Deer Factsheet

White-Tailed DeerOver the past 30 years, especially the pastdecade, populations of white-tailed deer(Odocoileus virginianus) have increaseddramatically throughout the Northeastand in many midwestern and westernstates. In the 1900s New York’s deer pop-ulation rebounded from about 20,000 tomore than 1 million. Increases in deerabundance can be attributed to changes inhabitat, including reversion of abandonedfarm fields to forest, and shifts in humanpopulation to rural and suburban areas.Both of these trends create open andforested habitat preferred by deer. Inaddition, decisions by landowners to pre-vent hunting have made many areas offlimits to hunters, allowing deer popula-tions to increase. Although the recovery ofdeer populations from only about500,000 nationwide in the early 1900s tomore than 15 million today is considereda wildlife management success story,many people increasingly view the situa-tion with mixed feelings.

General BiologyThe white-tailed deer is the most wide-spread and abundant member of the deerfamily and one of the best recognizedlarge mammals in North America. White-tailed deer are a valuable component ofour wildlife heritage and are avidly soughtby hunters, photographers, and natureobservers. The buck, or male deer, stands3 to 3 1/2 feet tall at the shoulder, weighs125 to 200 pounds, and grows antlersthat are shed annually. Does are smallerand lighter than males and lack antlers.

Deer are red-brown during summerand grow brown-gray winter coats each

fall. Fawns (deer that are less than oneyear old) typically weigh 4 to 8 pounds atbirth and have red-brown hair with whitespots, which they lose as they grow theirfirst winter coat.

White-tailed deer breed from mid-September through late February, and thepeak of the breeding season, or rut,occurs in November. Fawns are born inthe early summer after a 200-day gesta-tion period. In their first pregnancy, doesusually give birth to a single fawn, thoughtwins are common in later years if food isabundant.

Bucks begin to develop antlers inApril, and the antlers grow until Augustor early September. The size of the antlersdepends primarily on age and nutrition;older bucks typically have larger antlers.

Growing antlers are covered with a skincalled “velvet.” This skin is covered withsoft hairs and contains blood vessels thatsupply nutrients to the growing antlers.When the antlers stop growing the velvetdries and is shed or rubbed off by thebuck as he polishes his antlers onsaplings, shrubs, or rocks. Bucks shedtheir polished antlers each winter inpreparation for the growth of a new set.

Habitat and Food HabitsDeer live on the forest edge rather than incontinuous areas of mature forest. Theyprefer mixed conifer-hardwood forests,shrublands, and old fields with activecropland nearby. This rich mixture of vegetation produces abundant food and

Paul D. Curtis and Kristi L. SullivanCornell Cooperative Extension, Wildlife Damage Management Program

Wildlife Damage Management Fact Sheet Series

White-Tailed Deer, Wildlife Damage Management Fact Sheet Series, Cornell Cooperative Extension, Ithaca, N.Y. ©2001 by Cornell University.

cover. Deer are very adaptable, however,and greater numbers are living in subur-ban neighborhoods, which have a combi-nation of open lawn, succulent summergardens, plentiful ornamental shrubs, andpatches of forest cover.

Deer feed primarily on grasses, forbs,crops, leaves, twigs, and buds during latespring and summer. They forage on mast(e.g., beechnuts, wild cherry seeds, andacorns) during fall and concentrate almostentirely on twigs and buds during winterand early spring.

The amount of food that a deer mustconsume daily depends on its gender andbody weight and the season. In general,deer consume 3 percent of their bodyweight each day. Therefore, a buck weigh-ing 125 to 250 pounds requires from4,000 to 6,000 calories each day, whichcan be obtained from 4 to 10 pounds ofgrass, forbs, and twigs.

