the United States. They have long, hard front teeth called incisor teeth, they have tiny ears and small eyes, and tiny little tails that act as "feelers" when the gopher runs backward through its burrow system. Gophers are solitary animals, and you never have more than a single adult gopher living and working in a tunnel system. During breeding season males will be allowed into a burrow by a female, and of course the baby gophers are cared for by the mother until they are old enough to be off on their own. Otherwise, even though you may have many gophers living in your yard, and their tunnels may wander and curve around each other, they do not mix.
Gophers are vegetarians, and live almost entirely underground, feeding on roots of shrubs, trees, or landscape plants as well as plant material they gather during short sojourns above the surface and drag back into the burrow to eat or place in storage chambers. They may even chew on the lower trunks of small trees, girdling the bark and killing the tree. They may feed on lawns above ground, within a few feet of their burrow opening for a fast retreat if danger approaches.
Gophers do not go into hibernation, but instead are active year round. Even when the ground is covered with snow the gophers will tunnel at the surface of the soil, and these surface mounds can be seen easily when the snow melts away in the spring. In warmer weather the main tunnels stay around 4 to 8 inches below the surface, and may include over 800 feet of tunnels for a single gopher. Small side chambers are created for their nest area, for food caches, and for depositing their feces, since they cannot carry this material up to the surface.
I've got a hole or a pile of dirt - what made it?
Some other animals also burrow in the soil, and to avoid confusion here are some characteristics:
- Norway Rats - an open hole with well defined paths leading away from it.
- Ground squirrels - very large opening with dirt spilled out below it.
- Moles - evidence usually is surface tubes or tunnels created by the foraging mole.
- Gophers - dirt mound is "horseshoe" shaped, and on the inside of this horseshoe arc there will be a small "plug" of dirt about 2 to 3 inches across and usually of damper dirt.
The mound is created when the gopher pushes the dirt out of the chambers it is digging, and it digs a lateral tunnel to the surface and then pushes the dirt away from the opening, creating the arc or semi-circle around the opening. A fresh plug of dirt then is placed in the opening to close it off. The gopher may remove this plug at night and feed carefully at the soil surface, and then replace the plug when it crawls back underground.
So, how do I go about controlling gophers?
If you are bound and determined to try one of the easy ways then I encourage it. However, experience of many people who have done a lot of gopher control indicates these are intelligent animals that are not easily fooled. You might get lucky, and if you have only a single gopher working its magic in your yard, and you chase it to the surface by flooding its burrow (and your cat picks it off) then success might be in the works for you. Some people claim good results from using the gas cartridges too, but overall these methods are not particularly effective.
One other thought too, and that is to remember that just because you have eliminated all the gophers from your property does not mean that new ones won't move in very quickly. They are territorial, and once some ground is rendered free and clear of the competition new gophers may take over the vacated area, even moving into the burrow system left by a departed comrade. Gopher control often needs to be an ongoing process if your dahlias are to survive.
Gophers may certainly be the main course for several kinds of other animals, such as gopher snakes, owls, or the house cat with patience. Since the gopher does regularly come above ground to gather food the nocturnal predators such as owls and cats may be able to pick them off, and owls are even known to feed primarily on gophers, sometimes several each night. Gopher snakes are given their name because they will find their way down into rodent burrows, where they can attack and consume gophers. However, as one rodent expert from a California university put it, "one gopher could last the snake all summer", so expecting a snake to wipe out a gopher problem may be asking an awful lot from the snake.
The point, of course, is that encouraging these predators to live near you has its benefits, and since the gopher snake is non-poisonous then it will not be a hazard to people or pets.
For small areas it is possible to keep gophers out by putting in some sort of physical barrier, such wire fencing or hardware cloth of small mesh, metal or concrete barriers, etc. Obviously, for large expanses of yard and for landscaped areas already in place this may not be a reasonable option. If you want to install a barrier of this kind it should go at least two feet deep in the soil and be at least one foot above ground, so that gophers cannot climb over it.
This can be the most time-consuming and difficult way to control gophers, and relies heavily on expertise to place the traps correctly inside the burrow. The benefit to trapping is that you definitely know you got the gopher. There are two primary kinds of gopher traps, and either one may seem to be a rather gruesome way to kill the animal - the box trap and the wire trap - one strangles and one impales.
In either case the trap must be placed in the gopher burrow, in the hope that the gopher will try to move over or through the trap. What often happens, however, is that the gopher - which absolutely abhors changes in its burrow - detects the trap and fills it or covers it with dirt, setting it off and rendering it ineffective. When you dig into the burrow to place the trap you may not reseal the burrow properly, and the light coming in will alarm the gopher as well, causing it to seal off that chamber.
In order to be effective you are going to have to do some digging, and obviously if the gophers are in your lawn this cure could be worse than the disease in its effect on the appearance of the lawn. You need to dig down until you expose a main tunnel, and place the trap carefully in the runway. Better results are with two traps, one facing each direction to intercept the gopher from whichever way he comes, and traps staked to the soil to prevent being dragged away.
If you are lucky and do trap some gophers, do not handle them with your bare hands. Most rodents have parasites on them such as fleas that you do not want on you. Use gloves and place it into a plastic bag for disposal.
4. Poison Bait
There are several kinds of poison baits on the market, and if you can get the gopher to eat it they will work pretty well. The drawbacks to baiting for gophers include:
- The use of poison bait around a yard may run the risk of pets or birds eating the bait, especially if the gopher pushes it back to the surface. If you use poisons you must be very certain to use it exactly as the instructions on the Product Label advise you to.
- Gophers may just not like the taste of the bait. While they do eat some grains, baits may be a foreign food to them and not a trusted material. So, they push it out or bury it. Also, they might just haul it off into storage instead of eating it, and your results could be in for a lengthy delay.
- Bait must be placed into the burrows, never on the surface of the soil since the gophers won't find it there.
- There is a possibility that another animal - cat, dog, or hawk - might eat a gopher that has consumed a large amount of bait, and that animal could also be poisoned. This is not a very likely occurrence, but it is possible.
Bait needs to be placed in the runway, by probing near the mounds of dirt on the surface until you feel the probe push into the hollow burrow. A small amount of bait is placed into the burrow and the hole closed with a plug of dirt to keep light out. Then, you just hope for the best.
This is the final method of control, and probably the most effective. It also is the one method that only Licensed Professionals are allowed to do, for the use of fumigation chemicals is restricted to trained and licensed people. The one product used for burrow fumigation is called "aluminum phosphide", and one major trade name of the product is called Fumitoxin. It comes as solid pellets that are placed into the burrow, the opening is closed, and the humidity in the burrow causes the pellet to disintegrate and release the toxic gas. The gas penetrates throughout the entire burrow system and does not alarm the gopher, so the rodent is killed before it is able to wall off the area the gas is coming from.
This method offers several advantages:
- No toxic bait is used or remains behind
- The pellet disintegrates completely in just a few days, and all toxic material dissipates and is gone
- The gophers die within the burrow and do not tend to come out above ground
- Any fleas or other parasites on the rodent are also killed
- Acceptance of bait or movement into traps is not a concern
Again, though, this must be done by a licensed applicator, but it works so effectively that you might consider it.
To eliminate or to tolerate - a good question. If the gophers are off in the woods or a meadow somewhere then they probably should be left alone to do their thing. But, if they are ruining a lawn or destroying a garden, or if their burrows present a safety hazard to ankles and feet on a playground or athletic field, then there may be a justifiable reason to control them.