In Princeton, N.J., an area ransacked by deer, fencing is considered the first line of defense. On her own in-town property, landscape architect Louise Schiller doubled up with a neighbor to cordon off their combined plots of land, which allowed them both a better view. But the need for a utilitarian 6-foot fence—the maximum height allowed in her neighborhood—didn’t stop her from incorporating other architectural elements. The fence is hidden in shrubbery, and at the entry garden it attaches to a brick wall and wood trellis. “It helps if the deer can’t see into the garden, so I recommend planting a mixed evergreen and deciduous border inside the fence,” she says, adding that clients with large properties sometimes install two parallel fences roughly 7 feet apart. While doubling the expense, it decreases the odds that deer will jump the fence.
Even the best fencing material needs to be well-fortified. Posts in sleeves should be spaced no more than 20 feet apart, ground stakes 4 to 5 feet apart, says Daniel Rich, president of Benner’s Gardens in Conshohocken, Pa., which distributes and installs deer fencing nationwide. “Deer will try to get in by getting their head underneath and pushing up under the fence,” Rich says. “If one gets through it’s like the dinner bell—a signal for the rest of them to follow.” Tension cables—one at the top and one 30 inches from the ground at the impact zone—are also necessary to deflect deer and falling tree limbs.
Deer Deterrents For avid naturalists, fencing’s downside is that it keeps all wildlife away. But there are other options. Offensive odors, in the form of sprays, store-bought composted manure, or even lion dung collected from the zoo are effective, though high-maintenance. According to Trevor Price, CEO of Pleasantville, N.Y.-based Nature Technologies, an integrated pest management company for deer that services the eastern seaboard from Massachusetts to Washington, D.C., predator sprays, hot pepper sprays, and rotten egg sprays are the most effective. (Wear rubber gloves to apply the hot pepper, and don’t spray the rotten egg solution on the day company is expected.) Mint, cinnamon, and rosemary sprays smell nicer but don’t work as well. “The main thing is to change it up,” Price says. “Buy three different sprayers, label them, and rotate the solutions every three weeks.”
The company, which has a research arm at Cornell University, recently patented DeerTech 880, an ultrasonic device that is said to frighten deer. The box, about 17 inches in diameter and 4 inches high, emits a high-frequency signal at 110 decibels through strategically placed speakers running on low-voltage electricity. For the deer, “it’s like going to a nice French bistro and having five jet engines surround them,” Price says. “They use their hearing to protect themselves against predators, and the loss of it makes them extremely afraid.” Price says that at least two deterrents are always in place on clients’ properties. “We’ll augment the ultrasonic devices every couple of weeks with predator scents or a light that makes plants look diseased,” he says. “The logic is that they turn away and don’t eat.” Whether the battle is fought with a high-tech sound system or low-tech lion dung, staying one step ahead of the deer will require creativity and persistence. That is, until wildlife management experts figure out how to safely decrease their numbers.
Cheryl Weber is a writer in Lancaster, Pa.
