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Elk | Elk Overview | Elk Damage Assessment | Elk Damage Management | Elk Resources | Elk Acknowledgments | ICWDM | Wildlife Species Information |
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Ungulates (Deer, Elk, Moose)
Damage Assessment
Ungulate damage to various agricultural, forestry, and ornamental crops caused by feeding, trampling, and antler rubbing is an increasing problem. Deer browsing in winter on buds of apple and other fruit trees can reduce yields the following year (Austin and Urness 1989) or adversely alter the growth pattern of tree limbs (Harder 1970). Similar browsing on nursery plants and in Christmas tree plantations can reduce or eliminate their market value (Scott and Townsend 1985). Browsing of hardwood saplings and young fir trees in regenerating forests can reduce growth rates, misshape trees, and even cause plantation failures (Crouch 1976, Tilghman 1989). Damage to trees caused by antler rubbing can be severe (Scott and Townsend 1985). Small trees (1/2 to 1 inch [1.6 to 2.5 cm] in diameter at 6 inches [15 cm] above ground) with smooth bark, such as green ash, plum, and cherry, were preferred for antler rubbing by white-tailed deer in an Ohio nursery (Nielsen et al. 1982).
Objective estimates of economic loss from ungulate browsing and rubbing in orchards, nurseries, and reforestation projects are difficult to obtain. Losses in yield or tree value may accumulate for many years after damage occurs and vary with other stresses, including rodent damage, inflicted on the plants. In Ohio, growers reported average losses to deer in 1983 of $82 per acre ($204/ha) for orchards, $89 per acre ($219/ha) for Christmas tree plantings, and $108 per acre ($268/ha) in nursery plantings (Scott and Townsend 1985). Losses apparently are in the millions of dollars annually in some US states (Black et al. 1979, Craven 1983b, Connelly et al. 1987).
Deer also feed on various agricultural crops, especially young soybean plants and ripening ears of corn. Hygnstrom and Craven (1988) estimated a mean loss of 2,397 pounds of corn per acre (2,680 kg/ha) for 51 unprotected corn fields in Wisconsin. Yield reductions in soybean fields are most severe when feeding occurs during the first week of sprouting (DeCalesta and Schwendeman 1978). Elk in some areas raid hay-stacks and cattle feedlots (Eadie 1954).
Damage Identification
Ungulates do not have an upper set of incisors. Thus, twigs or plants nipped by these hoofed species do not show the neat, sharp-cut edge left by most rodents and lagomorphs, but instead show a rough, shredded edge, and usually a square or ragged break. Pearce (1947) observed that deer in the Northeast seldom browse higher than 6 feet (1.8 m) from a standing position, but are able to reach up to 8 feet (2.5 m) by rearing up on their hind legs. Elk and moose browse to a height of about 10 feet (3 m). Deer seldom browse on branches more than 1 inch (2.5 cm) in diameter. Moose and elk will gnaw the bark of aspen trees. When male ungulates rub the velvet from their antlers, the scarring is generally confined to the trunk area up to 3 feet (1 m) high (Pearce 1947).
Summary of Damage Prevention and Control Methods
Exclusion
Large wooden panels around haystacks are effective but expensive. Wrapping haystacks with plastic sheeting or netting is less expensive but effective for only 1 to 2 years. Tensar snow fence material is inexpensive and effective for many years.
Woven-wire fencing is highly effective, but expensive. Electric fencing is less expensive and almost as effective as woven wire.
Welded-wire cages up to 6 feet (1.8 m) tall effectively prevent elk damage to fruit and ornamental trees.
Vexar® and Tubex® plastic cylinders and paper budcaps effectively prevent elk damage to conifer and hardwood seedings
Cultural Methods
Alternative forage plants provide protection under limited conditions. Planting larger trees, especially conifers, is highly successful. Alternating grazing by cattle and elk provides increased amounts of nutritious forage for both on the same pasture.
Harvesting timber in large blocks (100 to 200 acres [40 to 80 ha]) promotes increased forage production and overwhelms elk with more forage than they can eat, increasing potential for adequate seedling density.
Frightening
Hazing with aircraft provides short-term and expensive control of damage to range and forage crops.
Propane exploders provide temporary (2 to 4 weeks) relief from elk damage.
Repellents
Moderately effective for short periods (2 to 4 weeks). They usually require multiple applications.
Toxicants
None are registered.
Trapping
Corral-type traps are cumbersome, expensive to erect, and of limited effectiveness.
Shooting
Special hunts designed to reduce local elk numbers are of limited effectiveness.
Selective harvest of individual offending elk may provide relief from localized damage.
Other Methods
Some western states compensate landowners for damage by elk to agricultural crops.
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Elk | Elk Overview | Elk Damage Assessment | Elk Damage Management | Elk Resources | Elk Acknowledgments | ICWDM | Wildlife Species Information |
