Four-legged damaging pests

Photo courtesy of www.Morguefiles.Com.
A fenced-out deer is a good thing.

Ground animals, from deer to raccoons, can be just as destructive as hailstorms and insects. Experts estimate that wildlife crop damage costs U.S. farmers more than $4 billion annually, and that the majority of agricultural operations cope with some level of destruction. Many pests aren’t easy to discourage, but there are steps you can take to control them.

Reclaiming the crops

The first step is determining what types of animals are invading your fields. Once you identify the culprits, you can begin to battle them. The choices for control are varied with differing success levels, costs and labor requirements, according to Cornell University scientists. Methods also vary depending upon the types of animals involved.

Deer are a common enemy, with populations exploding in recent years. They live along the borders between wooded and cleared lands, so removing brush and high grass near fields may send them on a search for a new home.

If deer damage is light and limited to small areas, repellents such as Hinder (for carrots only) and Deer-Off may be worth a try. If damage is great or the population is large, those products may not be cost-effective. Keep in mind that repellents won’t offer complete protection and must be sprayed in dry conditions when an attack is anticipated.

Photo by Dave Menke, U.S. Fish and Wildlife Service.
Corn and watermelon are favorites of the nocturnal raccoon.

Deer populations can also be controlled by removing does of reproductive age, whether through selective hunting, if permitted, or relocation.

Most growers who have struggled with deer agree that the best solution is fencing. Although costly, fencing seems to be the one foolproof method for permanently ending deer damage. The gold standard is high-tensile, woven-wire fencing of 8 to 10 feet. If electricity is added, the height can be dropped by several feet. Although deer can typically jump 6 feet in the air, one encounter with a hot fence appears to quench that behavior. A Rutgers University study indicates that portable electric fencing is another option for deer and other ground animal control.

How much wood could a woodchuck chuck?

If woodchucks have invaded your farm, fencing and elimination are your options, as no repellents are available.

In some areas, woodchucks are considered game animals and can be hunted; trapping may also be allowed. Consult local regulations regarding these methods. Two leghold traps, #160 or #220 body grips, or live traps baited with apples may be placed near burrows. Spring is the best time to trap woodchucks.

Fumigation of burrows is another option, but none of these lethal management tools are highly effective.

As with deer, clearing brush and debris may make your land less attractive, but it may also disturb beneficial wildlife. Thus, fencing again may be the best option. Four-foot hardware cloth fence with an electric shock element can be effective. The fence’s bottom edge should be buried about 1 foot. Existing electric, high-tensile fences can be modified to deter woodchucks by adding 18-inch-high wires along the base every few inches.

Was it the Easter Bunny?

If tender vegetation is nibbled away early in the season, rabbits may be to blame. As with other pests, clearing excess plant life and using Hinder and Deer-Off may send rabbits packing. Although the deer repellents are approved for rabbits, no scientific data evaluating their effectiveness exists. Shooting and trapping may be allowed in some regions.

Banish the rabbits with 2-foot poultry wire (with 1 to 2-inch openings) enclosures. Secure the fence every few feet with sturdy wood or metal stakes; otherwise, rabbits will burrow directly into your field through the gaps. Extend the fence’s life by removing after the season.

Taming a masked bandit

If your corn or watermelons are taking a beating at night, raccoons may be the culprits. A long list of deterrents has failed; neither noisemakers, lighting systems, dogs nor repellents seem to put a stop to raccoon damage. Hunting and trapping may be allowed in some areas; generally, a number of regulations govern seasons and methods by which raccoons can be eliminated. Care should be taken in any interaction with living and dead raccoons, as rabies is common in these pests.

Once again, fencing may be the most effective control. Double-strand electric fences with wires 5 to 10 inches above ground level work well. Since raccoons are nocturnal, the electricity can be turned off during the day; however, daytime use may deter woodchucks if they also are troublesome. The prime factor drawing raccoons is sweet corn at the milk stage, so for best results, install fencing 14 or more days prior to that point.

Rascally rodents

Various other rodents are to blame for crop damage across the country. Ground squirrels are problematic for many row crops. The Oregon State University says that if you count 20 squirrels in 1 acre during a five-minute period in the spring, you can anticipate 5 percent damage from the rodents (to estimate loss, multiply the number spotted by .25). Poison baiting has proven to be the most effective treatment.

Tree squirrels, which can destroy nuts and tree fruits, can be quite difficult to manage. The Internet Center for Wildlife Damage Management (www.icwdm.org), a resource managed by several universities including Cornell and Clemson, offers numerous suggestions. Substances such as Ropel and capsaicin act as deterrents. Trapping and shooting may be permissible in some localities, but, often, any eliminated rodents are quickly replaced by new squirrels.

Photo courtesy of www.Morguefiles.Com.
Fencing that is well-secured along the base can deter hungry rabbits.

More than 20 vole species wreak havoc across America’s farmlands. Not only do they snack on crops, their burrowing and tunneling causes additional damage to plants and wrecks irrigation systems. Voles don’t bat an eyelash at fencing, repellents, noisemakers and a host of other deterrents, but zinc phosphide and anti-coagulant baits have been shown to be the best weapons.

Fencing ABCs

If you decide to invest in high-tensile, woven-wire fencing, Rutgers recommends determining what local regulations apply first. Don’t skip the planning stage; installing the right product in the most appropriate way will enhance your success in the war on wildlife.

Rigid brace assemblies, including ends, corners and gates, are crucial, and proper installation is key. The fence should be tightened to hundreds of pounds of pressure as it is erected, thus inferior assemblies and/or improper installation will not stand up to the job. A quality fence built per manufacturer’s recommendations should protect crops for two decades or longer with little maintenance required. If you decide to install a high-tensile fence, consult the Rutgers publication, “High-Tensile Wire Woven Fences for Reducing Wildlife Damage” for additional guidelines. It is available at no cost online at www.njaes.rutgers.edu/pubs.

For information specific to your area, contact your state department of agriculture, division of fish and wildlife and cooperative extension service.

Based in Greensboro, N.C., the author writes articles about horticulture, landscaping and agriculture. She has been a contributor to Moose River Media publications for three years.