FOR-57
MANAGING WHITE-TAILED DEER PROBLEMS IN KENTUCKY
ISSUED: 10-93
REVISED:
Thomas G. Barnes
Extension Wildlife Specialist

Deer are a valuable natural resource in Kentucky, providing many hours of enjoyment for the public. The white-tailed deer (Odocoileus virginianus) is the most sought after big game animal in North America. Whitetails were abundant in our country when European settlers first arrived. By 1900, however, uncontrolled hunting had reduced the U.S. white-tailed deer population to around 300,000. The deer population has since rebounded as a result of strict hunting laws, intensive reestablishment and restoration efforts, and changing habitat to favor deer. Today, it is hard to imagine white-tailed deer populations not being abundant.
In fact, in many circumstances, we have too many deer in the wrong place at the wrong time. Occasionally, the approximately 450,000 deer in Kentucky may cause unacceptable economic losses to farmers and orchard owners. High deer populations in rural areas may result in damage to orchard trees, soybean or corn fields, and vegetable crops. Deer may also hamper forest regeneration and interfere with small-scale Christmas tree production. High deer populations also contribute to the many deer/vehicle collisions on our highways. In our urban and suburban areas, high deer populations may result in damage to ornamental trees, gardens, and parks or greenways.
While most of us enjoy seeing deer, sometimes it is necessary to manage the herd in an effort to reduce the damage they can cause. Unlike chipmunks, moles, starlings, pigeons, or other nuisance wildlife, deer cannot be casually eliminated when they come into conflict with a landowner's intended land use. Thus, deer damage management becomes a social and political problem as well as a biological and logistical problem.

Animal Facts and Biology
The easily recognized white-tailed deer is the only native ungulate (hoofed mammal) remaining in Kentucky. Most people are familiar with the reddish brown summer coat and grayish brown fall and winter coat of the adult whitetail. Likewise, most people are familiar with the rust-colored fawn that is dotted with white spots. By three to four months of age, the fawn replaces this coat with a fall/winter coat. The underparts of the tail, belly, chin, and throat are white.
It is easy to tell the difference between male and female whitetails because bucks grow antlers from April through August. The growing antlers are nourished by a soft exterior tissue called "velvet." Once the antlers have reached their maximum size, the dried velvet is rubbed off and the antlers are polished during the fall breeding season. Antler size depends on the deer's age, genetics, and nutrition. White-tailed deer lack upper incisors which results in a distinctive feeding pattern that looks like the plant was torn. Rabbits and rodents, on the other hand, make a sharp, clean, knife-like cut on plants.
Whitetails breed from October through January. Peak breeding activity in Kentucky usually occurs in mid-November. Females cycle every 28 days and will remain in heat for 24 hours. One buck may mate with a number of does and no pair bonds are formed. Most deer breed their second fall, although about 40% of fawns may breed the first fall. After a gestation period of about 200 days, adult does will typically bear twins in June. Fawns will usually bear a single fawn. The reproductive potential of white-tailed deer is greatly influenced by the amount and quality of food present the preceding year. Once the fawns are born, they gain weight quickly and reach an adult weight that varies from 180 to 250 lbs.
Deer are browsing animals and over 650 different plant items have been identified in their diets. Broadleaved "weeds" or forbs are preferred food items and are eaten whenever available in the spring and summer. Most of the time deer eat the leaves, stems, and buds of woody plants because they are available year round. During the fall, acorns, beechnuts, hickory nuts, persimmon fruits, and other nuts or berries are favorite food items.
Deer can be selective feeders eating only certain plants or plant parts. However, when too many deer live in an area they will consume almost every piece of vegetation within reach to survive. Grasses are relatively unimportant in a deer's diet, although they will eat agricultural grain crops and fruit trees if these are available. The soybean plant is a highly preferred food for white-tailed deer. They also relish other agricultural crops such as corn, grain sorghum, milo, and alfalfa.
Deer are most active early in the morning and late in the evening. In most areas of Kentucky, deer will roam about 640 acres. In the mountainous east, the home range size may be as large as 1,000 acres or more. Under conditions of suitable habitat, an area of 1,000 acres may support 40 or more deer; however, the deer will travel on and off that amount of land at different times of the year looking for the best food and cover available.
Deer are habitat generalists and prefer the forest edge over dense, old-growth forests. They do exceptionally well in most parts of Kentucky because agricultural lands are mixed with timbered stream drainages and woodlots or small forested tracts. They favor brushy areas because these areas provide large amounts of cover and food.

