University of Vermont

New Maple Tubing Research Benefits Small-Scale Sugarmakers

Maple sap running through tubing at the Proctor Maple Research Center.

Art Krueger likes to tinker. An engineer by profession, his ability to adapt or develop just about anything he needs allows him to live completely off the grid in Shrewsbury.

He and his wife, Trish Norton, own Krueger-Norton Sugarhouse, selling syrup, fudge and other maple products. Although most of their electricity comes from a combination of solar panels, wind generator and micro-hydro turbine, for the sugaring operation, Krueger rigged an old pickup truck to run the generator for his vacuum pump system.

So when he heard that Tim Wilmot, University of Vermont (UVM) Extension maple specialist, had designed a tubing system using natural gravity instead of mechanical pumps, he was intrigued. The fact that the maple expert was getting sap yields equivalent to that of a traditional vacuum pump system in his research trials at the UVM Proctor Maple Center in Underhill just sweetened his interest.

The system uses smaller diameter tubing--3/16-inch instead of the traditional 5/16-inch--to create a higher vacuum with gravity flow. For maple producers who can't afford to invest in costly equipment, have areas without access to electricity for fueling the pump or even prefer to live off the utility grid like Krueger, the new technology is a cost-effective option with the potential for high sap yield--and higher profits.

"It's the greatest thing since sliced bread," Krueger exclaims. He tried the new technology with 200 taps in 2012 and was so pleased with the results that he applied for a Vermont Working Lands Enterprise Initiative grant to convert his entire 3,000-tap sugarbush.

"Not only is this an energy saver, but we are using less material and lighter tubing that is easier to carry when installing." He developed his own tubing wheel for laying out pipeline in his woods as well as found ways to adapt standard industry fittings to the smaller-diameter tubing, information he's shared with Wilmot and other producers.

Andy Hutchison, a Leicester sugarmaker, first heard about Wilmot's research at the UVM Extension Maple School in Middlebury in 2012.

"I did not go hear Tim speak," he admits, "but my wife went and thought it was interesting. I later read about his research in Maple Digest. What he wrote made sense, but it sounded too good to be true.

"I sell sugaring equipment and like to make sure what we sell works before I promote it," says Hutchison, who owns Mount Pleasant Sugarworks with his wife, Donna. He decided to test the system on a small section of his 3,500-tap sugarbush where he did not use vacuum pumps, an area adjacent to his driveway where customers could easily check it out for themselves. 

"My experience with 125 taps showed that production and vacuum levels were similar to Tim's.  I ended up having to buy a larger tank for this bush. The one that was adequate for years was no longer large enough to hold a day's sap flow."

Steven Roberge, University of New Hampshire Cooperative Extension forester, invited Wilmot to speak at the New Hampshire Maple School in Tilton, N.H. last October and has seen interest from sugarmakers in his state, especially small producers who may not have the cash flow to cover and recoup the costs of putting in a vacuum system.

"Lots of advancements like reverse osmosis are equipment-heavy," he points out, "and are usually adopted by large producers with 10,000 taps or more. Smaller producers get left behind. Tim's research has the huge potential to increase a sugarmaker's production by 50 or even 100 percent.

"For a small producer making 150 to 200 gallons of syrup per year, even if production increases by one third using this technology, that's a pretty large jump. It may allow folks with a marginal run of sap to stay in the game. Any time we can increase sap production and maintain costs, that's great for the industry."