Deer exclusion fencing on Michigan farms
Protecting high-value crops from deer depredation is tricky (and expensive) business.
Accurately assessing crop loss to whitetail deer feeding is a challenging task. In legume and grass forage crops, deer damage is not always obvious and losses to deer feeding may be attributed to other causes. Deer feeding in corn, beans and other row crops is easier to identify and quantify, but just as difficult to manage.
In the late 1980s, a series of trials were conducted by MSU Extension staff in Presque Isle County to assess yield loss in alfalfa and dry beans due to deer feeding. In dry beans, 130 deer exclusion “cages” with dimensions of 3 feet wide x 5 feet long x 2 feet high were placed on four sites. For each harvest sample collected from under a cage, two samples were collected from sites not protected from deer. Data indicated that yield losses attributable to deer feeding ranged from 24 to 43 percent. Several factors that contributed to the problem were: The presence of large amounts of wooded cover during the entire year; a series of favorable winters which resulted in a large overwintering deer population; and availability and accessibility to agricultural crops as a feed alternative.
A similar study on alfalfa in a high deer population situation in Hawks suggested that 18.7 percent of the potential alfalfa yield in the field studied was removed by deer feeding at a critical growth stage in the annual plant cycle, when the plants were drawing heavily on root reserves to begin growth.
Farmers concerned about crop losses to deer feeding remain high in many areas in Michigan. Long-standing tensions exist with innumerable variations between agricultural and deer-hunting interest groups. State wildlife management professionals attempt to find a reasonable balance between the conflicting demands of farmers and deer hunters. Crop damage permits and block permits are tools that have been used to reduce deer feeding pressure on some farms. Go to the Michigan Department of Natural Resources website for information on block permits and crop damage permits in Michigan.
Of course, neither farmers nor deer hunters are fully satisfied with the results very often. Michigan State University’s Department of Fisheries and Wildlife conducted a study comparing attitudes of farmers versus deer hunters with regard to controlling crop damage. Results of the study can be found by reading A Comparison of Deer Hunter and Farmer Attitudes about Crop Damage Abatement in Michigan: Messages for Hunters, Farmers and Managers.
Where crop value justifies the expense, deer exclusion fencing is worth consideration. Many technical resources from the public and private sectors are available that describe the construction and effectiveness of deer fencing, including Deer from Ingham County MSU Extension, and a chapter on deer control in the Internet Center for Wildlife Damage Management.
A 1994 study of farmer’s deer exclusion efforts in Michigan’s Upper Peninsula and northern Lower Peninsula and northeast Wisconsin revealed the following.
- High tensile electric was the most commonly used type of deer exclusion fence with 6-foot height striking a good balance between effectiveness, cost and ease of installation.
- Eight-foot woven wire was perceived as most effective by fence users. However, the high cost of installation limited its widespread use.
- Other types of fence with inconsistent or low ratings by users were high-tensile non-electric and one-wire or two-wire temporary electric fencing.
- All non-fencing control alternatives were perceived as relatively ineffective based on farmer perception, with the exception of state-issued block and crop damage permits and regular hunting.
For more information on the deer exclusion fencing study, contact MSU Extension crop production Educator Jim Isleib at 906-387-2530.