SHELBURNE FALLS, Mass.—Sealing up the tanks makes for cleaner sap.

Hunter Sessions, 22, and father Criag Sessions of Winston’s Sugar House in Shelburne Falls, Mass. have sealed up thier sap collection tanks airtight.

“You try to keep the sap as clean as you can before you process it,” Craig Sessions said.

“You don't want it filling up with rainwater or any other contaminants in there.”  

Hunter said the less particles or dirt in the tank, the better it is for the RO membranes.  

"It won’t clog up the RO and the pre filters will last longer,” Hunter said.

Sides are siliconed shut and bungee cords secure the lids.

"We also wash every tank after every boil,” Craig Sessions said.