Banishing Animals from your Garden
By Jonathan A. Leonard
How do you deal with Peter Rabbit, Charlie Chuck, and Sammy Squirrel? Do they cruise your vegetable garden at will? Are you tired of putting up with this, and equally tired of half-measures that don't work?
If so you're not alone, because most countermeasures work poorly. We have years of experience controlling deer and small animals. At other sites we offer many tools-barrier fences, electric fences, traps, chemical repellants, untrasound blasters, infra-red detectors, noisemakers, and water sprayers directed at removing or repelling animals of various sorts. But few of these measures effectively focus their attention on the small problem of protecting home vegetable gardens. Maybe that's why nearly all have major weaknesses-being too costly or time-consuming or passive or impractical in a vegetable garden setting to do this particular job well.
Mr. McGregor's Fence® is designed specifically to protect home vegetable gardens. It works by combining a low fence with a mildly charged wire. Small animals pause to explore the fence, encounter the charged wire, and lose their yen for lettuce. Because the wire startles and repels the invader, the barrier fence doesn't need to be tall, massive, or buried-and it isn't. That makes the whole system affordable and easy to erect. But the low fence is enough of an obstacle so that the gardener doesn't have to worry about invaders failing to encounter the charged wire and getting through, or about people (including gardeners) failing to see the all but invisible charged wire and tripping over it.
Of course, this sounds fine in theory, but how do we know that Mr. McGregor's Fence® really works? For one thing, we have more than 15 years of experience in an area overrun with woodchucks, rabbits, squirrels, and raccoons. In the early years, we began with a tall (36 inch) barrier, but soon discovered that this height wasn't needed and that a barrier only 18 inches high worked just as well. What's more, it was definitely working, as your author affirmed one time when he unplugged the fence charger to remove encroaching weeds, forgot to reconnect it, and found that most of his vegetables disappeared.
Besides such test garden experience, there are good logical reasons for supposing that the barrier fence can be low. Electric fence systems designed to control pets typically deploy low wires. Our fence never shows the ravages of attempted burrowing or gnawing, indicating that concerted assaults of this kind are very rare. And while woodchucks are good at climbing over fences, our fence's excellent record of success suggests that efforts to surmount the barrier and charged wire this way are also rare.
Repelling Squirrels
Beyond that, our faith in the low barrier principle has been bolstered by our experience with squirrels. The earliest version of Mr. McGregor's Fence® wouldn't keep out squirrels very well, because they could get through the barrier fence's 2 inch x 3 inch openings without touching the single charged wire. But most vegetable gardens are in sunny spots with no low overhanging tree limbs, and squirrels typically enter them from the ground. Also, nut-loving squirrels aren't really intent on eating vegetables-they just take a test bite here and there; so their drive to get into vegetable gardens is less compelling than that of the more veggie-oriented chucks and rabbits.
All this suggested that a properly modified Mr. McGregor's Fence® could repel squirrels. So we developed a squirrel barrier (see Catalog) that in effect miniaturized the system. First we added a supplemental small-mesh plastic fence only 9 inches high that we tied to the lower half of the barrier fence-to make squirrels stop at the barrier. Then we added a second charged wire below the first at a height of 4 inches-the right height to keep squirrels from burrowing.
These additions did the trick. In testing this system repeatedly we didn't use take-it-or-leave-it vegetables; we used squirrels' first love-unshelled peanuts. We found that pounds of peanuts scattered outside the test plot vanished in an hour or so, while those inside remained untouched. Unable to evade the charged wires despite numerous efforts, the squirrels decided to leave the fence alone. Eventually, over the course of a week or so, the squirrel-proof peanuts inside the fence dwindled and vanished-not because of squirrels but because birds got them. (Some of our other web sites, including www.gardenpest-x.com, sell netting to keep out birds.) Fence Advantages
Besides demonstrating the effectiveness of our low barriers, this experience shows why Mr. McGregor's FenceŽ is Nature-friendly. That's because it doesn't harm or even displace the target critters. All it does is train them to drop the vegetable garden from their foraging itinerary. For some years now I have had a woodchuck living about 20 feet away from my personal vegetable plot. He never seems to probe the defenses, having apparently decided that Mr. McGregor's Fence® won't bother him so long as he doesn't bother it. And of course he's right about that.
Beyond this, Mr. McGregor's FenceŽ has several other advantages. Because the system needs no megabarrier, it saves both money and effort. In fact the whole system-barrier fence, electric wire, fence charger, and connectors-costs less than half what a good barrier fence would cost and takes about a third the time to install.
