Controlling Rodents Naturally

Controlling Rodents Naturally - Garden Pest Tip

Control the mole

There are hills and canyons in and around Los Angeles where gophers are such an enormous problem that gardening is virtually impossible. In parts of Santa Clarita and the Antelope Valley, the only way to plant is to sink a fine mesh fence, to a two foot depth, around your garden. If you want to plant a small tree, a similar fence around the drip line or canopy diameter is needed to prevent gophers from chewing the tree's roots and, in some cases, from gnawing through its trunk.

None of the conventional gopher control techniques have been embraced by the general public. Trapping definitely works, but it is accompanied by the never pleasant task of extracting the dead animal from the trap's skewers that pierce it on both sides. You might choose to dispose of the trap (a $6 item) along with the dead gopher, but this will only mean purchasing another trap later on when other gophers reclaim the area, which they always do. Smoldering sulfur sticks, inserted into gopher burrows, are sometimes effective at asphyxiating gophers; with this method, you don't have to worry about retrieving the dead animal. However, unlike with traps, there is no certainty that the sulfur sticks have worked. Oats laced with strychnine are the most popular poison bait, except that lots of people don't like handling noxious chemicals and, again, you can never be sure if the gopher got away.

Household pets, especially cats, have been known to afford some measure of gopher control, and there is anecdotal evidence that poisonous bulbs, such as daffodils, will not be eaten by gophers, suggesting that a garden surrounded by such bulbs will be gopher free. Euphorbia lathyris (gopher purge) — sold in the herb and succulent sections of many nurseries — is promoted as a gopher antidote without justification; although gophers may not actually eat Euphorbia roots, the animals will burrow right through them to chew on roots of adjacent plants. Ultimately, neither pets nor poisonous plants are reliable deterrents to gophers.

As in so many other areas of life, the solution to our gopher problem may, in the end, come from above. In the specific case of the gopher, the solution may actually swoop down from above. The solution to the gopher problem, as recent research demonstrates, may ultimately prove to be a bird that is found throughout the world, a bird that consumes not only gophers, but, moles, voles, mice, and rats as well. This bird is none other than the common barn owl, a bird no bigger than a crow, with an unmistakable heart-shaped, chalky white, phantom-of-the-opera mask.

The fact that barn owls eat gophers is hardly news. In fact, biologists have long been privy to the knowledge that March and April are the peak breeding months of both owls and gophers. What this means is that there will be plenty of prey for the owls just at the moment when they are hungriest and also have fledglings to feed. This understanding has led to the reasonable assumption that if you could bring a pair of breeding barn owls into a gopher-infested area, the owls would happily take up residence and rid you of your gopher problem. But this assumption was wrong.

The breakthrough in owl-gopher research was reached when it was discovered that although barn owls are found throughout the world (excepting the higher latitudes), they will only come to an area by their own choosing. When you forcibly place them in a particular spot, they fly away. However, if you can build a proper nesting house for them, they will appear out of the clear blue sky and become your tenants. This is especially true in California and the Southwest, where the population of barn owls is prodigious.

To build an owl house, sink a 4 x 4 inch pole four feet into the ground and build a nesting box, to be attached at the top of the pole — which should extend to a height of 12 feet above ground level. The nesting box should be 16-24 inches on each side, with landing dowels, an entry hole 6 inches in diameter in front, several 5/8 inch drainage holes at the bottom together with a clean out panel, and four 3/4 inch air holes on the side. If placed in the sun, as opposed to under a tree, a slanted roof should be provided on the top of the box, extending several inches over the front and back to give the owls shade. Care should be taken not to place the nesting box in an area of intense vehicle or foot traffic since owls will not visit such noisy sites. Although barn owls reside wherever people do, they need peace and quiet during daylight hours, which is their nap time. Detailed instructions for building an owl nesting box may be found on the following web page: or call 209-369-8578 to order a brochure on the subject.

Intense barn owl research is currently being conducted at Kibbutz Sde Eliahu in the lower Galilee. The kibbutz grows all of its crops organically and is using owls for biological control of voles — rodents that are related to, and about half as big as, gophers.

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