Preventing deer damage with barrier, electrical, and behavioral fencing systems

White-tailed deer (Odocoileus virginianus) are responsible for damage to a variety of horticultural crops. Economic losses often require growers to implement one or more damage management methods including repellents, scare devices, hunting to control deer numbers, and fencing. A relatively small proportion of producers currently use fencing as their primary deer damage management technique due to high initial costs and other perceived shortcomings. Several fencing systems, including baited single wires, three-dimensional outriggers, and slanted and vertical fences up to 3.3 m (11 feet) in height have successfully excluded deer under some conditions, but simple designs are effective only under light deer pressure, or for relatively small (< 5 ha) areas. Low-cost fences are seldom satisfactory for protecting commercial orchards or ornamental plantings during winter, especially if snow restricts normal deer foraging opportunities. Combining electric fences with either attractants or repellents can enhance their effectiveness. Recent experiments with invisible electronic fencing systems and dogs have resulted in reduced deer damage to crops, however, additional research is needed to determine dog density per unit area for reliable protection during winter. Actual costs for fence installation vary depending on site characteristics, labor quality and costs, and sources of materials. It is important for growers to calculate the annual fencing costs for an orchard or nursery based on the anticipated life-expectancy of the fence design