Also, it needs no gate. It's so low that the gardener simply steps over it. That's a blessing, because garden gates take time to build, are prone to penetration by small animals, and won't keep out anything if one forgets to close them. Of course, there may be occasions when one wants to admit a tiller or other heavy equipment to the garden. But in such cases a few minutes of work will serve to detach the barrier fence and electrified wire at the point where they come full circle, thereby making an ample temporary opening.
The system is also durable. Given normal use, the fence charger, insulated connecting wire, and aluminum charged wire in our kits should last for many years. The fencing (made of plastic-coated steel wire) will last at least a decade. And the fiberglass posts are rated to last for 30 years. Thus, Mr. McGregor's FenceŽ can be expected to outlast most barrier fences as well as many of the vegetable gardens it protects.
Electric Fences
So what about the traditional problems of electric fences? How does Mr. McGregor's FenceŽ cope with them? For starters, the fence energizers it uses weren't designed to restrain cattle but merely to control pets. So barring extraordinary abuses such as by-passing the fence energizer altogether, the system is safe for both small animals and people.
What's more, unless one happens to be holding onto the charged wire in a thunderstorm, the system is lightning-proof. Lightning has been a big problem for electric fences in the past-because they can act like lightning rods. And since traditional fence chargers didn't block the house current flowing through them, the fences that they served needed to be securely grounded-by a solid metal ground rod maybe a half-inch in diameter and six to eight feet long. Otherwise, lightning striking the exposed fence wire could surge back through the fence charger into the gardener's house and wreak havoc.
The AC-powered fence charger that we use is different. It uses no ground rod. Instead it builds up a static charge on the exposed wire. That charge is sizeable; but a person or animal touching the wire only gets a little "zap." That's because the fence charger blocks immediate restoration of the charge, so the toucher only gets exposed to the electrons that happen to be in the wire when it is touched. Similarly, if lightning strikes the wire, the fence charger blocks the momentary lightning surge, preventing that surge from joining the regular house current and so protecting the gardener's house.That helps to explain why this particular charger is Underwriters' Laboratories approved and why it is so safe.
The principal drawback of Mr. McGregor's FenceŽ involves neither effectiveness, cost, permanence, nor safety. It involves maintenance. If vegetation encroaches on the fence and reaches the charged wire it can discharge the wire and neutralize the system. For this reason our fence kits come with a three-foot weed barrier of polyethylene film. Even so, the gardener will need to clear away tall weeds (ones that lean over the strip of mulch -covered polyethylene) and fast-growing vines about every two weeks during the growing season.
That's no problem for the regular gardener who expects to tend the garden every week or so-because this job takes little time. But it can pose problems for gardeners who must sometimes be away from their gardens for extended periods. Such gardeners will find it worthwhile to put down three-foot strips of weed barrier inside and outside the one provided in our kit. Indeed, gardeners who anticipate lengthy absences from their vegetable gardens are well advised to cover all of the garden with this or similar stuff and to plant their vegetables through it-not just to keep Mr. McGregor's FenceŽ working but also to keep weeds from running riot while they're gone.
Dealing with the Right Critters
While we're discussing pros and cons, we should mention one more advantage of Mr. McGregor's Fence®. That is, it specifically targets those small animals (woodchucks, rabbits, and squirrels) that do most of the damage to home vegetable gardens. In addition, it also works against raccoons, deer, skunks and opossums. As yet we have no evidence that our fence works against armadillos, and it assuredly won't work against moles, voles, and pocket gophers; but armadillos are mostly scavengers and insect eaters, while pocket gophers live mostly underground and generally do far more damage to lawns, golf courses, and commercial farms than they do to vegetable patches. (For effective ways of dealing with armadillos, moles, voles, and pocket gophers, visit our web site at www.gardenpest-x.com.)
Guns, Baits, and Traps
Once we leave fences behind, we find that nearly all other animal control methods are general ones not directed specifically at protecting vegetable gardens. Even so, some of these methods can be helpful, and each has its own pros and cons; so it's worth glancing at each from the gardener's standpoint.
Most of the lethal methods involve risks or drawbacks out of scale with the vegetable gardener's difficulty. Guns are dangerous, their use is often barred by the proximity of nearby dwellings, they're typically brought out only after some damage has been done, and they only work when someone is attached to them. Poison baits can do in pets. And smoke bombs (used mostly against woodchucks) are problematic-especially if the unwanted browser's burrow is on your neighbor's land because soon after the offending animal is rubbed out another may move into its territory-often right into the victim's bombed-out burrow.
