Mule Deer - Red Butte Garden

Mule Deer

Gardening Information

By Crystal Kim, Red Butte Garden Horticulturist

Mule Deer (Odocoileus hemionus) are a common sight in our mountains and foothills, and increasingly in many neighborhoods and yards. Deer are the most influential non-domesticated grazer in our region. Their habit of grazing some grasses to the ground creates more diversity in the plant community by providing opportunities for other grasses, flowers or tree seedlings to take root. Their tip grazing also provides natural pruning that keeps plants compact. Though they are an important part of our local ecosystem, when we encounter them in our own yards, their appetite for garden plants becomes a challenge. While there are no perfect solutions for keeping deer from munching your garden, there are strategies that can help deter deer and minimize plant damage.

Mule deer are migratory, depending on the season and food supply. They spend much of the summer in higher mountainous areas and move to lower elevations in the winter to avoid deep snow. This means that they are most likely to feed in human landscapes from December to April, depending on location. Homes located in the foothills, inside natural migratory ranges, can expect more damage. However, some deer stay in lower elevations during the summer rather than migrating back to higher elevations, increasing the potential for garden damage year-round.

Damage Characteristics

Deer-damage to plants can sometimes be difficult to identify. One key characteristic is a jagged edge or torn surface on twigs or stems. Deer have no upper teeth, so they rip food rather than cut it in clean lines. They are browsers, nibbling on a variety of plants, rather than consuming whole plants. Young plants may be uprooted as deer attempt to tear off the tips. They are surprisingly adept at removing flowers while leaving the rest of the plant alone, even on prickly plants such as roses.

Plant Selection

Just like humans, deer have a preferred palate of food they like to eat. The first strategy for minimizing deer damage is to limit the plants in your landscape to those that deer do not prefer. Although deer will eat almost anything if hungry enough, there are plants that they favor and others that they generally do not eat. How much a deer feeds on a certain plant is based on a combination of its palatability and whether alternate food sources are available. Of the plants that deer prefer, some are worth considering because of their tolerance to deer browsing. If you don’t want to make big changes in your existing plantings, a border of unpalatable plants around the perimeter of your garden may discourage deer from coming in.

See a list of deer resistant plants.

Barriers

After proper plant selection, the next strategy to consider is preventing access to your yard, whether by constructing a barrier around your garden or by protecting individual plants. Fences should be installed before deer make a habit of feeding in your garden, as deer are harder to deter once they’ve established feeding patterns. Fences should be sufficiently tall to prevent deer from jumping over them. A fence 6 to 8 feet tall will keep some deer out but is still capable of being jumped over. For more complete exclusion, 10 to 12 feet is better.

Fencing can either be solid, such as a privacy fence, or made of wire or mesh. The advantage of a solid fence is that deer can’t see through it, and therefore are less likely to jump if they don’t know what’s on the other side. A less expensive fence can be made of commercial heavyweight deer netting if deer pressure is low to moderate. Deer netting is easier to work with than wire mesh and blends better into the landscape. Additionally, a very simple and inexpensive fence can be created by stringing single strands of monofilament twine (such as fishing line) between posts. Strands should be spaced 6” apart, or farther if deer pressure is low. Deer bump into the line, and because they can’t see it, are spooked and turn away.

Individual plants can be protected with tree shelters, wire cages, plastic bird netting and burlap. These options are less attractive but may be desirable if you don’t want to fence your whole yard. Tree shelters protects bark from being stripped by antler rubbing in the fall, while wire cages can prevent browsing as well as antler rubbing. Wire cages should be 4 feet tall and 1 to 1.5 feet in diameter. Bird netting can be used to provide temporary protection of fruits, berries and flowers if deer pressure is low. Burlap wrapping can be used to prevent winter browsing of soft evergreens, with the added benefit of preventing limb breakage from snow load. **

Scare Tactics

Deer are easily startled, but not easily fooled. Motion activated sprinklers, lights or noises are great at getting deer’s attention, but usually don’t scare them off completely. Deer will get used to and start ignoring deterrents that they realize don’t pose any actual threat.

Repellants

Repellants are another possible resource for discouraging deer browsing. However, many are unreliable and may even be ignored by a hungry deer. They can only be applied when temperatures are above freezing and must be reapplied periodically, usually every four to five weeks or after rain. The most effective repellants are those that contain eggs, especially putrid eggs.

You can also make your own egg-based repellant with this recipe: http://forestry.usu.edu/files/utah-forest-facts/preventing-deer-damage-to-your-trees-and-shrubs.pdf