New study shows relationship between deer and timber growth in U.P.

Hardwood forests and deer are some of the traditional hallmarks of the Upper Peninsula, but they exist in balance with each other, and a new study has explored that relationship.

The Center for Systems Integration and Sustainability at Michigan State University has documented sugar maple saplings and deer populations in a few locations in the U.P. and determined the hardwood forests are not regenerating as foresters would hope, because young deer are eating them before they have a chance to grow.

Sugar maples are among the trees often counted upon to fill in the gaps left by selective logging, which is practiced in many parts of the U.P. as part of the modern timber industry.

But the maples aren't growing as expected, instead being eaten by deer, according to researchers. Megan Matonis, one such researcher, says that may not mean good things for logging in the long run.

"We've found that deer, light availability, and competition from non-tree plant species are affecting sugar maple regeneration in parts of the Upper Peninsula," says Matonis. "No sugar maples are regenerating in the southern area near Escanaba. In the future, this could challenge the sustainability of timber harvesting in this region."

The researchers spent two years studying U.P. forests where hardwoods were cut, looking at 3,000 square miles of both public and private land ranging from Crystal Falls to Escanaba to Marquette.

They found in areas where deer population was highest, regeneration of cut hardwoods was poor, and tending toward less sustainable. They also studied the amount of light in gaps left by logging, competition from other plants, seed supply, and soil quality to determine how these affected regeneration.

The finding included that sugar maple saplings were found to be thriving in northern U.P. forests, where heavy snows force deer to move to the southern U.P. for the winter in search of food, but in the southern forests, almost no saplings survived, instead being eaten by deer.

The study, titled "Gap-, stand- and landscape-scale factors contribute to poor sugar maple regeneration after timber harvest," was published in the journal Forest Ecology and Management.

Writer: Sam Eggleston
Source: Megan Matonis, Center for Systems Integration and Sustainability