CHARLESTON – The Niles family, enveloped Sunday afternoon in a fog of maple syrup steam, is looking forward to an excellent sap season. “Compared to last year,” said Michael Niles, 28, “we are way ahead.”

Maine Maple Sunday was held this weekend, and more than 40 producers opened their sugarhouse doors, sharing the process for turning bitter maple sap into the smoky, seasonal taste.

Maine is the nation’s second-largest maple syrup producer behind Vermont, with production exploding from less than 12,000 gallons a year through most of the 1980s to 230,000 gallons last year.

Although Maine boasts about 300 producers statewide, most of the state’s syrup is made by about 50 producers in the northern reaches of Somerset County.

What started out as a family hobby has become big business for the Niles family of Charleston, who market their maple syrup, fudge, candy and cream throughout central Maine as G&M Maple Products.

“We started out just boiling sap on the kitchen stove,” Michael Niles said. “The steam peeled the wallpaper.”

Today, the family leases trees in Charleston and Exeter and has increased the number of taps they put in this year to 1,300.

“We are about 105 gallons of syrup ahead of last year,” said Niles. “It’s supposed to get cold tonight, and that means we’ll have more sap tomorrow.”

Ideally, daytime temperatures should be about 40 degrees with nights remaining freezing. This cycle causes sap to move up and down the tree and allows for optimum tapping. If cold temperatures turn warm too quickly, however, sugar maples start to bud and their sap turns bitter.

“We are supposed to have cold nights most of the week, and that will keep the sap running,” Niles said.

Surrounded by the steam from the evaporator, Niles explained the process this weekend to dozens of visitors on Maine Maple Sunday, which is held on the fourth Sunday of March each year.

While Gary and Michael Niles were busy in the evaporator room, the women of the family, Claudia and Rachel Niles, were out front in the store boxing up maple fudge and candy and selling dozens of jugs of sweet syrup.

During their tour of the sugarhouse, visitors also enjoyed homemade pancakes cooked by Niles’ father, Gary Niles, and ice cream smothered in warm syrup.

Michael Niles explained that his family leases trees and pays for the lease in syrup. They also use a new, smaller tap that is less invasive. “If I can put my arms around a tree, I only put in one tap,” explained Niles. “If my fingertips touch, I put in two taps. Three taps go in the really ancient trees.”

An average 40-year-old tree will yield about 40 quarts of sap per season, just enough to make one quart of pure maple syrup.