Preventing and Controlling Deer Damage
There are no easy answers, quick fixes, or inexpensive control methods for managing deer damage problems. Each situation is different and requires a different solution. Often, a combination of techniques may produce the best results. In one Oregon study, the best protection for large-scale conifer production was to use a chemical repellent in combination with plastic flagging. Like many agricultural ventures, deer damage management must be viewed as a long-term commitment and possible investment. For consistent control, a five- to ten-year damage management program is advisable.
Urban control methods differ drastically from rural control methods because deer cannot be harvested by the general public in urban areas. In addition, urban homeowners have smaller acreages and neighbors may not tolerate unsightly fences. One way to reduce deer damage to ornamental trees is to select plants that deer do not like to eat. For more information on which plants are unpalatable to deer contact the Cornell Cooperative Extension Service, Cornell University, Ithaca, NY 14853, and ask for a copy of the fact sheet "Resistance of Woody Ornamental Plants to Deer Damage."
Deer that live in urban parks and greenways present a difficult social and political problem that will not be discussed in this publication. Contact the Kentucky Department of Fish and Wildlife Resources for assistance with these problems. Information on managing deer problems in Christmas tree plantations is available from the Kentucky Cooperative Extension Service. Ask your county Extension agent for publication number FOR-27, "Pest Control: Animals."

Harvesting Schemes
Significant deer damage usually means the area has too many deer. The proper time to take care of this problem is during the fall hunting season before the next growing season. Even if you get a permit to destroy problem deer during the summer, doing so will not help that year's soybean crop because yield-reducing damage occurs in the first 7 weeks of plant growth.
You should be aware that any agricultural field of soybeans, corn, or alfalfa that is smaller than 15 acres and located next to wooded or brushy habitats is just like a food plot to attract deer. In these cases entire fields can be destroyed. Deer present less of a problem in large soybean fields. Most damage is concentrated within 30 feet of field edges, and less than 2% of the plants will be damaged to the point where their yield will be reduced. Soybeans can withstand a removal of up to two-thirds of their leaves without affecting bean production. In some cases when the plants are less than 3-weeks old, deer browsing actually increases yield. If you can protect your soybeans until they are 4- to 7-weeks old, you will substantially reduce any potential yield losses.
Landowners should consider the following options for reducing or preventing deer damage to their crops: (1) obtain a permit from the Kentucky Department of Fish and Wildlife Resources Conservation Officer or District Wildlife Biologist to harvest antlerless deer; (2) plant a crop that is not palatable to deer; (3) plant the soybean crop early in spring so if the beans are browsed they will have time to recover (late-seeded beans may have reduced yields because they have not had time to recover from browsing); (4) plant a variety of soybeans that may have some resistance to deer browsing; (5) erect a temporary or permanent electric fence; or (6) use a chemical repellent to deter the animals.
A permit may allow you to harvest deer at times other than during the legal hunting season. Another permit may allow you to harvest extra does during the legal hunting season. When using special permits, contact local hunters in the community and assist their help. Many eager hunters would gladly harvest the extra deer and possibly pay for that privilege during the hunting season. Information on lease hunting is available from your county Extension office. This method helps you solve your damage problem, provides extra farm income, and creates good landowner-hunter relationships. The most effective, long-term, and practical solution to managing large-scale deer problems is fall hunting.

Frightening Devices
You can use a propane exploder to discourage deer from using the fields before you construct fencing. Propane cannons can be set to detonate at regular, timed intervals. It is important to set the cannons out when the plants appear above ground and continue for 4 to 7 weeks. Move the cannons every few days and alter the time when they detonate to prevent deer from becoming accustomed to the sound.
You can also use a shellcracker to frighten deer away from crops. Shellcrackers are special 12-gauge shotgun shells that use a firecracker in place of lead or steel shot. When you fire these shells, they travel 75 to 150 yards and explode in the air with a loud bang. Remember: Frightening devices will only temporarily alleviate the problem until you decide on a more permanent solution.