Description of Damage

Homes and GardensDeer frequently feed on flowers, fruits,and vegetables and the buds and twigs offruit trees and ornamental shrubs.Damage to landscape plantings and orna-mentals may occur at any time of year butis usually most severe in the late winterand early spring when other food suppliesare limited. Damage to fruit trees maycause both the immediate loss of the cropand residual tree injury that leads toreduced yields in the future. Deer brows-ing may permanently disfigure ornamen-tal trees.

Forests and Wildlife HabitatDeer can also affect their own habitat andthe abundance of other wildlife species.Overpopulation can profoundly influencethe presence, absence, and abundance ofplants and other wildlife. In many forests,over-browsing of tree seedlings createsopen, park-like stands that have little orno vegetation near ground level. Insteadof a diversity of woody and herbaceousplants, the ground surface may be domi-nated by ferns, grass, and woody shrub ortree species that are not preferred by deer.Wildflowers preferred by deer, such asvarious species of Trillium and Canadamayflower, may be reduced in abundanceor eliminated completely from forestswhere deer densities are high.

Reduction of the understory, whichgives forests a park-like appearance,removes important nesting and feedingsites for some forest songbirds. Nesting inmore open forests can make bird eggs andnestlings easier for predators to detect.Some species may leave the area, whereasothers will be less abundant than theyonce were. In addition, other wildlife,such as squirrels and chipmunks, mustcompete for acorns, a food preferred bydeer.

Deer prefer certain plant species overothers and frequently feed on economical-ly valuable tree species. For example, theyprefer oak and sugar maple seedlings, aswell as acorns, over less palatable specieslike American beech and striped maple.Thus, less marketable species are morelikely to survive to maturity, replacingmore valuable trees. This change inspecies composition will have dramaticeffects on our future forests and forest-related industries.

Economic ImpactsAnnual estimates of deer damage arereported to exceed $2 billion nationwide,including $1 billion in car damages, morethan $100 million in agricultural cropdamage, $750 million in damage to thetimber industry, and more than $250 mil-lion in damage to metropolitan house-holds (e.g., landscape plantings). Theseestimates are conservative, and it is oftendifficult to obtain reliable statistics forwildlife-related losses.

Identifying DamageDeer feeding damage is readily distin-guished from that caused by rabbits orrodents. Whereas rabbits or rodents leavea clean-cut surface, deer lack upper inci-sors and leave a ragged, broken end onbrowsed branches. Another indication isthe height of the damage from the ground(up to 6 feet), which often rules outsmaller mammals.

Laws and RegulationsDeer are classified as game animals andmay be killed only during legal huntingseasons by persons holding a valid biggame license. Under section 11-0521 ofthe New York State Conservation Law,however, the Department of

Environmental Conservation (DEC) canissue permits allowing landowners to killdeer when they become a nuisance orharm property. If sufficient damage is evi-dent, the DEC may issue crop damagepermits for the harvest of a specifiednumber of deer outside the regular hunt-ing season. The use of damage permitscan be time-consuming, however, andoften doesn’t greatly reduce the damage.

The DEC also operates the DeerManagement Assistance Program (DMAP).Antlerless deer tags are available tolandowners who desire increased harvestsof deer to meet management goals ontheir property. DMAP includes agricultur-al lands and municipalities as well asforested areas. The program can be usedto decrease crop damage, reduce urbanand suburban deer populations, protectrare plants, ensure adequate forest regen-eration, or improve the quality and com-position of a deer herd. For agriculturalareas or municipalities no minimumacreage is required to participate in theprogram. A minimum of 200 acres isrequired, however, where forests andother natural vegetation are being dam-aged, and the landowner must have amanagement plan for the property. Onproperties where enrollment in the pro-gram is intended to improve recreationalopportunities by improving herd quality(e.g., quality deer management), a mini-mum of 1,000 acres is required.

Preventing Damage

Population ControlAlthough repellents and fencing are theprimary techniques used to address site-specific deer damage problems, thesemethods will not decrease damage on acommunity-wide scale. Deer populationswill increase if mortality is low and foodis abundant, and they can double in sizeevery two to three years.

