David Wolfe: The Week In Weather

Maple Syrup And Fall Foliage At Risk From Climate Change When you stop by your local farmers market this summer -- at least if you live in a wide swath of the country -- you'll find bottles of locally produced sweet maple syrup. Ask your maple farmer how the weather treated her this winter. Chance are, they'll tell you the wacky undulations from warm to cold was at the very least a headache -- and at most a ruinous condition for their crop. In previous parts of our interview with David Wolfe, the expert on climate change and agriculture explained that wine grapes could benefit from warmer winters, but many fruit and nut trees will suffer. Put maple syrup -- and even the fiery colors of autumn -- in the latter category. The strength and quality of sap is regulated directly by fluctuations in temperature. It is temperature change that dictates the rate and duration of flow, and quality is affected if winter freezes aren't sufficient, or if spring thaws warm too quickly. In other words, the timing of the tap is critical to the quality and abundance of sap and syrup. Unusual winter thaws -- such as the one that occurred through January in much of the country this past winter -- had some farmers tapping trees, and others waiting for true spring. “Once they begin the tapping process, it's usually a six week period of time and you can't break it up,” Wolfe said. “So it's very critical that they decide to do that tapping during peak sap flow.” The issue hints at a larger potential problem: The wholesale northern migration of maples toward a more suitable climate. “It does not bode well for maples in the Northeast,” Wolfe said. “The trend, likely, is that maples will be migrating northward or no longer be found in the region.” And with them would go one of the hallmarks of the fall season -- the brilliant New England hillsides dressed in crimson. This is the third part of a five-part interview with David W. Wolfe, one of four scientists coordinating research into climate-related changes to agriculture as part of the U.S. Global Change Research Program. He is a professor of plant ecology at Cornell University in New York. More Week In Weather Posts Maple Syrup And Fall Foliage At Risk From Climate Change - June 1 David Wolfe: Fewer Fruit And Nut Trees In A Warmer World - May 25 David Wolfe: European Wine Grapes Get Unlikely Boost - May 18 Gavin Schmidt: Wildfires Linked To Global Warming - May 11