’Tis the season…for pocket gophers! While pocket gophers are actually active throughout the year, they become more evident to us as the snow melts off and the weather gets warmer. Our burrowing friends ramp up their foraging and tunneling activity. The more plentiful food sources are, the shorter the tunnels and the more surface disturbance. For sparser areas, they will tunnel long distances, their passageways being typically 6 inches to 24 inches deep, although nests and food storage chambers have been found deeper. Their favorite foods include dandelion roots, as well as alfalfa. It’s estimated 80 percent or more of alfalfa fields in northern Utah have a significant pocket gopher population.
Pocket gophers and moles are sometimes confused. Pocket gophers have large teeth (that constantly grow and must be worn down by digging and chewing activity) that they are able to close their lips behind to avoid ingesting dirt during burrowing. Moles have small teeth. Pocket gopher eyes are readily visible, moles have very small eyes that are difficult to see. Moles will leave disturbances along the surface of the ground; pocket gophers leave fan-shaped mounds from excavating their burrows and connecting tunnels. Of course, the name “pocket gopher” refers to the external fur lined pouch on both sides of the head that the animal stores small amounts of harvested plant material.
Whether you love, hate or are disinterested in our burrowing friends, there is ONE thing you can’t do if you have evidence of them in your yard, and that is to ignore them. Because they reproduce readily, and possess a strong appetite and storing habit, they will move farther and farther into a field or yardscape looking for food. Pocket gophers breed in the spring and summer and have a short gestation period of about 20 days, with litter size averaging less than a half dozen. They can’t be entirely eliminated; they CAN be controlled. Controls range from deterrence to extermination.
Let’s begin with deterrence. Flowerbeds and raised bed gardens should be planted with a small poultry wire liner about 12 inches deep. It you want extra insurance against tunneling, you can line the netting with landscape cloth as well. Electronic devices can be used as well called “gopher vibration stakes” that emit sounds that initially will attract the curious gopher, but will eventually repel them as the regular sounding of the stake will irritate them. If you live in a neighborhood, the range is usually just good enough to send them to, or keep them in your neighbor’s yard! A good “mouser” cat can be surprisingly effective. We’ve watched our cat and our neighbor’s cats be amazingly patient stalking a gopher, catching several a year. In rural areas, owls and hawks like them if the gopher comes out of its burrow to snack on some surface plant.
As for extermination, there are three effective methods that I’ve used. There are two others that I don’t use and that I don’t recommend for anyone – flooding the burrows and using car exhaust to attempt to gas them. The reason for avoiding these approaches is simple; you don’t know where the tunnel runs lead. You can flood areas you didn’t intend to, or send car exhaust where you can harm yourself or others. In addition, these methods have limited effectiveness as many times tunnels are plugged along the way due to the animal’s ongoing excavation activities.
Bait, traps and gas “bombs” are my go-to methods for gopher control. However, to use these effectively, you need to understand the basic method of tunneling that gophers do. Once you see the pattern, you have a very good chance of using one of these devices and getting the desired result. Of these three methods, only the trap will yield actual evidence that it did (or did not) work immediately. The effectiveness of the other two will evidence itself in reduced or no activity, or continued burrowing activity.
To make any of these methods work, you need to place them in the main channel. The fan-shaped soil mound with a soil plug in it is NOT the main channel. However, it tells you where it is! First, look at the mound and note that the fan of soil radiates away from the soil plug. You will find the main tunnel about 16 inches away from the base of the fan, about 12 inches down, and running at a right angle to the excavated soil. Why does the gopher do this? As the tunnels are being dug and excavated, a significant amount of soil builds up that the gopher needs to get out of the tunnel system. Every so often, it will dig into the side of the passageway, and start digging 90 degrees to the line of the tunnel, and then slowly arch up until it surfaces. It will then push out as much dirt as needed, then “close the door” with a soil plug to keep predators out.
Now that you know that the main channel is about 16 inches from the base of the mound, you can choose your method. If you are using bait, you will use a dispenser that has a sharp point on the bottom, and a bait hopper and dispenser on the top. Push the point into the soil along the likely location of the tunnel until you feel the soil “give” — you have now put the tip in the tunnel. Dispense the bait.
If you wish to use a trap, you will need to dig up the tunnel and expose to sides of the passage. The gopher will reveal what side of the channel it is on in short order, as it doesn’t like any part of the tunnel system open. If using a box-style trap, cut a clean face around the tunnel and put the trap up against it and seal the gap with soil. Be sure to leave the hole on the end open, as the gopher will usually come up to it to inspect it and be killed. If using inline traps that fit into the tunnel, be sure to tie a strong line or cable to them and fasten to a stake as caught gophers tend to drag the trap back down the tunnel before expiring.
As for the gas method, I use a product called “Giant Destroyer.” This is readily available from home centers and comes with four cartridges on a card. There are other brands available as well. For those of you that have experience with sizable fireworks such as M-80’s, they look similar to them, but larger. Of course, the “Giant Destroyer” product doesn’t explode! It does a make a thick white smoke that is toxic to the gopher. To make effective use of a gas cartridge, you will again need to locate the main tunnel and open an area that is large enough that you can see which end of the channel the gopher plugs. Once the gopher gives away its position, clear out the new soil and place it by the hole. Insert a fuse in the cartridge, light it, and place it as deeply in the tunnel as you can rapidly, and then pack the hole with soil to force the gas into the tunnel system. It’s advisable to leave everything as is for a few days to gauge if your efforts were successful. If so, cover up the hole, and if in a grassy area, place the dug-up grass patch back over the repair and water it in.
A word of warning: It’s possible to have “collateral damage” when using baits. If a gopher ingests it, and gets caught by a hawk, cat or even a dog before dying, you could poison them. I’ve not had problems with the gas from cartridges going where I didn’t want it to go, but I haven’t used this method near the house either. The cartridge puts out a limited amount as well. Traps are the only method that does give proof of elimination immediately, but a trapped and dead gopher can be unsettling to some. You decide which method meets your control needs the best.
UPCOMING GARDENER EVENTS
Learn how to prune fruit trees for productivity and tree health! Attend a Master Gardener public workshop by Wade Bitner, NEXT WEEK, on Wednesday, Feb. 26, from 7 p.m. to 8 p.m. at the USU Extension Offices at 151 N. Main, Tooele. With many years of experience in horticulture and apple orchards, Wade will take the mystery out of successful tree pruning by giving you systematic pruning steps for various back yard fruit trees, including apples, peaches, pears, apricots and cherries. There is no charge for this event.
Fruit Tree, Grape and Berry Pruning Demonstrations, Saturday, March 8! Learn “hands on” how to prune apple, cherry, peach, pear, grapes, raspberry and blackberries. Session One will be at my home at 984 Ironwood Road, Erda, from 10 a.m. to Noon. Session Two will be held at the Bitner home at 140 Durfee St. in Grantsville from 1-3 p.m. Dress Warm!
Spring Garden Expo, Saturday, March 1. Registration at 9:30 a.m. Event begins at 10 a.m. and goes until 2 p.m., $5 admission. Sessions include roses, turf, soil building, organic gardening, All American plant selections and self-watering containers. Main session at 1 p.m., Mike Pace, USU Box Elder County Extension Agent, “Fruit Trees in Your Back Yard.” Held at USU Extension Office, 151 N. Main, Tooele.
Jay Cooper can be contacted at firstname.lastname@example.org, or you can visit his website at dirtfarmerjay.com for insights on gardening, shop skills, culinary arts and landscaping.