Although the annual hunting season isan effective way to reduce deer popula-tions and thus damage in rural areas,buck-only harvests cannot reduce or sta-bilize deer numbers. Where possible,landowners suffering damage shouldencourage or require hunters to harvestsufficient numbers of does (within thelegal limits). Harvesting female deer isessential to reducing deer numbers anddeer damage. In suburban areas where


hunting may not be practical, some otherform of mortality may be required to sta-bilize herd growth. Reproductiveinhibitors are currently experimental anddifficult to apply across areas of severalsquare miles.

Choice of Landscape PlantingsIn some cases damage can be reduced byselecting plant species that deer don’t pre-fer. When deer densities are high or natu-ral foods are limited, especially in thewinter or early spring, deer may browseon species they otherwise would not eat.When planting species that deer finddesirable, be aware that they will almostcertainly require protection if deer arepresent in the landscape. A detailed listingof woody plants and their relative resist-ance to deer browsing is available in theCornell Cooperative Extension fact sheetResistance of Woody Ornamental Plants toDeer Damage. This list can also be foundin Reducing Deer Damage to Home Gardensand Landscape Planting (see References).No plants are completely deer-proof, andhungry deer will consume plants thathave little nutritional value.

Scare DevicesA variety of frightening devices, includinglights, whistles, loud noises, and scare-crows, have been used to prevent deerdamage. Audio and visual scare devicesare not recommended around the homeor near urban or suburban areas, howev-er, because of disturbance to neighbors,possible violation of noise ordinances,and lack of effectiveness. Deer habituateto scare devices after a few days of expo-sure.

RepellentsRepellents can help prevent deer fromfeeding on crops or landscaping plantsand are most effective when integrated ina damage abatement program thatincludes one or more other techniquessuch as fencing and population manage-ment. Repellents are best for smallorchards, gardens, and ornamental plant-ings around the home. Their utility is lim-ited for row crops, forages, and otherlarge acreages because of high costs, limi-tations on use, and variable results. Applyrepellents at the first sign of damage toprevent deer from establishing a feedingpattern.

Repellents fall into two broad cate-gories—those that repel by taste andthose that repel with a disagreeable odor.Most deer repellents can be applied as aspray to ornamental shrubs and nonbear-ing fruit trees. Hinder, an ammoniumsoap-based repellent, and Deer-Off, aproduct that incorporates putrescent eggsolids, are the only repellents currentlyapproved for use on garden vegetablesand fruit-bearing trees during the growingseason.

The effectiveness of repellents dependson the number of deer, feeding habits,and environmental conditions. If deer arevery hungry and other food supplies arelimited, repellents may not work. Somedamage must be tolerated with the use ofrepellents, even if browsing pressure islow. Young trees should be treated com-pletely. On older trees, treat only terminalgrowth that is within reach of deer (up to6 feet above ground). Growth thatappears after treatment may need to besprayed again. Repellents should beapplied when precipitation is not expect-ed for 24 hours and temperatures willremain between 40° and 80° F for thatperiod. Research trials have shown thatodor-based products usually outperformtaste-based materials. No commercialrepellent is 100 percent effective, andunder heavy deer browsing pressure thebest materials must be reapplied aboutevery five weeks. This may limit their usein areas that have deep snow and below-freezing temperatures during winter.

The deer repellents listed in Table 1 aregrouped by active ingredient and includea brief description of use, applicationrates, and costs. Product labels provide allnecessary information on use and must befollowed to meet legal requirements andachieve maximum success. The activeingredients are shown in parentheses afterthe trade names. Cost estimates are pro-vided for comparative purposes. “Homeremedies” such as tankage, soap, bobcaturine, and human hair may act as repel-lents. However, because both state andfederal regulatory agencies prohibit thecommercial use of products not registeredby the Environmental Protection Agency(EPA), we do not recommend them.

