Holes? Oh No -- Voles!!
Question: I know this has been covered on past shows, but what are your suggestions on identifying and driving off those burrowing critters, voles and moles? Thanks.
Question: Dear Mike: On a recent show you talked with a woman from NC about mole control using beneficial nematodes and milky spore disease. We live in
Question: Over the past few months my backyard has suddenly changed from a grassy square to a place where the earth is no longer level, with holes all over. I have 3 dogs and so never use chemicals outside. What could be doing this to my backyard and what can I do of a healthy nature to get rid of the problem? Thanks. You are my best resource.
Answer: Boy, Sheila's plaintive plea sure reminds me of when Princess Leia sent that message to Obi Wan, doesn't it? I'm comin' Sheil—just let me find those Daylily droids and my trusty Slug-Saber and I'll save you from that nasty Darth Diazanon!
All seriousness aside, our email has been absolutely burning up with similar complaints. Generally DEER win the '
Moles are mostly blind, strange looking little guys with BIG front claws that eat grubs and earthworms in lawns. They NEVER eat plants; but the raised tunnels can make your lawn look really bumpy.
Voles make lots of little holes in the ground; they look more like mice, but with really long weaseley snouts. Voles are a HUGE garden threat; they eat plants, and lots of 'em. Their favorite foods are tulip bulbs and the roots of plants like host as.
So, which do YOU have: Mole tunnels or vole holes?
If You're Troubled by tunnels on top of your turf…
The moles doing that digging are eating Japanese beetle and other grubs that ARE devouring your lawn's roots. The fastest way to wipe out those grubs is to release beneficial nematodes into your lawn when the temperature hits 55 degrees. These microscopic predators only harm pests—like the grubs of Japanese, June and Masked chafer beetles and flea larvae! A kitchen sponge-size package containing ten million nematodes costs around thirty bucks and treats 600 square feet of lawn. Water them in at dusk, and they'll rid your lawn of grubs within a few weeks. Then, with their food all gone, the moles should pack up and leave.
The organic supply company GardensAlive! is one of the premier sources for these helpful little microscopic wormies; they're on the web at www.gardensalive.com. For other suppliers, simply search the phrase "Beneficial nematodes".
For long-term control of Japanese beetle grubs, treat your lawn with "Milky Spore" disease. Yes, this naturally occurring organism, which has been used against Japanese beetle grubs for the past 50 years, IS a 'disease', but a disease that only affects the grubs of Japanese beetles and rose chafers. That's it. This control is SO specific it doesn't even harm other kinds of grubs, like those of June beetles. And it's totally safe for you, your family, pets and wildlife. Available at most garden centers, you apply teaspoon-sized amounts in a checkerboard pattern across your lawn and water it in.
It takes a few years for Milky Spore to become established in warmer regions, and it can take a fairly longtime—up to five years—in the Far North of the country. But once it does become established, no grubs will be able to survive in your lawn for the next 15 to 20 years, no matter how many eggs nasty female beetles lay in your turf.
Now, because it does take so long to establish, it won't do anything to control your grubs (or moles) the first year or so. That's why I recommend releasing nematodes to knockout your current grub population and applying milky spore for long-term future control. They won't affect each other—in fact, you could apply both on the same day.
Castor Oil May Work Against BOTH Underground Pests
Castor oil definitely sends moles scurrying to do their tunneling in the neighbor's lawn. And many gardeners report that it chases nasty voles as well! Most garden centers now carry ready-made castor oil repellant products in spray able and granular form. And here's a special note to our listeners with more exotic pest problems: The labels on some of these products say they're effective against armadillos and pocket gophers as well!
(If you can't find any such products in your local garden center, Gardens Alive! sells dry, spreadable castor oil under the name "Mole-Med")
Want to try mix in gup your own at home? Just add two tablespoons of castor oil to a sprinkling can filled with a gallon of warm water, add two drops of dish washing liquid, and sprinkle, stirring constantly, on the infested area.
Whether home-made or store bought, apply when the lawn and weather are dry. If heavy rains hit, repeat a day or two after they end; otherwise, reapply once a month until you see no new tunnels.
Holes? Oh no--VOLES!!!!
If you have lots of holes in your lawn, you have VOLES—fast-breeding plant-eating pests that are MUCH worse than grub and worm eating moles. Castor oil repellants—home made or store bought—may chase the pests over into your neighbor's lawn. So might the garlic based sprays that keep mosquitoes out of outdoor areas.
Sorry, but a British gardening magazine tested those battery-powered vibrating devices you stick in the ground, and found that they did not repel underground creatures.
Having outdoor cats on patrol DOES work; save a mouser from a shelter, give them a warm place to sleep and access to the garden, and they'll do endless good deeds for you. So will Jack Russell terriers and similar breeds of 'ratting' dogs. As will hawks and owls if you put a roost in the middle of the infested area. Nothing fancy—just across beam six to ten feet off the ground for them to hunt from.
You can also catch voles in mousetraps baited with peanut butter; place the traps underneath big plant leaves; voles don't like to come out in the open.
And you can protect a veggie garden from ANY burrowing creature with a fence sunk two feet into the ground. Because voles are SO small, however, you'll need to make it a small gauge fence to begin with, or, even better—a six footer of regular animal fencing whose bottom three feet are reinforced with hardware cloth—no miserable mammal can get through those small openings!
You Bet Your Garden ©2004 Mike McGrath