HANCOCK -- With their lines cleaned and hooked up to thousands of tapped maple trees, Berkshire County maple producers are poised for the harvest -- which is set to begin.
Even though the deep winter cold seems to be stretching endlessly, it hasn't really affected the maple sugar harvest yet, maple producers say.
It all depends on the temperatures.
According to Melissa Leab, a partner at Ioka Valley Farms in Hancock and president of the Massachusetts Maple Producers Association (MMPA), what matters most is not how long it stays cold, but rather how quickly the region warms up.
"A slow warm up is better," Leab said. "It all depends on how quickly it warms up and when the trees start to bud."
She noted that daytime temperatures in the 40s and nighttime temperatures in the 20s is the ideal model for a maple harvest.
"That cycle of freezing and thawing is what we're looking for," said Drew Jones, Williams College's manager of Hopkins Memorial Forest in Williamstown. "It's that contraction and expansion that builds up the pressure" that pumps the sap out of the taps and into water lines or buckets, depending on what harvest tactics are being used.
Once the trees start to bud, harvest time is pretty much over.
At Hopkins Forest, the maple harvest is conducted by students as a learning experience. They have a relatively small number of trees tapped, so they still use buckets under the taps to catch the sap.
More modern operations with thousands of trees attach lines to the taps, which carry the sap to collection tanks. The sap is transported to the sugar house, where it is boiled down until it reaches the consistency of maple syrup.
The extended cold weather, said both Leab and Jones, should not hurt the harvest. The hard part comes if the weather warms up and stays warm, even overnight. Or if a warm spell is followed by a cold snap for a few days, keeping the sap frozen in the tree. Either event would reduce the harvest and affect the taps in the trees, which also results in a smaller harvest.
The cold weather has delayed the start of the maple season, but with the warmer weather this weeked some maple producers may have already started.
"If this weather breaks soon we could be in for some big days," Jones said on Friday.
"By Saturday, we could be in for some good flow," agreed Leab.
Meanwhile, special events around New England are coming up to mark the start of maple season.
Hopkins Memorial Forest will celebrate the season on Saturday, March 15, from 11 a.m. to 2 p.m. MapleFest -- which highlights the Yankee tradition of tapping local maple trees -- will offer visitors the opportunity to take part in the process from the tree to bottle.
Leab and the MMPA hosted a special event to tap the ceremonial first maple tree in Belchertown Friday, where Gov. Deval Patrick read a state proclamation declaring March to be "Maple Month" in Massachusetts.
By the end of next week, more than 300 Massachusetts maple producers will have started the harvest and production cycle. This year's maple season will be highlighted by Maple Weekend, March 22-23, when sugarhouses around the state will be open to visitors. Lists of participating sugarhouses and restaurants are available at www.massmaple.org.
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