FencingIf deer densities are high, tolerance ofdamage is minimal, or particularly valu-

able plants need to be protected, fencingalone or fencing plus repellents may bethe best option. Many different fencedesigns are available; the one you selectmay be based on cost-effectiveness, aes-thetic considerations, or ease of construc-tion.

ROPE FENCING

A cotton rope fence used with a repellentis particularly useful for preventing deerbrowsing in flower beds or small veg-etable gardens; this combination of a visu-al barrier and odor repellent can reducebrowsing considerably during the growingseason when alternative foods are avail-able. The fence can be constructed byinstalling 3- to 4-foot posts around theperimeter of the beds. Attach cotton cordor rope at a height of about 30 inches.Spray an odor-based repellent directlyonto the cotton rope or on strips of cottoncloth tied to the rope at 3- to 4-foot inter-vals.

SNOW FENCING

Snow fences can be used during the win-ter and early spring to protect smallgroups of trees or shrubs. Although notan absolute barrier, a snow fence mayeffectively deter deer from entering smallareas (a circle 20 yards in diameter).

PLASTIC BIRD NETTING AND WIRECAGES

Plastic netting and wire cages can be usedto prevent deer browsing of individualplants or small plantings. Both alterna-tives are inexpensive and can be aestheti-cally pleasing. Plastic netting can bewrapped around individual shrubs duringthe winter and early spring. The netting isusually invisible from a distance.Although deer may browse any portion ofthe plants that extend beyond the netting,damage is greatly reduced. Plastic nettingcan also be wrapped around clumps offlowers in early spring when other foodsupplies are most limited and deer aremost likely to cause damage.

OFF LIMITS CROP PROTECTION SYSTEM

The Off Limits Crop Protection System isan invisible fence design that combineswire, a power unit, and receiver collarswith highly active, properly trained dogsthat are able to withstand harsh winterconditions. The system was field-tested inapple orchards in central New York, using


Table 1. Repellents

Plants for Length of Repellent Formulation Which Registered How to Apply Effectiveness Cost Remarks

Deer Away/Big Game Primarily Fruit trees before Spray on all Minimum of five 1-gallon Used extensively inRepellent (37% odor-based flowering; ornamental susceptible weeks with heavy liquid kit: western conifercommercial and Christmas trees plant parts. feeding pressure about $26 plantations. Hasputrescent egg solid) been reported to be

greater than 85 percent effective in some field studies.

Deer-Off Repellent Combination odor Flowers, grass, bulbs, Apply to all leaves, About five 1-pint kit: Spray (3.1% egg and taste-based ornamental shrubs, stems, and weeks with about $28; solids, 0.0006% product; available edible crops, plants, branches at onset heavy feeding makes aboutcapsaicin, and as spray seedlings, trees of deer damage. pressure 1 gallon of0.0006% garlic) spray

Hinder (ammonium Odor-based Home gardens, Apply directly. About four weeks; 1 gal. liquid: One of the fewsoaps of higher fatty ornamentals, annual varies owing to about $40 repellents registered acids, 13.8%) and perennial flowers, weather and appli- for use on edible

fruit trees until one cation technique; crops. Can be paint- week before harvest reapplication may ed full strength on

be necessary after the bark of trees toheavy rains. prevent rabbits from

chewing the bark. Compatible with most pesticides.

Miller’s Hot Sauce Taste-based Ornamentals, fruit Backpack or — Hot Sauce Weatherability can beAnimal Repellent and nut trees, bushes, hand-pump and Vapor improved by adding(2.5% capsaicin) vines, and hay bales spray on all Gard: about an antitranspirant

stored in the field; susceptible $80 and $30 such as Nu-Film-17can also protect plant parts. per gallon, or Vapor Gard. The vegetable crops if respectively 10x and 100x concen-sprayed before trations approved fordevelopment of ornamentals haveedible parts effectively prevented

both deer and elk damage to trees. Do not apply to fruit-bearing plants after fruit set.

