In Chanhassen, the first sign of spring wafts from the rafters of the Sugar Shack, expelling the unmistakably sweet scent of maple syrup.

It’s here, inside a small cabin at the Minnesota Landscape Arboretum, that thousands of gallons of tree sap are boiled into America’s favorite breakfast condiment.

Production is arduous, requiring around 35 gallons of sap to yield a single gallon of maple syrup.

“That’s why the cost is so high — you need a lot and it’s a labor of love,” program volunteer Steve Hanson explained to a group of touring schoolchildren.

Syruping typically peaks in March, when temperatures warm to at least 40 degrees by day, sending sap up the trunks, but still dipping below freezing at night. This year, because of an unusual freeze-thaw cycle, spring was sprung three weeks early. As a result, the arboretum recorded its earliest tapping date on Feb. 8, leading to its longest-running production season — now at 45 days and counting.

Minnesota produces less than 1 percent of the country’s maple syrup, lagging far behind such power players in the Northeast as New York and Vermont. Even so, maple syrup production has become the most popular educational program at the arboretum, which runs a modest commercial tapping operation with nearly 400 trees.

The classes draw 1,500 students from around the state each year. Children learn that American Indians were the first to manufacture syrup, a technique later adopted by European settlers. After identifying a mature sugar maple, students take turns drilling a tap hole, where they insert a spike and attach a plastic collection bag. Throughout the woods, tools from various eras of syrup remain: steel buckets affixed to a few trees and an old-fashioned wood-burning stove for cooking smaller batches.

“Collecting sap in birch bark wasn’t the most efficient,” Hanson said of the earliest methods. “Now we have tubes that bring it to us. Life is a lot simpler now.”

Simpler, but still tedious.

On half of the trees, a gravity system pulls the sap downhill. The other trees are attached to a vacuum pump that carries sap to a large vat — the more efficient method used by commercial producers. The sap is then boiled in a large stainless steel evaporator that can cook as much as 80 gallons of sap an hour.

“It’s like having a rocket when you’re used to having a tricycle,” arboretum spokeswoman Susie Hopper said of the industrial-grade machine.

Cooking the syrup requires vigilance, as it burns easily. So far, the arboretum has transformed about 3,300 gallons of sap into 95 gallons of amber syrup. Workers expect to produce at least 10 more gallons before trees bud, when the season taps out.

Guests who venture inside the Sugar Shack, which houses the evaporator and a small classroom, are treated to an edible experiment.

First, kids sip from a paper cup containing uncooked sap. Fresh from the tree, the mildly sweet, clear liquid more closely resembles tap water than the gooey treat that gets poured on pancakes.

“I thought it was going to be sticky,” one little boy shouted. Another described it as “sugary water.”

In this form, sap contains only about 3 percent sugar. Finished syrup requires a 66.5 percent sugar content — about six times sweeter than a can of cola. Real maple syrup can be a budget buster, often selling for double or triple the price of popular supermarket syrups such as Aunt Jemima, Hungry Jack or Mrs. Butterworth. These contain only maple flavoring and are made from high-fructose corn syrup. An 8-oz. bottle of arboretum syrup runs $12.95 in the visitor center.

Mindy Zittel, the arboretum’s children’s education program associate, said real maple syrup costs more because it springs from a combination of people power and good weather. “We’re really dependent on Mother Nature,” Zittel said.

For that reason, Richard DeVries, who runs the horticulture garden’s syrup production, suspects that most children have never tasted the authentic stuff. But during a blind taste test, students could overwhelmingly tell the difference between the maple-flavored syrup and the genuine article.

Most maple syrup — 80 percent of the world’s supply — comes from small swath of Canada, particularly in Quebec. Minnesota has 10 million tappable maples scattered throughout the state, DeVries said, but it will never keep pace with states where syruping helps drive the economy.

Hobby tapping grows

Large commercial operations are less common here, but hobby tapping is growing. The interest could be part of a larger back-to-basics trend that has driven consumers toward locally sourced foods, said Shelly Carlson, vice president of the Minnesota Maple Syrup Producers Association, a nonprofit that offers resources to maple syrup hobbyists and commercial outfits. Membership in the group is at an all-time high — 130 and growing.

Some regional parks offer how-to syruping classes throughout March. Three Rivers Park District hosts several open houses this weekend. Popular syrup festivals, like the one starting Saturday at St. John’s University, have also drawn attention to the craft. Some stores have begun stocking maple tapping starter kits.

“You see a lot of bags, buckets hanging on trees,” Carlson said. “The demand is there.”

At the Arboretum’s annual pancake brunch last weekend, nearly 1,500 hungry guests piled their plates high with a maple-inspired menu.

Richard Johnson, of Minnetonka, took the opportunity to drizzle homemade maple syrup in his coffee. A self-described addict, Johnson keeps a 2-oz. bottle of the sweet stuff in his backpack. “Everyone probably thinks it’s bourbon,” he said, describing how he spikes drinks with syrup in cafes.

The arboretum’s pancake brunch has become a family tradition for Jen Toavs and her two young sons. It provides an opportunity for her kids to get out in nature and experience the whole process from beginning to end.

“It doesn’t appear in a bottle on the table,” she said of the syrup. “The trees are what’s providing the syrup — that’s why it’s so important to take care of them.”