By AMANDA OGLESBY • STAFF WRITER • February 17, 2010
Forester Bob Meierjurgen is seeking sweetness armed with a power drill. It is maple tree-tapping season, and Meierjurgen and forester John Burkle are drilling into maple trees at the Forest Resource Education Center in Jackson and Monmouth Battlefield State Park in Manalapan.
Maple syrup is maple sap boiled to remove most of its water. The process requires days of boiling in the Education Center's Sugar Shack, a wooden one-room building in the woods off East Veterans Highway.
Out of the tree, the sap contains about 1.8 percent sugar, Burkle and Meierjurgen say. To become table-ready maple syrup, the water must be boiled out to concentrate the sugar, which will make up about 62 percent of the syrup.
For years, the foresters tapped the local red maple trees at the Education Center.
"We used to have to collect 80 gallons of sap to make one gallon of syrup with red maple" says Burkle.
Now, the two tap sugar maple trees at Monmouth Battlefield instead, which produce a higher-sugar sap.
"It cuts 40 gallons of water that we don't have to boil off," Burkle says.
To tap a maple, Meierjurgen approaches the warm, south-facing side of the tree with a power drill. Angling the drill bit up slightly, he makes a two-inch hole into the trunk. He inserts a "spile," a metal tube that directs the sap into a hanging bucket. Clear, watery sap begins to drip within minutes.
Just one tree can fill a large metal bucket within 24 hours, they say. Burkle and Meierjurgen have a limited time to collect sap, because the tapping season lasts about three weeks in New Jersey.
"We're kind of outside the natural range where sugar maples grow right here," Burkle says, adding that sugar maples grow naturally in colder or northern parts of the state.
The season is limited by the environmental conditions required for sap collection. Freezing nights and warmer days provide the best conditions, Meierjurgen says.
"Once the weather breaks, you're getting that perfect freeze and thaw scenario for the pumping action from the sap," Meierjurgen says. "That's what we need, above freezing and below freezing."
Wild animals pose problems, too. Deer, mice, rabbits and woodchucks have eaten some of the sugar maple saplings planted at the Education Center.
"Maples are sweet. They know it, too." Meierjurgen says. "They're like little beavers."
By the end of February, the harvest season is over.
The foresters take their gallons of the sap back to the Sugar Shack, where with the help of seasonal employee Rick Bentz, they boil it over a wood-burning brick fireplace. Clouds of white steam billow up to the ceiling and escape through a screened cupola.
"This is a basic evaporator, (with) a wood fire," Burkle says. "It's sap in and syrup out."
"We're evaporating the water from the sap, so the sugar amount is stronger," Meierjurgen says.
The cold sap sits in a warmer before it moves to the tray above the flames.
"You don't want to pour something cold, almost slushy, into something boiling," Meierjurgen says. "We (would) lose the potential power of the boiling water.
"It's kind of a fun science," he adds. "We can have it drip in as fast as it's evaporating, so it's kind of a safe equilibrium."
The boiling sap is never left untended, because within a minute, it can boil over the sides of the evaporator and be ruined, they say.
Once the syrup nears the desired consistency, they move it to a finishing pan powered by propane. The pan gives them more control over the temperature in its last phase of the process. They measure its sugar content using hydrometers, and after confirming that sugar comprises about 62 percent of the syrup, Meierjurgen bottles it. It is used for education purposes at the center.
"It's a very simple process, but you have to think about the acreage," Meierjurgen says. "You need a lot of trees, heat, (and) dedication. It's a very expensive practice."