Jennifer Schultz Nelson
Extension Educator, Horticulture
I grew up as a kid that loved all the wildlife that wandered into our yard. As an adult homeowner with a relatively new landscape in a new subdivision, I feel like this year I've declared war on the local wildlife while trying to defend my tender young plants.
I've been in my home for four years and apparently that's how long it's taken the local deer population to find my yard and unleash their destructive power. I think the local rabbits probably told them the Nelson's garden is particularly tasty. Rabbits have been a serious problem at our house for the last two years.
The last week has been very sad in the Nelson garden. My husband planted forty ornamental sweet potato vines along an area in the back half of our property, and they were gorgeous. One evening last week we were outside and talked about how we should take a picture of the planting beds that included the sweet potato vines. The next morning I walked outside and noticed that every single one of the plants was eaten. Not down to the ground, but all that was left was a few sprouts that could survive if they weren't cruelly attacked further.
A little sleuthing revealed the identity of the attacker. For one, unless an angry mob of rabbits converged on our yard, the shear volume of plants devoured in one night suggested larger animals-- probably deer-- were the culprit.
The damage on the plants was also a dead giveaway as to the guilty mammals. Rabbit damage looks like someone went crazy with pruners, each branch or shoot cut cleanly at a forty-five degree angle by their powerful incisors. I have actually accused my husband of overpruning shrubs, when in fact it was rabbit damage!
Deer on the other hand, lack upper front incisors and so grab and pull at vegetation they want to eat. The ends of remaining branches and shoots are jagged and if they are small enough, plants may be totally pulled out of the ground. Deer also only eat what they can reach, which is only about eight feet high. The stems of the remaining sweet potato vines had jagged edges-- clearly the deer had an all-you-can eat buffet in our yard.
Other clues which may be helpful are tracks—deer have hooves cloven into two halves, rabbits have distinct pairs of tracks for the front and hind feet respectively. Rabbits will often construct grass lined areas called "forms" to offer some protection on the ground.
Deer and rabbit damage is most noticeable in the spring and early summer before much plant growth begins. Usually deer and rabbit damage to landscape plants is worse in years with colder winters and more snow cover as other nearby food sources run out.
In managing deer and rabbit damage, homeowners need to do their homework. There are plants that both deer and rabbit absolutely love, and there are plants that they will only eat if it is the last green plant available. Generally speaking, both deer and rabbits will avoid any plant that has a lot of sap or a lot of scent. There are many plant lists available in books and online listing plants resistant to feeding by deer or rabbits or both. Of course, there are exceptions. Sometimes even a plant touted as something deer would never eat will sometimes get eaten in the right circumstances. Nature is seldom absolute.
Using scent or taste repellents for deer and rabbits is usually a viable option for homeowners. Realize though that they may need to be reapplied after rain or extended periods of time. They are most effective if applied before damage has occurred. Also, it is a good idea to rotate among several different repellents to minimize the chance that the animals will get used to a particular scent or taste. I can attest to the fact that many commercially available repellents smell absolutely horrible, and one shouldn't stand downwind while applying said products.
Another less noxious option is hanging bars of strongly scented soap near the plants that deer seem to love. We combined this with the spray on scent repellents on the sweet potato vines, figuring that might help get our message across more effectively, at least for the time being.
In many cases excluding deer and rabbit with fencing is another good option. Electric fencing to deter deer is recommended in extreme cases, but is not an option for most people in suburban areas. Though deer can jump twelve feet high, eight foot high fences are generally enough. If the area being fenced off is less than about fifteen feet wide, six foot high fences are adequate. This is because deer have poor depth perception, and are hesitant to jump into places that they perceive might be too narrow. Another way to take advantage of this is to place two shorter fences a few feet apart. Unable to judge the distance over both fences, often deer will avoid the area.
Rabbit fencing only needs to be about two feet high, and have a few inches buried under the soil to prevent rabbits from digging under the fence. Remember the openings in the fence materials should not be big enough for the rabbits to fit through!
In a lot of cases it can be difficult if not impossible to prevent all damage from deer and rabbits. Some damage is inevitable in many locations. In these cases it may be helpful for homeowners to work on tolerating at least some damage to their landscape.