Fencing
If hunting is not a viable option, fencing is the other valuable tool that will keep deer away from cropland. Fencing can provide consistent and effective deer damage control. Historically, farmers used the 8-foot woven wire fence (figure 2) to control deer damage. This is an extremely expensive option and may be too costly for most agricultural use. It still remains a viable option under the right circumstances. One easy way to create a mesh wire fence is to join two 4-ft x 8-ft hog panels together supported by a 12-foot post. This fence can be slanted at a 45-degree angle (figure 3). The high end of the fence should be 6 feet from the ground and slanted so deer can walk under the fence without being able to jump over it.
An excellent alternative is to use low-cost electric fence designs. Current prices for these fences vary from 10 to 25 cents per running foot based on design and materials used. The most expensive component will be the charger. Electric fences act as a barrier and are based on the idea that deer have a tendency to go through an obstacle even though they could easily jump over or crawl under it. Upon contact with the fence, the deer receives a shock and is deterred.
While it may appear the initial cost of constructing an electric fence is high, when you prorate the cost over a number of years, it can pay for itself in increased yields. Electric fences can be either permanent or temporary. Be aware electric fences require more maintenance and are not effective when not electrified. These fences must be inspected regularly and the vegetation must be controlled to prevent grounding of the charged wires. In addition, the following guidelines will increase the effectiveness of electric fences:
Build the fence before deer damage begins. It is easier to prevent a feeding pattern than it is to break one.
Attach additional strands to the fence if deer pressure justifies the cost.
Use a voltmeter to ensure the charge is a minimum of 3,000 volts.
Use a New Zealand style energizer to supply high voltage while resisting grounding by vegetation.
Control all vegetation under the fence.
Do not place the fence directly adjacent to old woven wire fences, woody fence rows, or brushy cover that deer might normally have to jump over.
Clear a 6- to 8-foot open strip outside the perimeter of the fence.

Temporary Electric Fence Designs
These fences are relatively inexpensive to construct because they do not have rigid corner assemblies and can be made of whatever materials are around the farm. These are low-profile fences and usually have 1 or 2 strands of wire. Fence lines are strung with 50 lbs of tension. If possible, use 2 x 2 insul timbers (self-insulating posts made of eucalyptus wood) as corner posts to reduce the cost and increase the effectiveness of these fences.
The peanut butter baited fence design is made of a single 17-gauge smooth wire strung 30 inches above the ground (figure 4). The wire is connected to insulators attached to 4-foot stakes. The stakes are placed at 50-foot intervals. Attach 3-inch x 4-inch strips of aluminum foil with cloth adhesive tape at 3-foot intervals. Apply a 1:1 mixture of peanut butter:vegetable oil to the tape strips. Connect the single wire to the positive post of the energizer. The idea is to attract deer to sniff the wire with its muzzle and receive a shock that acts as a deterrent.
Another design is to use bright yellow or orange electric polytape (figure 5). Polytape is a 1/2-inch wide plastic strip that contains 5 interwoven thin wires. This design can be made more effective by coating the tape with peanut butter. The polytape should be strung 36 inches above the ground. Use a fiberglass "T" post at each corner and secure the tape to these posts using a square knot or half hitch. Set 4-foot fiberglass rods along the fence at 60-foot intervals. Attach the polytape to insulators on the rods and connect it to the positive post on the charger.

Permanent High-Tensile Electric Fence Designs
These electric fence designs should be used with pressure- treated posts that have a life-expectancy of 35 to 40 years. High-tensile electric fences are useful in protecting orchards, vegetable crops, nurseries, and other high dollar crops. These fences are powered by high voltage, low impedance chargers (New Zealand style) capable of charging 5,000 feet of fence with reduced susceptibility of grounding by vegetation. These fences use high-tensile smooth wire (200,000 psi, 12 1/2 gauge) and special accessories help to maintain a 150 to 250-lb tension so the fence can absorb the impact of running deer and spring back to its original position.
These components eliminate many of the problems associated with traditional electric fence designs, including:
The wire absorbs the impact without stretching or breaking.
A single wire is used to determine proper wire tension.
Inline wire strainers are used to tighten the wire.
Crimping sleeves are used to splice wire or fasten the ends.
Tube insulators insulate the wire from line posts, provide strength, and allow the wire to slip through during impact.
Wrap-around insulators fasten the wires at the ends and allow for continuous wire stringing outside the posts at the corners.

