Along the northeastern edge of Kettle Hole Marsh sits half of a forest. An overstory of red oaks andboxelders towers above a messy tangle of stumps and bare ground. The area feels gutted, the space where an understory should be strangely empty. A little more to the east, right where the arboretum meets Canada Avenue, there is a long stretch of downed trees and shrubs, stacked about six feet high.
This is all part of one of the arboretum’s largest invasive species removal projects. Not too long ago, the forest surrounding Kettle Hole Marsh was filled with dense thickets of common buckthorn (Rhamnus cathartica), an invasive shrub brought to the United States from Europe in the 1800s. Originally used as a windbreak in hedgerows and along roadways, buckthorn quickly and aggressively spread throughout the continental United States.
Buckthorn is a merciless competitor. Their leaves come early and leave late, allowing them to monopolize on an extended growing season. They grow in dense clumps, reproducing rampantly and shading out any seedling trying to sprout from the forest floor. Instead of a biologically rich understory, infested are covered in a thick buckthorn carpet. This wreaks havoc on native ecosystems.
At Kettle Hole, the removal process began a few months ago. Forestry mowers cut buckthorn to the ground, leaving trails of shredded stumps and scattered branches. Exposed stumps received an herbicide treatment to prevent regrowth. What would have taken years to manage by hand took only a month to complete with machinery. The ground is now bare, ready for new seedlings to take root.
While the stripped ground east of Kettle Hole may seem like destruction at first glance, it is actually an important first step in restoration.