Deer Management in New England Orchards
Alan Eaton, UNH Cooperative Extension
Deer can cause serious injury in New England orchards. White tailed deer is native to our region, and is abundant in most orchard growing regions. They browse orchard trees at any time of year, but feeding is especially intense in late winter and spring. In late winter, deer have depleted most or all of their fat reserves and are starving. The bucks in particular have their highest food consumption in spring. When the new growth appears on fruit trees, deer can replenish their reserves.
Feeding removes fruit buds, leaves and shoots, so it can affect both this season’s crop and the form & structure of the tree (and thus its productivity in future years). They will heavily browse what they can reach, which is typically the lower 6 feet of a tree. As we shifted from growing seedling trees to semi dwarf and dwarf trees, we shifted an increasing percentage of the fruit-bearing area to within reach of browsing deer. Fruit tree buds and foliage are highly palatable to white tailed deer.
Unlike rabbits and hares that have both upper and lower incisors, deer have just lower incisors. This means that twigs that have been browsed by deer appear somewhat ragged, while those browsed by hares & rabbits look cleanly sheared off. Another clue to the identity of the browser is the height at which damage occurs, and the hoof prints in the soil or snow.
Deer tend to be night active during the fall hunting season, but shift back to some daytime activity in winter, spring and (especially) summer. Deep snow in winter causes deer to congregate in “deer yards” --- thick patches of conifers with lower snow depth. If a deer yard is close to your orchard, large numbers of deer could congregate and feed there during the winter.
Most does give birth around May 25th to June 15th and often select tall grass in which to hide their newborn fawns. If they select your orchard as the birth site, it becomes their center of activity for a couple of weeks.
Deer populations in New England are no longer controlled by wild predators. The state Fish & Game departments carefully regulate deer populations by modifying hunting regulations. To them, deer are an important resource that brings in funds (hunting license revenue). But they also recognize the damage that deer do to agricultural crops, and often work with growers to reduce problems. This can be by offering shooting permits, sharing in the cost of fencing, or other methods.
Fencing can be nearly completely effective, if the fence is high enough and well-constructed. The materials and labor required can be expensive, but sometimes there are cost-sharing programs offered to assist. Fencing restricts movement of equipment and people, so it is important to carefully consider where to place gates. If you leave gates open, deer learn to walk in, thereby defeating your investment. Both wire and plastic mesh fencing options are available. In general, an 8 foot or higher fence is required to keep out deer, but some electric (either vertical or slant models) can be fairly effective at lower heights. A catalog can provide much more information on options. Some suppliers have excellent publications contrasting the options and their effectiveness. (see references)
Electric fences are most effective if they are baited, then energized immediately after being erected. The most common method for deer is to apply peanut butter to strips of aluminum foil, and drape them (sticky side in) over the fence at about at 40 inch height. By licking the tasty treat they can smell, deer quickly learn that the fence can hurt them, and they keep away. Electric fences can have limited effectiveness during periods of deep snow (when the deer’s feet don’t really reach the ground), but there are designs that provide a strong shock even in that situation, including using a bipolar fence charger.
Repellants are short term tools that can help deter deer from trees that have no other protection. Some repel by taste, and others do so primarily by odor. Growers can hang soap bars to deter deer feeding. Usually this is done on young trees. Keep the soap in its protective wrapper. You can drill a hole through it and attach a loop of string, or use a mesh bag to hold the bar (still in its wrapper). The effective distance is several feet. Do not tie the bag around a branch, or it will restrict growth. Instead, use a loose loop. Soap bars are most effective if placed about 40 inches high. Bars can last for a year, sometimes longer. There are also soaps that can be sprayed on, like Hinder. Effectiveness may be 2-4 weeks, and you’ll have to re-apply it after a rain. Big game repellant is a commercial product made with putrescent egg solids. It works both by odor and taste. Most labels say it is for use before flowering. One application may work for 2 months or more. Capsaicin is available in several forms. Do not apply it after flowering. You can mix the material with an anti-transpirant to make it last longer. The fungicide thiram is a taste repellant. Some growers use human hair bags as odor repellants. Onion bags or similar mesh bags make good containers. You might get some at a local barber shop.
Landowners can sometimes employ shooting to reduce local deer pressure. Regulations vary from state to state, and growers who suffer serious losses can sometimes acquire special shooting permits, even outside of normal hunting seasons. Shooting reduces damage partly by eliminating individual deer who have learned to feed in your orchard, and partly from scaring away other deer in the local herd.
Some orchardists use trained dogs and “invisible fencing” to keep deer out of the orchard. One major impediment to using this in New England is the very cold winter weather. Many dog owners would think it cruel to leave the animal outdoors (even in its house) in very cold conditions.
Sources of Help
USDA Wildlife Services staff are available to assist with a variety of wildlife damage issues, including voles. Their telephone number for New Hampshire & Vermont growers is (603) 223-6832. For growers in Connecticut, Massachusetts and Rhode Island: (413) 253-2403. For Maine: (207) 629-5181. The website is http://www.aphis.usda.gov/wildlife_damage/
Two local companies with experience and helpful information on fencing and bird netting options are Wellscroft and Orchard Equipment Supply Company. Wellscroft Fence Systems is in Chesham, NH, and many fencing options are shown in their catalog online. www.wellscroft.com 1-855-327-6336.
OESCO is located in Conway, Massachusetts and has been very helpful to many orchardists in figuring out how to set up and what to order for bird netting. Their website is at www.oescoinc.com and telephone number is 1-800-634-5557. They also have a detailed catalog online.
There are other companies that can help, too.
One on line reference that is still useful, but needs to be updated, (1991) Controlling Deer Damage In New England Orchards by Bill Lord. https://extension.unh.edu/resources/representation/Resource000006_Rep6.pdf
Aluminum foil bait on electric fence, Alan Eaton
Making peanut butter bait with aluminum foil, Alan Eaton
Deer-browsed apple twig, Alan Eaton
Soap bar in mesh bag to repel deer feeding, Alan Eaton
Slanted deer fence, Alan Eaton
Wire mesh vertical deer fence, Alan Eaton
plastic mesh vertical deer fence, Alan Eaton