Vermont is famous for its maple trees. But for how much longer? Climate change is pushing the North American maple zone gradually but inexorably northwards towards Canada. According to Rupert Cornwell in the Independent, one day soon the maple may be gone.

“Without the maple, Vermont would not be Vermont. Mention the name of this beautiful, quirky and fiercely Democratic sliver of New England wedged against the Canadian border, and maple is probably the first association that comes to mind”.

“A dozen years ago we started hearing from producers they were tapping earlier and making syrup earlier,” says Tim Perkins, director of the University of Vermont’s Proctor Maple Research Centre, probably the world’s pre-eminent seat of learning on the habits of the sugar maple. “So we scoured the records and found that over 40 years, between 1963 and 2003 the opening of the season had moved forward by an average of a week in New England.”

More importantly, the end of the season – when the buds start swelling and maples set about the serious business of producing leaves – now comes 10 days earlier. “So the season now lasts three days less. It doesn’t sound like much. But if you reckon that the season lasts 30 days, we’ve lost 10 per cent of the season in 40 years,” Mr Perkins says.

“Maple syrup production is a very sensitive indicator, depending entirely on freeze and thaw. In a few centuries, the sugar maple may only account for 10 per cent of hardwood trees in Vermont, against 50 per cent today,” Mr Perkins warns. “Some computer models even show it may be wiped out entirely.”