Many home gardeners object to such methods. They like bunnies and squirrels. They even have a soft spot for the portly woodchuck. What's more, they certainly didn't get into gardening for the money. Many did it because getting out in the yard and growing plants made them feel close to Nature. And of course, killing Nature's creatures runs contrary to that. So for reasons that go beyond the risks and drawbacks, many gardeners want nothing to do with lethal methods.
If we turn to non-lethal methods, we find that "kind" traps have a lot to offer. These are typically long, boxy affairs made of strong steel mesh and open at both ends. An unwitting animal, enticed by bait, enters the box, springs the trap, and finds itself in jail. If such traps are designed for the right animal (they come in various styles and sizes) and are properly placed, baited, inspected, and periodically rebaited, they may be just the ticket for removing a raccoon from the attic, an armadillo from under the shed, or a woodchuck from the garden.
But the trapper needs to be sure there is really only one or at most a few animals to be removed, and that no others will move into the trapped animal's vacant territory. That's especially likely with woodchucks (which love nothing better than a vacated burrow), rabbits (which multiply, well....like rabbits), and squirrels (which congregate at food sources).
Some decades back, when I was in my twenties and knew little of bird feeders, I got a feeder that was not squirrel-proof, installed it on the edge of a squirrely woods, and soon found about a dozen happy squirrels under it. I thereupon resolved to capture these mischievous interlopers and I did. I trapped and exported 15 squirrels, at which point the count under the bird feeder was 21. Obviously, an ocean of squirrels lived in the adjacent woods, and I was trying to empty the sea with a bucket.
Another drawback for the vegetable gardener is that by the time the trap is dragged out a good deal of damage has commonly been done-and more may happen before the offending animal is caught. Also, from the animal's standpoint being deported to new territory may not really be humane. Raccoons commonly kill stranger coons released into their territory; woodchucks may have trouble establishing a new territory on rivals' coveted feeding grounds; bunnies plucked from their supportive family groups are handicapped; and even squirrels must find new refuges and food sources in a strange land filled with unknown perils.
Clearly, box traps can help the vegetable gardener in mid-season if the garden's primary defense system has failed. But their humaneness is open to question; and they do not work well as primary or sole defenses, especially where adjacent land harbors reinforcements. Chemical Repellants
Chemical repellants-everything from mothballs to an item imaginatively dubbed "Not Tonight Deer" likewise have their uses. They can discourage deer. They can keep other invaders out of lawns and flower beds where fencing is not the answer and wild creatures may have less incentive to intrude. And they can work very well indoors, where odors may get strong enough in confined spaces to expel the most tenacious pests.
Many years ago in the late fall my parents had a problem. Their summer home was invaded by a raccoon that came to live between the walls, occasionally showing up in a back workshop or my father's office. My parents didn't want to kill the animal, partly because the smell would be ungodly if it died in the wrong place; and they weren't going to be in the house long enough that season to trap it. So they called the humane society and asked what they should do. The answer they received was "moth balls." Acting on this advice, they put moth balls in the two coon-infested rooms and up the broken chimney that the coon used as an entrance-and lo and behold the creature soon decamped.
Such dramatic indoor success stories contrast sharply with chemical repellants' poor reputation when it comes to protecting outdoor vegetable gardens. That's partly because these repellants have trouble with the weather. Rain washes them away; wind dispels them; and even those held in special receptacles must waft out into the moving air to do their job. Hence, even those that don't give vegetables a bad taste need to be periodically replaced.
Worse, just which repellant to use and how often to replace it is hard to tell. Vegetables grow fast, and new untreated growth may be eaten. Different species have different sensitivities to different odors. Some animals may get habituated-even to predator scents if no predator shows up. Your own nose may or may not register when the repellant has ceased to work. An animal with no great incentive to raid your garden may back off, while one that is hungry and hyped up-really intent on veggies-may ignore the scent barrier. For all these reasons, the record of scents as vegetable garden protectors is erratic and disappointing.
High-tech Gadgets
The last major class of pest control devices is "high-tech" gadgets. These include ultrasound generators, infra-red detectors, water sprayers, and noisemakers with success rates that depend on how they are applied.
Let's start with ultrasound. Though we don't hear it (it's beyond our audible range), it isn't ultrasonic to the target animals. It's ordinary sound to them. So it's not especially mysterious, and they respond to it very much as we respond to startling, loud, or annoying sounds.
Among other things we find sounds much more powerful indoors than outdoors, because sounds reflect and reverberate indoors instead of spreading out. A traditional Scottish bagpiper is enjoyable on a large greensward but deafening in a closed room. This probably helps to explain why ultrasound repellants, like their chemical cousins, tend to work best indoors.
