Deer and elk feed on grasses, shrubs and trees. They chew buds, spurs, shoots and leaves of all varieties of fruit trees. Small damaged trees may never develop into commercially productive plants. Antler rubbing may break branches and remove bark. Fencing is the best control method for severe damage; repellents may be adequate to control light or occasional damage.
A properly built and maintained fence is the most effective and the only long term solution to excluding deer from orchards. Scare devices, repellents and shooting are short term, less effective methods for protecting trees.
Repellents should be applied when deer damage is first noticed and when temperatures are above freezing. There are a number of repellent products available - human hair, soap, feather meal, blood meal, and commercial chemical repellents. The best protection for orchards with repellents is achieved by alternating several different repellents over the year to avoid deer becoming accustomed to the repellents.
Recommended commercial repellants include Deer-Away Big Game Repellent (37% putrescent whole egg solids), and Plantskydd Deer repellent (dried blood), and Bobbex Commercial Deer and Rabbit Repellent. Spray lateral branches to a height of 2 m in fall and winter, apply every 2 - 3 months, depending on deer pressure and weather conditions. Follow label instructions carefully.
Woven wire fences, although more expensive to construct than electric fences, provide the most reliable protection from deer damage. They should be at least 2.4 m high with a 15 cm wire mesh. Secure the mesh close to the ground to prevent deer from crawling underneath. The Fencing Fact sheet, Deer Exclusion Fencing for Orchards and Vineyards Using Woven Wire describes recommended construction and methods for a woven-wire fence.
Electrified deer fences, although cheaper to build than woven wire fences, have higher maintenance costs, and in general are less cost-effective than woven wire fences. Research in the Okanagan has shown that vertical fences are more effective than slanted designs. Electric fences should be 1.5 to 2.1 m high with 7-9 strands of high-tensile smooth wire at 20-30 cm spacing. Use a high-voltage energizer with this type of fence.
For further information on electric fencing, refer to the fact sheet Crop Protection and Wildlife Control Fences - BC Ministry of Agriculture.
The brochure Protecting Orchards from Deer will help growers to estimate the benefits and costs of fencing. It is also available from the Kelowna BCMA office. A complete listing of downloadable publications on fencing is found on the BCMA fact sheet B.C. Agricultural Fencing Handbook - Province of British Columbia.