Junk Science: Mother Nature and Maple Syrup

Published May 1, 2005

In the spring of 2004, the Boston Globe and Associated Press created a sensation by reporting that global and regional warming are affecting maple syrup production and will eventually spell disaster for maple syrup farmers. The Globe‘s report was based largely on anecdotal reporting of people’s memories.

First, read the Globe article, reproduced below. Then look at actual temperature readings from Vermont weather stations. Finally, read a March 2005 article from Albany’s WNYT-TV Web site, reproduced below, contradicting much of the Globe‘s claims. Is global and regional warming really spelling doom for Vermont maple syrup production? You be the judge.
James M. Taylor

FICTION: Warming Trend Blamed for Syrup Season Change
By Associated Press, 3/22/2004

ACWORTH, N.H.–The state’s maple syrup producers say they can see the effects of global warming in their backyards: They are tapping their trees about a month earlier than their ancestors did.

A giant chart on the wall of the Clark Sugar House in Acworth shows the maple syrup season began changing about 20 years ago.

Since 1896, generations of Clarks attached their buckets in March, and almost never made syrup before then. But in the mid-1980s, they began tapping mostly in February, and March became the month for boiling and bottling.

Annual 1

“Most everybody’s tapping a lot earlier than they used to,” said Arvin Clark, 72, who has been running syrup production at the farm since 1959.

The Clarks’s chart might just be a glimpse of the future. Scientists around the world, including some at the University of New Hampshire, predict that by 2050 New England’s average temperature will rise between 6 degrees and 10 degrees. That warming will vastly alter the climate needed to support a northern hardwood forest, including sugar maples.

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A delicate balance of sun, rain, snowfall, and freezing temperatures is what helps the tree turn its starch into sugar. For the sap to run, nights need to be below freezing, ideally in the mid-20s. Days need to be in the mid-40s.

For now, the warming trend has changed the ideal dates for tapping. But eventually, some specialists say, it will reduce sap production and leave the trees more vulnerable to insects and disease.

The trees could spread north as the freeze-thaw cycle becomes more unpredictable and the seasons start and end earlier. Those that remain will produce less syrup of lower quality.

That’s bad news for New Hampshire’s maple syrup manufacturers, who annually pump $4 million into the state’s economy.

“I think the sugar maple industry is on its way out,” UNH researcher Barrett Rock said in 2002. Rock led major research on the risks associated with global climate change.

Tim Perkins, director of the Proctor Maple Research Center at the University of Vermont, is doing research on whether climate change has affected the amount of sap producers can expect from their trees. He declined to preview his results, but agreed that climate change will hurt syrup production in New England. This year, production is generally good because last year’s weather conditions were just right. But a spell of unseasonably warm weather earlier this month hurt sap production and quality, said Bill Eva, president of the Maple Producers Association.

FACT: Cold Weather Slows Maple Syrup Production
Sugaring season getting off to slow start
March 15, 2005

USA–If you’re tired of these winter temperatures, you’re not the only one. This month’s below freezing nights and cold days means conditions for maple sugaring are less than ideal. Producers worry this could be the smallest syrup harvest in decades. Robert Leab’s trees are tapped. But four weeks into the sugaring season and this is just Ioka Farm’s second syrup run of the year.

“It’s usually the end of February when we start and here it is the middle of March and we’re just getting going,” Leab said.

Early last week, Leab managed 45 gallons of the sweet stuff and is hoping this week’s more mild temperatures will move him closer to the 850-gallon total that represents 30 percent of the farm’s income.

“We had more snow in March than all winter long. We had spring in January and winter finally caught up with us,” Leab observed.

Ideal sugaring conditions are 25 degrees at night and 40 degrees during the day. It’s been a lot colder overnight and not even close to 40 during the day.

“It’s not perfect conditions. But I don’t see it hurting too much of the industry. If anything we’ll see an increase in prices and that’s what happens with such a specialty agricultural area,” explained Berkshire Grown Executive Director Danielle Mullen.

Not just a syrup producer, Leab knows all too well that agriculture depends on the charity of Mother Nature.

“There’s not much you can do. She’s going to determine what happens. There’s things you can do to control it. So [we] just set … all the scenarios the best we can and hope for the best,” Leab said.

Leab is literally going with the flow.