Michigan’s Enormous Forest Regeneration Study in Heavy Deer Population

MADISON, Wis. -- In a search to find ways to improve forest regeneration odds amidst a heavy deer browse, Michigan is hosting a study on 140 sites covering nearly 4,000 acres. And the most sites are in the Upper Peninsula, where there will be likely clues for northern Wisconsin.

The study will test three management methods to get as many trees as possible to the “recruitment” stage. A stand reaches the recruitments when young trees become saplings (above the reach of deer). “Large portions of Michigan forests have experienced decades of recruitment failure mostly due to intense browsing pressure by deer”, according to the organizations conducting the study.

The work is being done by Michigan State University in cooperation with the Michigan DNR and support from the forest products industry and Safari Club International, Michigan Involvement Committee. The researchers involved in the study believe that it is one of the largest studies ever conducted of alternative forestry prescriptions to reduce deer browse after a harvest.

Thirteen counties in the UP have sites in the research project. The forest is predominantly northern hardwood with sugar maple as the dominant species.

The three (2019) harvest scenarios being tested are:

• Use of large gaps (0.3 to 1 acre), larger than typically employed (a gap is an area left without trees after a harvest to allow more sunlights and water to boost remaining tree growth)
• Shelter wood (overstory reduction to 40-50 percent)
• Seed tree (harvest all but 6-8 high quality trees per acre)

Gary Roloff of the Applied Forest and Wildlife Ecology Lab at MSU said that it normally takes about 10 years to show recruitment. He said that in areas where tops will be left some early results are likely to be evident in four growing seasons.

An alternate prescription involves soil scarification and herbicide application, Roloff said. Those sites will take longer as they are being treated this summer. It is hoped that that technique will improve germination and improve the species mix.

It is hoped that the research will demonstrate methods that produce the best outcomes in terms of robust early forest generation of a desirable species mix.