How climate change affects the sugar maple.
On the second and third weekends of March, more than 50,000 visitors will celebrate the 55th annual Highland Maple Festival in Monterey, Virginia. It is one of the southernmost sites for maple sugaring in the United States, and because of that, the festival may not be around in another 50 or so years.
The reason? Maintaining a good supply of maple syrup relies on precise climate conditions of freezing night temperatures and warm spring days. But scientists at the University of Vermont and elsewhere believe global warming may be affecting this ancient native food source in the United States by shortening the season, pushing it earlier and moving it northward.
In testimony before Congress in 2007, Timothy D. Perkins, Ph.D., director of the university’s Proctor Maple Research Center, said the season now begins about 8 days earlier than it did 40 years ago and ends about 11 days earlier.
Extreme weather, particularly warmer summers and drought conditions, also contributes to the decline in syrup production. According to an assessment of the New England region conducted by the U.S. Global Change Research Program, temperatures in maple-sugar production areas have increased steadily since 1916, a serious problem since sugar maples cannot thrive if summer temperatures are consistently above 77°F. This could be a boon for Canada’s maple industry, however, as sugar-maple forests migrate north.
The likely outcome, says Brian F. Chabot, Ph.D., professor of ecology and evolutionary biology at Cornell University, is that maple-syrup production in the United States will move earlier and earlier over the next 100 years.