Emerald Ash Borers Kill National Lakeshore Ash Trees
Emerald ash borer discovered in Sleeping Bear Dunes National Lakeshore
News Release Date:
September 12, 2011
In mid-June, Sleeping Bear Dunes National Lakeshore (National Lakeshore) staff identified an ash tree near Little Glen Lake infested with Emerald Ash Borer (EAB).This was the first time EAB had been confirmed within the National Lakeshore. National Lakeshore staff is working with partners and visitors to assess and mitigate the damage caused by these invasive pests.
Since the initial EAB discovery, National Lakeshore staff have been working with the Michigan Department of Agriculture to assess its spread. It appears that up to 90% of the ash trees on the mainland in the National Lakeshore may be infested. With the rapid rate at which the spread has occurred, all of the ash trees on the mainland in the National Lakeshore are at imminent risk. The highest level of known infestation occurs at the north end of the park in the Good Harbor area.
EAB was first discovered in the U.S. in Detroit in 2002; however, it is thought to have been introduced in the early 1990s in wooden packing material that originated in Asia. Since its discovery in Detroit, EAB has been found in 13 states. Although the insects are only able to travel about one mile per year on their own, EAB has spread far more rapidly through transport of firewood. It is estimated that 80% of the infestations in Michigan are the result of firewood transport.
Superintendent Dusty Shultz notes, "The National Lakeshore is saddened by the news that this destructive insect has been found here. We are in the process of working with other agencies to explore our options for control, but the outlook for the ash trees is bleak." EAB kills all species of ash (Fraxinus spp.) found in Michigan by feeding on the cambium layer that transports nutrients in the tree. The feeding effectively girdles the tree, restricting nutrient transport and eventually killing the tree.
In addition to EAB, area forests are threatened by numerous other pests, including Asian longhorn beetles (affecting maples), beech bark disease, oak wilt, and hemlock woolly adelgid. In an effort to slow or prevent the spread of forest pests, the National Lakeshore instituted a partial firewood transport ban in its campgrounds in 2011, and plans to expand that to a full ban in 2012. All firewood used in the campgrounds would have to be purchased onsite from the National Lakeshore's approved vendors, or collected by camping permit holders as dead and down wood within designated areas of the National Lakeshore. EAB may be here to stay, but visitors can help stop the spread of other invasive pests by not moving firewood.