Too Many Deer?

Person in snowy woods affixing strips of colored material to wire fencing so animals can see it and won't be harmed

Looking into the impact of the deer population on a Woodstock forest

By Jack Minich, VHCB AmeriCorps Land Management Coordinator

On a cold December morning, I drove with Pieter van Loon, VLT forester, to a high pasture above the King Farm—a historic farm VLT owns in Woodstock. In the side mirror, I eyed the green fence posts threatening to spill out over the tailgate as we climbed the rough track. After arriving at the hilltop, we began hauling the fencing materials—posts, chicken wire, flagging, and stakes—into the sugar maple stand where we were to build a deer exclosure.

Deer exclosures are fences that keep deer out. Gardeners have long used them to prevent deer from devouring the season’s harvest. However, they can also show how too many deer prevent new trees from growing in our woods. This over-consumption reduces the survival rate of tree saplings, which are typically preferred by, and in reach of, hungry deer. Put simply, this “overbrowsing” inhibits forests’ ability to regenerate in a healthy way.

Overbrowse in the maple stand at King Farm has resulted in a park-like view in the woods: tall, mature sugar maples tower above, but the next generation of trees resemble bonsai plants. Deer nibble and strip the buds, forcing the young trees to grow oddly and remain stunted and close to the ground.

Raising the alarm about deer overbrowsing our woods is difficult though, as people need to see its impact. The fence we built that cold winter day is an attempt to do this.

fenced area with trees and shrubs growing on one side, no shrubs on the other

Exclosures, like this one at Valley Forge National Historical Park, Pennsylvania, can show how too many deer prevent new trees from growing in our woods.

In a few growing seasons, we expect that the little trees will have matured and grown, in stark contrast to the woods outside the 100-square-meter area. This exclosure will become one of many, as a grant from the US Forest Service is supporting a partnership between VLT, the Department of Forests, Parks and Recreation, and UVM Extension to build exclosures on community forests across Vermont.

At the King Farm, the exclosure went up relatively easily, despite temporarily losing tools in the snow. Adorned with bits of flagging to make the chicken wire visible to deer and other animals, the exclosure isn’t pretty, but it serves a purpose. In addition to raising awareness, it will help us gather data on plant growth that will support a statewide effort to look at this important issue. We look forward to reporting the results back to our members.