Deer hunting season is upon us, and so it seems appropriate to do an article about deer damage to landscape plants. Fall and winter are a time when deer can cause significant damage to landscape plants. Two types of damage can occur: antler rubbing and browsing.
Antler rubbing is done by males during the mating season. They do this in the fall to remove the soft velvet covering and to strengthen their back and shoulder muscles. Rubbing damage will tear the bark off small trees. If the bark is stripped all the way around the tree, it can girdle and kill the tree. If the damage is only part way around the tree, the tree should recover. Clean up any loose bark by trimming it back to solid bark material. Do not apply pruning paints. Just let the plant heal naturally.
Browsing, or feeding, occurs during the winter and can be especially severe in winter with long-lasting snow cover. Deer feed on a wide variety of plants, including fruits, buds, flowers, and small stems. Like us, they have favorite foods, but when food is limited, they'll eat just about any plant.
Damage can be over six feet above ground level. Deer browsing is one of the primary plant damage concerns in both natural and residential areas. Since the average deer eats 6 to 8 pounds a day, they can cause significant injury or death to landscape plants.
What can be done? Deer like woodland edges. One way to lessen the potential for damage is to have as much open area between woodland edges and landscape plants as possible.
Another option is to put in plants deer don't like to eat. This includes plants such as boxwood, birch, and Colorado blue spruce. Other plants that are seldom severely damaged include honey locust, red osier dogwood, and Norway spruce. Extension Educator in Horticulture, Martha Smith, put together a fact sheet on plant material resistant to deer. For a copy go to web.extension.illinois.edu/fmpt/hort.html and scroll to the bottom of the page.
Repellents may help in small areas. They will not eliminate damage but may reduce it. They work in two ways. A contact repellent makes the plants taste bad, while area repellents make the area smell bad. Repellents should be applied by mid-fall to early winter. Reapplications are usually needed to extend the effectiveness of the product.
There are many types of fencing that successfully protect plants from deer damage. Wire or plastic mesh, electrified fence (vertical or slanted), and poly wire options are available, based on deer pressure and the amount of protection desired.
For more information on deer and other wildlife problems, go to the University of Illinois Extension website "Living with Wildlife in Illinois" at http://web.extension.illinois.edu/wildlife.