Nott’s Chew-Not Fungicide that Dormant trees and Spray or paint — 2 gal. 42% Add adhesives such(20% thiram) acts as taste-based shrubs on individual percent as Latex 202-A or

repellent; liquid trees. thiram: Vapor Gard to formulation about $50 mixture to increase

its resistance to weathering. Thiram-based repellents also protect trees against rabbit and vole damage.

Tree Guard (0.20% Taste-based; Shrubs, ornamental Spray on all About two about $40 This material dentonium benzoate) ready-to-use plants, conifers, and susceptible weeks with may not protect

spray nonbearing deciduous plant parts. heavy feeding yews from deer trees; not intended pressure damage duringfor use on food or winter.feed crops


two dogs per 12 to 15 acres of orchard.The system is not a complete barrier, sosome level of browsing must be tolerated.An invisible fence may also be effectivefor protecting small orchards, gardens,and ornamentals around the home. Thesystem will work best if the dog (or dogs)is kept outdoors at all times. In addition,the breed of dog selected must be highlyactive and willing to chase deer.

TEMPORARY ELECTRIC FENCING

Temporary electric fences protect flowerand vegetable gardens during the growingseason. They are easy to construct, do notrequire rigid corners, and use readilyavailable, inexpensive materials. Installfences at the first sign of damage to pre-vent deer from establishing feeding habits.Use only UL-approved fence chargers andnever connect fences directly to house-hold current. Temporary electric fencesrequire regular inspection and mainte-nance.

Electric fences can be more effective ifused along with an attractant or repellent(Figure 1). To use peanut butter as anattractant, attach 3-x-4-inch foil strips tothe wire at 3-foot intervals, using 1-x-2-inch strips of cloth adhesive tape. Applya 1:1 mixture of peanut butter and veg-etable oil to the foil strips, fold the foilover the wire, and secure with adhesivetape. Deer are attracted by the peanutbutter, which encourages them to makenose-to-fence contact. After beingshocked, they learn to avoid fencedareas. Repellent, sprayed on cloth stripsand tied to electric fencing, can alsoincrease the effectiveness of electric fenc-ing and has been found to be even moreeffective than peanut butter. The additionof an offensive odor reinforces the physi-cal shock of the fence.

PERMANENT HIGH-TENSILE ELECTRICFENCING

High-tensile fencing can provide year-round protection from deer damage.Many designs are available to fit specificneeds. A seven-wire design with the firststrand 8 inches above the ground is rec-ommended (Figure 2). All require strictadherence to construction guidelines con-cerning rigid corner assemblies and fenceconfigurations. Frequent inspection andmaintenance are necessary. High-tensilefences have a 20- to 30-year life expectancy.

PERMANENT WOVEN-WIRE FENCING

Permanent woven-wire fences are the bestdeer barrier. They are used for year-roundprotection of high-value crops subject tointense deer feeding pressure. Thesefences are expensive, difficult to con-struct, but easy to maintain. Woven-wirefences are used most often to protectorchards or nurseries where the high cropvalue, perennial damage, acreage, and 20-year life span of the fence justify the ini-tial cost. Woven-wire fences can be usedaround the home to protect large gardensor as cages around individual trees orgroups of trees. Woven-wire fencing costs$6 to $8 per linear foot. Barrier fencesshould be at least 8 feet high, and theirheight can be increased to 10 feet usinglarger poles and two strands of smoothwire.

GATES AND CATTLE GUARDS

Whenever fencing is used, it is importantto incorporate functional gates or cattleguards to prevent deer from enteringfenced areas via roadways. Gates shouldbe closed following each entry and exit.To avoid the inconvenience of openingand closing gates, cattle guards may beinstalled at gate entrances. In a study con-ducted in Ohio, researchers found thatcattle guards reduced deer crossings by atleast 95 percent. Fencing should beextended along each side of the cattleguard to prevent deer from crossing alongthe sides.

