The maple syrup business in Vermont is booming as a result of increased production and investments from out-of-state firms. Sweet Tree Holdings, the largest single-source maple operation in the world, was formed in 2013. Owned by Montréal-based Fiera Comox, Sweet Tree produces value-added maple products under the Maple Guild brand. At its massive Island Pond factory, more than 100 employees use four stainless-steel evaporators to process sap from almost half a million Essex County trees, generating about 6,000 gallons of syrup per hour.