The 6-wire vertical high-tensile electric fence design is a modification of the Penn State 5-wire design (figure 6). The lowest wire should be 8 inches above the ground and the remaining wires are spaced at 10-inch intervals. The bottom wire is "hot" and the remaining wires are alternating ground and hot. Rigid corner assemblies (figure) must be installed. Fiberglass battens are placed at 30-foot intervals along the fence to maintain wire spacing. Eight-foot line posts are placed every 60 feet for structural support. For specific instructions on how to assemble this fence, contact the West Virginia Cooperative Extension Service, West Virginia University, Morgantown, WV 26506. Ask for publication number 814, "Deer and Agriculture in West Virginia: 6-Wire Vertical High-Tensile Electric Anti-Deer Fence."
A modification of this design is the 7-wire slanted fence. The wires are spaced 12 inches apart; the bottom wire is located 10 inches from the ground. The wires are strung along a 7-foot rail slanted up and away from the crop (figure 7). Set angle braces at 30-foot intervals. Apply 150 lbs of tension to the wires. All seven wires should be connected to the positive post on the charger and the second, fourth, and sixth wires are connected to the ground.

Other Exclusion Devices for Orchard, Ornamental, or Nursery Trees
Homeowners and small orchard owners may decide to protect individual high value trees using a plastic tree guard tube or mesh netting (plastic or 1/2-inch hardware cloth). Each tree is covered or enclosed by a device designed to prevent deer from browsing on the young seedlings (figure 8).
Sometimes deer damage valuable orchard or ornamental trees by rubbing their antlers against the tree trunk to scrape off the velvet. The Europeans have cleverly designed a physical deterrent to prevent deer from rubbing antlers on tree trunks. The structure is made from a 3- to 4-foot length of steel rebar. Weld numerous 12- to 18-inch pieces of rebar in a spiral arrangement to the original rod (figure 9). Drive the completed structure into the ground next to the trunk of a small tree. The cross pieces discourage deer from rubbing their antlers on the tree trunks.

Chemical Repellents
A repellent is a distasteful or foul-smelling chemical that an animal avoids. There are two types of repellents: area and contact. Area repellents are applied next to plants and repel by smell. Contact repellents are applied directly to the plant and repel because the animal dislikes their taste. The effectiveness of repellents depends on a number of factors including the deer's appetite, weather conditions, and thoroughness of application. Many repellents do not weather well and must be reapplied after a heavy dew or rain, or on new plant growth, to be effective. The amount of preferred food available also influences a repellent's effectiveness. If the deer population is high and under food stress, repellents will be less effective. Not every repellent will be effective in every situation.
The success of a repellent is measured by how much damage it reduces. The effectiveness of different repellents has been shown to vary from a 15% to 80% reduction in damage. You must decide if this amount is acceptable. Commercial repellents are more effective than home remedies such as human hair, soap, feces, or animal remains. These home remedies have been concocted in hopes of keeping deer out of crops, but they realistically offer little relief from the problem.
Always follow the manufacturer's directions and label instructions before applying a chemical repellent. Never apply repellents to any portion of a plant likely to be eaten by humans unless the label permits it.

Contact or Taste Repellents
Repellents containing 37% putrescent whole egg solids as an active ingredient are available as sprays or ready-to-apply powders. They are used on fruit trees prior to flowering and ornamental trees during the dormant season. These repellents should be applied to new growth and are claimed to be effective for two to six months.
Thiram is a fungicide that acts as a taste repellent. The amount of active ingredient varies from 5% to 42% depending on brand name. Thiram is used on dormant trees and shrubs, including fruit and nut trees, nursery stock, seedlings, and conifers. It can be sprayed or brushed on trees. You can make your own thiram-based repellent by combining 2 quarts of 42% thiram, 1 gallon water, and 2 quarts Rhoplex AC-33 as a sticking agent.
There is a chemical repellent registered for use on edible crops. The active ingredient is 15% ammonium soaps of higher fatty acids. It can be applied as a spray to fruit trees, vegetables, field crops, ornamentals, nursery stock, and forage or grain crops. In large agricultural fields, apply the repellent over an 8- to 15-foot strip around the perimeter of the field. You will have to reapply after a rain and every 2 to 4 weeks after initial application.
There are other commercially available repellents including those with an active ingredient of 97.5% bone tar oil, 2.5% capsaicin, and benzyldiethyl ammonium. Several research studies have shown these chemicals reduced damage by less than 35%. Before you decide to use repellents, conduct a cost/benefit analysis of all possible solutions. If you are having repeated heavy deer damage problems, it may be more cost effective to build a fence than to continually apply repellents.
Deer damage complaints and conflicts will likely continue as long as we have healthy deer populations. Perhaps the best way for a grower to co-exist with deer is to consider the benefits of the deer resource and treat deer as another crop (economic assest) of the land. By allowing regulated hunting you provide people with access to a public resource while at the same time reducing deer damage problems and reaping economic rewards. Contact your county agent for more information on lease hunting.