Saturday, December 26, 2009
Fish Oil Emulsion May Make Gophers Move Out
By Richard Fagerlund
For the Journal
Q: We have small children and a cat, but we also have a gopher problem in our backyard. They've been digging up the new lawn we had put in. Is there a safe way to get rid of them? — C.M., Corrales
A: Pocket gophers construct burrows under the ground using their strong forelegs, enlarged claws and even their teeth. Their vision is poor because of their habitat. Their hearing is poor, too. When the gopher digs, it kicks the dirt behind it with its hind feet. When a lot of loose dirt has accumulated, it turns around and pushes the dirt to the surface using its forepaws and face. The resulting mounds are an indication of their presence in your yard.
Gophers feed on the underground portions of plants, but will occasionally come to the surface and pull green vegetation underground. They live alone in their tunnel system, but males will enter female tunnels during mating season, usually early in the year. Female gophers will have one to seven young at a time. The baby gophers will disperse on the ground when they are mature enough to leave their mother and often fall victim to predators at this time. They usually have only one litter per year.
Actually they are very beneficial animals. A single gopher can move about a ton of soil to the surface every year. Their tunnels are constructed and then fill up with dirt as they are abandoned. The old tunnels contain the nests, waste material and partially filled pantries well below the surface where they become important as fertilizer.
Soil that has been compacted by cattle trampling, grazing and machinery is benefited by the tunneling process of gophers. In the mountains, snow and rainfall are temporarily held in gopher burrows instead of running across the surface, causing soil erosion. The mounds the gophers make also bury vegetation deeper, thus increasing soil quality over time. Additionally, fresh soil in the mounds provides a fresh seeding area for new plants, which may increase the variety of plants on a site. Gophers are also in the food chain and are fed upon by large birds, other mammals and snakes. Other animals such as lizards and toads take refuge in the cool, moist burrows.
As much as I am trying to make the case that gophers have a place in our area, there are times when we have to control them. Poisons are available, but I never recommend them. Most of the gopher baits contain strychnine, diphacinone, chlorophacinone or zinc phosphide. None of these rodenticides are very pleasant and accidents can result with other animals digging them up.
There are traps available that can be placed in the burrows, but they are not easy to use and have only limited success. I have found that the best method of gopher control is simply asking them to move. You can do this by pouring a foul smelling liquid into their tunnel system. Fish oil emulsion works and I have been told that castor oil is also effective. Since gophers generally live alone, once they move, they are not likely to return unless they are forced to move again, so a repellent can be very effective.
When using a repellent, you will have to probe the dirt to find their tunnels. Generally a tunnel will run straight between two mounds and they are normally about 18 inches below the surface. You can use a metal rod or even a pool cue to probe the dirt. Once you hit the tunnel, the probe will fall through. Then take a long-stem funnel such as used to put oil in cars and place it in the hole created by the probe. Pour the repellent into the funnel and move on to the next tunnel.
Q: Since the administrator of the Environmental Protection Agency just announced that the agency would be controlling greenhouse gases, will this have an effect on the usage of sulfuryl fluoride (Vikane) in fumigations? — D.L. Albuquerque
A: Absolutely. Researchers calculated that one kilogram of sulfuryl fluoride emitted into the atmosphere has a global warming potential approximately 4,800 times greater than one kilogram of carbon dioxide. That is pretty impressive.
Go to http://scrippsnews.ucsd.edu/Releases/?releaseID=965 for information. The chemical's annual use in California creates emissions equivalent to the carbon dioxide produced by 1 million cars and California accounts for 60 percent of the sulfuryl fluoride used in the world.
We don't use anywhere near that amount in New Mexico, but it is registered for use here and has been used occasionally when drywood termites are found in a home. I believe with a record like this, sulfuryl fluoride won't be around much longer.
Richard "Bugman" Fagerlund, an entomologist, owns and operates "Ask the Bugman" Common Sense Pest Management. He can be reached by phone at 385-2820 or by e-mail at firstname.lastname@example.org. His Web site is www.askthebugman.com.