Also, our willingness to abide noise depends on our motivation. If adults should run into the full-throated sound of a rock band in a small space, most would be repelled by its volume-because they don't identify with its age-specific message-while many teenagers would actually be attracted. In a similar fashion, deer that are just meandering about may be put off by ultrasound, while animals with a purpose (like eating vegetables) are not.
Beyond that, while noise near our homes may bother us, it rarely causes us to pick up stakes and move out. Similarly, one does not commonly find that ultrasound devices cause rabbits and woodchucks to abandon their homes. And of course, both people and animals continually exposed to unusual noises tend to adapt. Indeed, they soon come to ignore the noises (unless they are associated with some threat) and even to lose awareness of them, because their minds learn to screen them out. This may explain why ultrasound tends to work better on animals with large territories (like deer) than on ones with small territories (like woodchucks and rabbits), because the latter are more likely to become habituated to the sound and ignore it. It also suggests why these devices tend to achieve their best effects early, soon after installation, before those temporarily repelled have had a chance to adapt.
To make ultrasound gadgets more effective, some of them have been combined with infra-red detectors-so that they go off only sporadically (when they detect a nearby animal or person) rather than all the time, thereby surprising their targets more and habituating them less. But this is only a temporary fix. People living near train tracks soon learn to ignore the hooting, rumbling trains even if the number of daily runs is small. The same presumably applies to animals. This goes a long way toward explaining why the makers of ultrasound products only rarely mention woodchucks or rabbits, and why such devices' general ability to protect vegetable gardens from determined trespassers is poor.
But noisemakers don't have to be ultrasonic and some aren't. One interesting and useful type sports a gaudy black and yellow crow's face and uses an infra-red sensor to detect encroaching animals, which it then startles with a burst of noise and water. This wonderful toy seems best suited to protecting flat things like lawns and low flower gardens, because tall plants or structures can block both its infra-red detector and its spray. Nor is it really suited to protecting well-traveled paths, because it detects people as well as animals and will startle and spray them with abandon. The device must also be maintained (it works off batteries, and like all water-sprayers it can get blocked or tangled up in weeds); and it needs a continually dedicated hose line under pressure-which must be switched off anytime the gardener wants to enter its domain. Beyond that, there is good reason to suppose that animals will become accustomed to this gadget very much as they become accustomed to ultrasound generators, and like the gardener will learn the precise range and coverage of its spray. All this suggests that this device does best protecting little-used sectors of the yard or even executing minor pranks (scaring and spraying one's friends and neighbors); and while it is certainly useful (especially against deer and troublesome dogs and cats), this noisemaker seems unlikely to give the average vegetable gardener much help.
Conclusions
As we have noted, vegetable gardeners trying to cope with the Peter Rabbit problem face restrictions. In general, they must deal with the problem in or around the garden because they don't control large expanses of surrounding territory. They tend to find lethal methods dangerous, ineffective, or objectionable. And they are confronting woodchucks, raccoons, and rabbits that have a real penchant for vegetables, live fairly near the garden, and commonly have a horde of relatives eager to replace them. Together, these special circumstances account for why our broad array of general animal control methods don't protect vegetable gardens very well.
In contrast, Mr. McGregor's FenceŽ directs its full attention to vegetable gardens. So it won't work indoors, and won't capably defend lush outward-leaning flower gardens where the very plants it is supposed to be protecting will neutralize it. But it does a fine job protecting home vegetable gardens-better than the original farmer McGregor did in the Tale of Peter Rabbit and notably better than other methods available today.
FURTHER READING
Adler, Bill. Outwitting Deer. Lyons Press, 1999.
Adler, Bill. Outwitting Critters: A Surefire Manual for Confronting Devious Animals and Winning. Lyons Press, 1997
Anton, Charles. Break-through Device Creates a Wall of Silent Noise that Drives Away Annoying Animal Pests. (Advertisement, Yard Guard sound wave device.) Christian Science Monitor. August 20, 1996; vol. 88, no. 186, p. 5, col. 1.
Chicago. Where the Wild Things Are. May 1990, vol. 39, no. 5, p. 136(8).
Hadidian, John (ed.), et al. Wild Neighbors: The Humane Approach to Living with Wildlife. Fulcrum, 1997.
Harrison, George H, and Kit Harrison (ed.). Squirrel Wars: Backyard Wildlife Battles and How to Win Them. Willow Creek Press, 2000.
Hart, Rhonda Massingham. Deer Proofing Your Yard and Garden. Storey Books, 1997.
Hart, Rhonda Massingham. Squirrel
