Skip to main content

Deer and Elk Damage and Management

Elk and deer (two ungulate species) cause the most widespread damage to forest resources. Elk may trample or pull seedlings without well-established root systems out of the ground. Browsing elk often splinter woody stems. During the spring, the stems may be stripped of bark below where they break the stem. Deer damage inflicted on seedlings is similar to elk damage. Woody stems are often splintered and the bark is stripped from twigs. New buds are generally clipped back to the previous year's growth. Deer do not pull seedlings as frequently as elk and their damage rarely occurs above 6 feet.

Damage Management Methods

  • Planting seedlings immediately after a site is disturbed (e.g., by harvesting the trees) before ungulates become accustomed to foraging in that area—economical but not always feasible; ineffective where surrounding areas contain large ungulate populations.
  • Hunting to suppress deer populations—often impractical to solve specific problems.
  • Fencing to impede ungulate movements—can be cost prohibitive to install and maintain.
  • Tubes and other individual barriers—can be expensive, but when properly installed, tubes can protect seedlings from most wildlife species. Where ungulate populations are high and consistent, individual barriers may be reasonable long-term alternatives to reduce browsing.
  • Frightening devices, such as propane cannons and scarecrows—generally ineffective.
  • Chemical repellents—will deter ungulates, but rarely for prolonged periods. Thus, repeated applications are generally necessary.

Research

Traditional frightening devices, as listed above, are generally ineffective to deter ungulates for prolonged periods. However, devices activated by an animal's presence are generally more effective than permanent or routine displays. Further, a device affixed to an individual animal may generate responses from those individuals, and possibly from accompanying animals of the same species (conspecifics). For example, a device affixed to a matriarch elk that activates a signal (e.g., strobe and siren) and after a couple seconds delivers a mild shock to the matriarch may be very effective in inhibiting this animal from remaining in a protected site. Accompanying conspecifics pairing these signals with distress displayed by their leader also may avoid the area.

Electric collars and ear tags have shown promise for deterring cattle from protected areas, such as riparian zones. Although effective, current technology prohibits operational use of these devices to deter deer and elk from target areas. Technology more applicable for prolonged use with these animals is being pursued by field station scientists.

An improved understanding of deer and elk foraging ecology may help to reduce browsing on establishing seedlings. All plants contain toxins, and the amount of toxin an animal can ingest depends on the kinds and amounts of nutrients and toxins in the forage. Field station researchers are trying to determine if nutritional status of deer and elk affects their preference for Douglas-fir seedlings. Supplemental energy and protein increases the ability of animals to eat foods that contain toxins. Thus, supplemental nutrients offer the potential to increase intake of plants habitually avoided or to decrease intake of plants habitually eaten. Other, studies are investigating potential to select for western red cedar genotypes that may be less preferred by deer because of high terpene concentrations.

Field station biologists are also working to identify feasible approaches to exclude animals from sites. Alternative fence designs have been investigated. In addition, scientists at the station routinely evaluate efficacy of marketed repellents. Concurrently, scientists are conducting parallel behavioral and chemical assays to identify potential natural aversive agents for new repellents.

*the above discussion is summarized from NOLTE, D. L. 2003. Managing ungulates to protect trees. Western Forester 48(4):14. 76K

NWRC Publications

Note: The legal status of wildlife species and subspecies may vary by state. Some wildlife damage management methods mentioned here may not be legal, permitted, or appropriate in your area. Please check with personnel from your state wildlife agency and local officials to determine if methods are acceptable and allowed.
Bears | Deer/Elk | Mountain Beaver | Pocket Gopher | Vole, Hare, Rabbit & Porcupine

Corvallis, Oregon Field Station Page

Complementary Content
${loading}