   Pocket Gophers and a New Control Method - December 13, 2000 Jeff Schalau, County Director, Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County It has been exactly two years since I've given attention to pocket gophers and just like the topics of my columns, they keep coming back. To effectively control them, one must learn their habits and become a dedicated observer. This article will cover identification, behavior, breeding, and a new experimental control measure for these varmints. Pocket gophers are probably the most common vertebrate garden pest encountered by Arizona gardeners and of the three species of pocket gophers found in Arizona, the Valley Pocket Gopher is most common. To be sure you are dealing with a pocket gopher, look for a round mound of loose soil that has a smaller plug of loose soil in the center or to one side within the main mound. If you don't see this characteristic mound, then you may have another pest such as a rock squirrel. Pocket gophers live their entire lives in the soil, leaving only to occasionally feed above ground, to travel to a new area, or to get around an obstacle. They usually are five to seven inches long (without the tail), have pale to dark brown fur, wide headed, have enlarged front feet (the better dig with), have long upper and lower front teeth (the better to eat roots with), and a short tail with tactile hairs to allow them to feel their way when traveling in reverse. Pocket gophers are named for the fur-lined pouches outside of the mouth, one on each side of the face. These pockets are capable of being turned inside out and used for carrying food and moving soil. Pocket gophers have one or two litters per year. These consist of between one and ten (usually three or four) offspring per litter. Their burrows are between 4-18 inched deep, may be linear or branched, and usually have deeper side branches that serve as nests or food caches. The previously described characteristic mounds are at the ends of tunnel branches and each gopher can push up one to three mounds per day. The mounds give an indication of areas with the greatest feeding or nesting activity. Feeding occurs in three ways: 1) feeding on roots they encounter while digging; 2) surface feeding a body length or so from their tunnel opening; and 3) pulling vegetation into the tunnel from below. These strict vegetarians may feed on herbs, grasses, bulbs, shrubs, and trees. Alfalfa and dandelions are preferred foods, although other tap-rooted weeds can attract gophers. Pocket gophers may be controlled with varying success by trapping, gassing, poisoning, flooding, cultural methods, use of repellents, and exclusion. I have always had the greatest success using lethal traps such as the Macabee wire trap (I was a landscape maintenance guy for several years in my distant past). This year, I have been experimenting with a new gopher control device that was shown to me by Cottonwood Master Gardener Vic Heinz. This device is easy to build and works well. It consists of a five gallon plastic bucket, a flush mounted "pancake" fan, and a supply of highway flares (the kind put out on the road to warn other drivers of danger). Five gallon plastic buckets are readily available from food establishments and hardware stores and highway flares (Fusees) are available from auto parts stores. The fan can be purchased new from the local electronics store or recycled from your favorite salvage yard. Buy a three or four inch fan. Before purchasing a used fan, read the label to determine whether it is 12V DC (for automobiles and solar) or 120V AC (household current) and make sure it works. To build the device, place the plastic bucket upside down on the ground, place the fan on the center of the bottom of the bucket, and trace the outline, the screw holes, and the circular opening of the fan onto the bucket. Cut only the circular hole where the air passes through and drill holes to attach the fan. Use some small machine screws to attach the fan to the bucket making sure the air blows into the bucket when the power is on. Most of you should be getting the idea now: a major gopher tunnel is exposed, the device blows the fumes from the ignited highway flare into the gopher's burrow and, if all goes as planned, the gopher is asphyxiated. The smoke and fumes of the flares are heavier than air. You should see small plumes of smoke rising from nearby tunnels and air vents wafting around after the device is deployed. For effect, you may want to stand on the nearest hilltop and play "Taps" on your kazoo. Here are some notes from my experiences. It is easier to find the tunnel network where recent activity has taken place (near fresh mounds). Seal the ground at the base of the bucket after igniting the flare to ensure that the smoke is not escaping the tunnel. Keep clear of the area to avoid breathing this smoke. Clear dried vegetation from the burrow area and have a source of water nearby in case a fire is started. Like any new activity, using this device effectively requires practice. The "Heinz Gopher Trap" has worked well in my yard where gophers were dining on roots of newly planted fruit trees. This device is just another tool to add to your arsenal. Finally, watch the classic movie ACaddyshack" for inspiration. Don't forget, there are many other effective strategies for controlling gophers. The University of Arizona Cooperative Extension has publications and information on vertebrate pest control. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 or E-mail us at mgardener@kachina.net and be sure to include your address and phone number. |