There are many garden pests whose depredations range from mildy annoying to deeply disheartening, but in the piedmont there are three archpests: white-tailed deer, eastern cottontail rabbits, and pine voles. Shortly after we moved into this house ten years ago, it became clear that before we would have any success gardening, we would need to deal with this triumvirate of enemies.
White-tailed deer (Odocoileus virginianus)
I read somewhere that there are more white-tailed deer alive today than at any time since Columbus. Not as many Americans hunt them these days, and regrowth of the eastern forest (compare today’s landscape to old photos from the civil war) combined with suburban development has created vast areas of the edge habitat that they prefer. Perhaps the eastward spread of coyotes will put a dent in their population, but until then many suburban gardens will be all-you-can-eat buffets with too many diners.
There are basically three ways to deal with deer: grow plants they don’t like to eat, spray repellents, or fence them out. The internet is full of lists of deer-resistant plants, but in my experience hungry or curious deer will sample anything green, with the possible exception of daffodils. Sprays of bitter or foul tasting substances work well, but they need to be reapplied after heavy rain. If you forget, the deer can destroy a year’s worth of growth in an night. That leaves fences as the only practical, long term solution.
We chose to put up 8′ tall plastic mesh fencing manufactured by Benner’s Gardens. The fence is unobtrusive, particularly during the summer when the leaves are on the trees, and it is easy to put up. Instead of digging post holes, you insert the fence posts into hollow metal spikes that you pound into the ground with a sledgehammer. Only the gate across our driveway required us to dig holes and set the posts in concrete. The fence can actually be put up by a single person, but it is easier with two people: a strong, coordinated person to wield the sledgehammer and a
naive, trusting type brave helper to hold the spike.
The fence would probably fail if a heavy deer leaned up against it and pushed, but deer are creatures of habit, and the idea is to redirect their nightly wandering. So far it seems to be working. We see small herds wandering down the line of the fence in the early morning, but apart from one fawn who found a break in the fence, none have managed to get inside.
Eastern cottontail rabbit (Sylvilagus floridanus)
Unfortunately, plastic mesh is no match for rabbit teeth. Within a few months, the base of our new deer fence was riddled with little holes. Eastern cottontails are basically solitary and do not burrow, so they aren’t as destructive in the garden as a warren of European rabbits. Nevertheless, it is disheartening to find your perennials beheaded and young azaleas gnawed back to stubs.
The solution was to go around the entire perimeter of the deer fence, installing a 3′ metal wire rabbit fence. The bottom of the fence is secured with hooked ground stakes reinforced with heavy concrete blocks at spots where the rabbits try to get in. I see marks where they gnaw on the wire, but they have not succeeded in breaking through.
Pine vole (Microtus pinetorum)
Since they spend most of their time underground, I don’t have a picture of a pine vole, but you can see one here. I first realized that we had a problem when I noticed a recently planted rose swaying more than would seem to be warranted by the light breeze. When I tugged gently on the stem, the entire plant lifted out of the ground, because all of its roots had been eaten off. Then, when I looked more closely, I found the entrance holes of vole burrows all over the garden. Once several more shrubs were eaten and our entire crop of carrots disappeared from the bottom up, we decided to do something about the voles.
I tried trapping them with mouse traps baited with apple placed beside the burrow entrance and covered with a flower pot, but I didn’t catch a single vole. Cats might be effective, but our cats only go outside under close supervision, because I don’t want them killing the local lizards and birds or being killed by an owl or coyote.
What does seem to work is amending the soil when we plant new shrubs and perennials. We mix roughly 1/3 native clay, 1/3 composted cow manure, and 1/3 stalite. Stalite, marketed as Permatill or VoleBloc is a kiln-expanded slate produced here in North Carolina. It basically looks like pumice or dark gray perlite, and I use it as a substitute for perlite to increase drainage and aeration in my potting mix for succulents and tropical bulbs.
In the garden, it serves two purposes. It breaks up the clay, increasing drainage in winter and water penetration in summer, and its rough texture creates an unfriendly environment for the sensitive noses and paws of voles. It really does seem to keep the voles away, at least long enough for the plants to get established. By the time their roots grow out of the amended soil, they seem to be large enough to survive some chewing. I still lose some plants–most recently a Silphium terebinthinaceum reduced to a ring of limp leaves around a vole hole positioned exactly where the taproot used to be–but enough survive so that gardening is an enjoyable hobby rather than an exercise in frustration and gnashing of teeth.