Idaho’s mule deer and white-tailed deer are “edge” species, preferring to browse in open areas near forests or dense shrubs. Our urban landscapes, with their innumerable edges, are consequently very attractive to deer. On average, deer eat about 7 pounds of food—approximately 3 percent of their body weight—each day. They’re most active in the early morning and evening. Deer like to nibble, tasting first one plant, then another, and will return to your yard repeatedly if they’ve learned they’ll find good things to eat there. While they like some plants—and some stages of plant life—better than others, they’re far from fussy. Deer also drink 2 to 4 quarts of water a day, sometimes from birdbaths or water features. Females typically, they have one or two fawns each spring, although triplets are not unusual for white-tails.
Benefits and conflicts
Who doesn’t enjoy watching these graceful animals, especially with their adorable fawns at their sides? However, deer can cause extensive damage to urban landscapes, orchards, and vegetable gardens by feeding and trampling on plants and by rubbing antlers against young trees and shrubs. Young garden and landscape plants can be severely damaged or killed by these visitors’ spring and summer browsing; indeed, deer have a special yen for tender new shoots and buds. Deer will include fruit in their diet during the summer, acorns during the fall, and lichen, dead leaves, twigs, bark, and evergreen boughs in the winter.
Strategies for coexistence and control
Habitat modification: Although deer become decreasingly selective as they become increasingly hungry, there are some plants they are less likely to eat. Among the plants that deer avoid are those with a strong scent, and those with thick, leathery or fuzzy leaves, or bristly or spiny textures. Many deer-resistant plants are poisonous throughout the year or at some stages of growth. See Deer-Resistant Plants from Colorado State University for more information, or Deer-Resistant Plants from Oregon State University.
Fencing: Typically, it takes an 8-foot-tall fence—plastic mesh, wood, chain link, or wire—to keep deer from jumping into your yard. However, a 5-foot height solid fence may work because deer are reluctant to jump into an area they can’t see. Keep them from crawling under the fence by securing it close to the ground. Electric fencing—one to five wires temptingly baited with a 1:1 mixture of foil-wrapped peanut butter and peanut or vegetable oil—can effectively exclude deer from small areas. Successfully lured into being shocked, they learn to stay out. Protect individual trees or shrubs by encircling the plants with staked wire or plastic mesh. Some commercially available trunk wraps are designed to protect bark from antler-rubbing.
Frightening devices and repellents: An active dog running loose in a fenced yard can effectively deter deer. Odor- or taste-based repellents can help if they’re applied repeatedly, especially after rain or irrigation, and if the same repellents aren’t used for too long. Once deer accommodate to a particular repellent, it loses its ability to deter them. Flashing lights, for example, work briefly but deer soon learn to ignore them. If you’re spraying a repellent on a food product, be sure to check the product label to verify that that is an approved use.
Trapping: Constraints of labor and expense usually make live-trapping and removing deer unfeasible.
For more information: Wildlife Damage Management Fact Sheet Series: White-Tailed Deer, Cornell Cooperative Extension
Source: University of Idaho Extension – http://web.cals.uidaho.edu/idahogardens/2012/08/1262/