White-tailed deer are present in every Michigan county. They make use of a wide range of habitats, and are prolific reproducers - a healthy herd grows an average of 20 to 30 percent each year. More than 75 percent of Michigan's deer population lives on private lands, and as their numbers increase and food becomes scarce, hungry deer forage closer to our homes and browse on our plants.

Some Methods for Controlling Deer Damage

1)Use plant species that deer do not favor in your home landscaping - deer will only browse on undesirable plants under extreme conditions. For a list of such species, view the PDF file at this website:
http://www1.uwex.edu/ces/pubs/pdf/A3727.PDF

2) Fencing/ Barriers

For smaller areas, a visual barrier can be made of light fabric or plastic materials (burlap, woven cotton, plastic sheets, etc.) at least 6í high. Weigh it down and make sure there aren't any gaps where deer could look through.

Small areas or individual plants are best protected by mesh wire fencing. Recommended mesh size is 2" X 4" or smaller; smaller mesh will also keep rodent pests out. The encircling wire must be at least 5í high.

Fencing can also be placed over plants to protect them. This works well for gardens that are small and low to the ground. String binder twine in a horizontal grid approximately 12" above the area you wish to protect ñ deer will be reluctant to jump over or step down through the fencing to reach the plants.

Electric fencing is another option for areas of 40 acres or less. Such fencing can range from expensive permanent, high-tensile fences for highly valued crops, to temporary fences or plastic polytape electric fences (the plastic attracts deer to "investigate" and delivers a shock upon contact).

3)Repellents
There are two kinds of repellents: 1)contact, which are applied to plants and repel deer with their taste; and 2)area, which protect an area by repelling deer with their odor. Some repellents are commercial and can be found where agricultural products are sold; some, such as strong-smelling soaps and bags of human hair, can be made at home. It is important to recognize, however, that repellents can lose effectiveness and be a time-intensive method.

4)Invisible Fence and Dogs
Keeping dogs enclosed within an invisible electric fence is another way to prevent deer from entering your yard. Not all dogs are created equal, however, when it comes to deterring deer; the most effective are males of a "herding" breed such as border collies, and two males work better than one.

more info: http://www.ext.colostate.edu/pubs/natres/06520.html