Figure 2. Seven-wire vertical deer fence


Figure 1. Peanut butter fence

10’ Wood post10’ Wood post

8’ Line post

Human Health and SafetyHigh populations of deer may result innumerous deer-vehicle collisions and posea serious threat to motorists. It is estimat-ed that each year in the United States29,000 people are injured and more than200 lose their lives in deer-vehicle colli-sions. More than 50,000 deer-vehicle col-lisions are estimated to occur in New Yorkeach year. Because many incidents gounreported, the actual number of colli-sions is difficult to ascertain. Defensivedriving is the only way to reduce the riskof having a deer-vehicle accident.Research in the United States has indicat-ed that deer whistles and other ultrasonicdevices are ineffective. About two-thirdsof deer-vehicle accidents occur duringOctober, November, and December, espe-cially in the early morning and at dusk. Ifit appears that you will collide with adeer, do not swerve to avoid the animal.More human injuries occur when driversswerve to avoid deer and instead collidewith roadside obstacles or vehicles in theopposing lane than if they hit the animal.

Deer have been implicated in the dis-tribution and transmission of Lyme dis-ease. According to the Centers for DiseaseControl, there were more than 16,000cases of Lyme disease nationwide in 1998,up from approximately 2,000 cases in1987. New York State had 3,325 cases ofLyme disease in 1997, the highest numberof reported cases in the United States, fol-lowed by Connecticut, Pennsylvania, andNew Jersey. Lyme disease has reached epi-demic proportions on Long Island and inportions of the lower Hudson Valley.

Deer serve as one of several potentialhosts for the black-legged tick (Ixodesscapularis), which transmits the bacterialspirochete Borrelia burgdorferi that causesLyme disease. Larval and nymphal tickscommonly feed on whitefooted mice andother mammals and birds. Adult ticksprefer deer as their host, although theymay also occur on medium-sized mam-mals such as raccoons and opossum. Tickabundance has been found to be positive-ly correlated with deer density.Individuals who are active outdoors, par-ticularly hunters who handle and trans-port deer, should examine themselves andtheir clothing frequently for deer ticks. If

you are bitten by a tick, consult your doc-tor. In order to transmit Lyme disease,ticks must be attached to a person for atleast 24 hours, so frequent inspection andremoval of ticks is the best prevention.

References

PublicationsCraven, S., and S. Hygnstrom. 1994.

“Deer.” In Prevention and Control ofWildlife Damage. S. Hygnstrom, R.Timm, and G. Larson, eds. Lincoln:University of Nebraska CooperativeExtension.

Curtis, P. D., and M. E. Richmond. 1994.Reducing Deer Damage to Home Gardensand Landscape Planting. Ithaca, N.Y.:Cornell Cooperative Extension andDepartment of Natural Resources.

DeNicola, A. J., K. C. VerCauteren, P. D.Curtis, and S. E. Hygnstrom. 2000.Managing White-Tailed Deer in SuburbanEnvironments: A Technical Guide. Ithaca,N.Y.: Cornell Cooperative Extension.

Fargione, M. J., P. D. Curtis, and M. E.Richmond. 1991. Resistance of WoodyOrnamental Plants to Deer Damage.Home-Grounds-Garden Fact Sheet800.00. Ithaca, N.Y.: CornellCooperative Extension, College ofAgriculture and Life Sciences.

Henderson, F. R., and C. Lee. 1992.Controlling Deer Damage. Manhattan:Kansas State University CooperativeExtension Service.

VideosSuburban Deer Management: Voices, Views,

Visions. 1993. 28 min. Ithaca, N.Y.:Cornell Cooperative Extension.

Whitetails at the Crossroads. 1996. 30 min.Ithaca, N.Y.: Cornell CooperativeExtension.

©2001 Cornell University

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Deer illustration by John Sidelinger

Figures 1 and 2 from Hygnstrom, S., et al. 1994

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Deer Factsheet