Eliminating Gophers From
Crescent-shaped mounds are tell-tale signs when Pocket gophers are present. Gopher mounds are the end result of digging tunnels. Gophers dig tunnels with their front claws (which grow 3.5" per year) and teeth (which grow up to 14" per year) while kicking the loose soil back with their hind feet. When enough soil has been moved, the gopher will somersault in the tunnel and push the soil out with his head and front feet. This excess soil is pushed out the lateral and piles above ground crescent shaped from the direction of the tunnel. (Photo: "typical crescent shape" - click on photo for larger image).
Nesting burrows may be several
feet deep but gophers spend the majority of time in tunnels which are
generally 4 to 12 inches below the surface. During mating season in
spring, gophers will travel above ground seeking mates. About nine or
ten weeks after mating the young are weaned and travel above ground
to establish new burrows. Gophers are opportunistic, and will take over
a burrow system if the previous resident leaves. They are active year
around, 24 hours a day alternating work with periods of rest. Active
open tunnels are easiest to find in the early morning, and are usually
plugged for the better part of the day. Mounds are not pushed up at
all openings, sometimes only enough soil is used to plug the hole.
Trapping gophers can be time consuming, somewhat disruptive and labor intensive. That being said, it's the most effective way for the homeowner to eliminate one or two gophers from small garden areas. RoseCare.com sells the two most popular types of traps, wire traps (Macabee, Victor) and box traps (Blackhole). Both of these traps are baitless and if set properly, will kill gophers returning to seal their run.
There are many "secrets" to successfully eliminating gophers. This tip sheet outlines some of the secrets that have been successful for us.
Where to set traps
The best place to set traps are in active fresh mounds which are obvious when there are only one or two. When trapping in areas where there are many mounds, look for those with moist diggings. If there isn't an obvious choice, rake out all the mounds and return the next day to see which reappear. Although both types of traps can be set in lateral runs (the single run that comes to the surface), more reliable results can be achieved by exposing the main run and setting two traps, one facing in each direction.
How to set the traps
Before exposing the run or setting traps, wear gloves and rub the traps and your trowel in the soil to remove your scent. Wary gophers are difficult to trap. We've seen many a trap neutralized by gophers who simply push soil into them. If this is your first attempt at trapping, we suggest you try box traps. They are the easiest to set, monitor, and to remove the dead animal from.
Box traps must be set flush against the exposed tunnel. When trapping in the main run both types of traps should be set on a level surface. Wire traps need to be set inside the tunnel, tied through the spring coil, and staked down for easy retrieval. Once the traps are set and placed, the holes leading to the traps should be covered with enough vegetation to prevent any light from entering the tunnel. Air flowing through the vegetation signals the gopher to come up and plug the opening. Although both types of traps are baitless, some suggest box traps can be baited by plugging the vent hole with a carrot.
How to expose the tunnel
Analyze the shape of the mound. When gophers push excess soil out of their run, it creates a crescent shape in the direction of the lateral. Begin your search for the main tunnel on the inside of the crescent. Whether the crescent is visible or not, use a hand trowel or small round point shovel and push it straight down, carefully lift the soil straight up and set it aside. If you don't find the tunnel with the first attempt, rotate your digging tool to 5 or 7 o'clock and repeat the process until the tunnel is found. This rotation should create a circular hole. If you push your spade in diagonally, it's very easy to compact loose soil back into the main run making the tunnel very difficult to find. Once you've opened the main run, if possible expose and additional 6" to a foot in both directions before placing the traps.
Of the three most common methods of controlling gophers (traps, bait, and fumigants), fumigants are considered the least reliable. In areas of the garden you don't want to disturb, or if you see a gopher actually working, fumigants can be effective and convenient. In order for fumigants to work, the gopher must come in contact with the gas, ideally in moist well sealed soil. Where burrow systems are extensive or if the soil is dry or sandy, gas may seep out before reaching the gopher. For this reason we usually recommend fumigation in combination with baiting. Baiting has a much longer residual. In combination, gopher control can still be achieved if the fumigant created a sub lethal dose or has long since gone. Our homeowner fumigants are sold in the form of gas cartridges (Gopher Gassers & Giant Destroyers). These fuse lit cartridges are placed in the open tunnel fuse end first. Before lighting the fuse, have soil ready to plug the opening to prevent gas leakage.
The most efficient way to control gophers in large areas is to apply baits. This procedure can be done with a trowel, screwdriver, or by using professional baiting tools available through us like the Gofer-Dozer or the Elston Gopher Getter Jr. Either way the objective is to place the bait inside the gopher run. One method of placing bait is to use a trowel or shovel exposing the tunnel at the mound, placing the bait inside with a long spoon and backfilling taking care not to cover the bait. Another method is to probe for the tunnel about 6" away from the mound and deposit the bait with a funnel or gopher probe. To locate the tunnel, probe 6" to a foot on the inside of the crescent. Whether you're using a long screwdriver or commercial probe, when you find the tunnel, the probing device will suddenly move with little resistance to the tunnel floor. Using a gopher probe, pull back 1/2 inch and the bait is trigger dropped to the tunnel floor. If you are using a screwdriver or other home device to locate the run it must be removed so a funnel can be inserted to pour a pre-measured dose of bait into the run. Probing for gopher tunnels is very fast, but can also be a little tricky. There is a certain "touch" involved, but with practice, anybody can be successful locating tunnels with gopher probing tools. Baiting with probes is easiest in moist conditions, or in loam soils. If your soil is too dry it can be difficult to push the probe through the soil. If your soil is too sandy, it tends to fall on and cover the bait as the device is withdrawn.
Repellents / Exclusion
Wind machines, vibrating and ultrasonic devices have all been invented, tested, and marketed to repel gophers. At this time we haven't read any objective independent studies that suggest these devices work.
Gopher baskets are prefabricated cylinders of wire netting designed specifically for protecting young trees and new plantings in gopher infested areas. RoseCare.com sells Root Guard Gopher Wire Baskets in three sizes to accommodate 1, 5 and 15 gallon trees and shrubs. These baskets are an excellent method of exclusion, but should not be relied upon as the sole source of protection for your valuable landscape plants.