Small pipes running from tree to tree create an interconnected maze on Aaron Morse’s 150-acre property in Marshall, Michigan. Their destination? The property’s sugar shack, where sap from Morse’s many maple trees collects from late February to early April to be boiled into maple syrup, the key ingredient in 3 Pairs of Legs and 6 Pairs of Legs maple porters at nearby Dark Horse Brewing Co., which Morse owns.

“We ended up around 275 gallons of actual syrup, which, times 40, gives you the amount of sap,” said Morse shortly after this year’s harvest. “It was a good season, not quite as much as I wanted, but good.”

Usually synonymous with pancakes and waffles, maple syrup is now being used by a number of breweries, including Dark Horse, to create beers where it serves as the sole source of sugar, replacing malt and other fermentables. The result, conceivably, will be a beer that tastes of maple syrup’s distinctively toasty, woodsy and caramel-like sweetness.

But according to brewer Sean Lawson of Lawson’s Finest Liquids in Warren, Vermont, a man who has won multiple awards at the Great American Beer Festival for his maple beers, the process is not so black and white. According to Lawson, brewers must construct what drinkers perceive as maple syrup’s presence in their beer.

“It’s taken years of developing recipes and trial to make a maple beer where it really has a distinct maple character to it—it’s not easy to achieve,” Lawson says.

Sean Lawson poses for a portrait outside his home-based microbrewery, Lawson's Finest Liquids, in Warren, Vemont. photo by Monica Donovan for the Boston Globe
Sean Lawson of Lawson’s Finest Liquids

Lawson began brewing maple beers as a homebrewer after college because maple, to him, was more connotative of Vermont than were other ingredients.

“It’s a local ingredient, whereas malted barley is hard to come by,” he says.

The primary problem in retaining maple syrup’s flavor, Lawson says, is the fact that yeast will ferment almost all, if not all, of the maple sugars that impart maple syrup’s distinctive sweetness.

“You’re going to get maple flavor, not maple sweetness,” he says.

For Lawson, the first key to creating a distinct maple taste despite the absence of maple sugar is to build a specialty grain profile that brings forth the maple flavors left behind after fermentation while restoring the maple-associated sweetness via residual sugars.

“Caramel malts, crystal malts like honey malts—those mid-range malt-type flavors where you’re getting dark fruit, caramel or toffee out of them, those end up matching up in the end with the maple profile,” says Lawson.

“I need to build in the sweetness you’d expect from the grain.”

Besides a particular selection of grains, Lawson also says that, for him, the use of anything but mild, low alpha-acid noble hops like Saaz and Hallertau, or American variations of them such as Vanguard, overtakes the maple taste he wants for his beer.

Dark Horse employs a similar ethos to achieve the maple flavors in its 3 Pairs of Legs and 6 Pairs of Legs maple porters. Both were inspired by a morning spent “bumping around and eating pancakes,” says Bryan Wiggs, Dark Horse’s brewery operations manager, and are made using the syrup that the brewery produces itself.

“We try to keep it in that porter category and on the maltier side of things so that that maple becomes a little more present, instead of taking away with things like roasted barley or West Coast American hops,” says Wiggs.

Lawson’s Finest Liquids and Dark Horse both use barrel aging to further the maple’s prominence in their beers. Lawson’s uses barrels that once housed maple liqueur for some of its beers’ production while Dark Horse uses bourbon barrels to age its 3 Pairs of Legs porter. For Dark Horse’s 6 Pairs of Legs porter, the brewery ages maple syrup in bourbon barrels (that syrup is also packaged as its own specialty product), then uses the same barrels from that process to age the porter.

The vanilla and woody characteristics of barrel aging, Wiggs says, “lift the maple characteristic up,” an effect further accentuated by the residual maple flavor left in barrels that Lawson’s uses and the 6 Pairs of Legs barrels that Dark Horse employs.

But not all brewers see maple as a brewing centerpiece. For Chad Henderson, head brewer at NoDa Brewing Co. of Charlotte, North Carolina, maple was a promising new way to bring out big hoppy flavors in a beer.

Henderson envisioned big, juicy and piney hop flavors for Hop Cakes, the brewery’s seasonal double IPA, and the lack of specialty grains, he says, allows the beer’s big hop bill to shine uninterrupted.

Hop Cakes, which is made with maple syrup, uses a standard grain bill devoid of any of the specialty grains that would normally add deeper color and toasty, caramel, nutty or grainy flavors to a beer.

Maple syrup acts as a quiet substitute and rounds out the beer by adding back in a subtler version of those characteristics, on top of a touch of distinctive sweetness, Henderson says. The syrup also adds an extra alcohol potential that gives the beer its 10.2% ABV.

“With the hops there and the sugars fermenting out, the maple syrup doesn’t leave so much sweetness, but without the specialty malts it becomes the specialty malts,” Henderson says.

While maple syrup isn’t perishable and maple beers aren’t restricted to maple season, they are restricted by maple syrup’s premium price.

Lawson notes that while grains may run him 40 cents to around $1 per pound, maple syrup runs between $3 and $4 per pound and doesn’t contribute much more sweetness by weight.

“Maple is wicked expensive; there is not an adjunct that is more expensive,” Lawson says.

For reference, it takes Lawson 165 pounds of maple syrup to make one batch of his brewery’s imperial stout. Dark Horse Brewing decided to deal with that prohibitive cost problem by producing its own maple syrup. At first the brewery just boiled local producers’ sap into syrup in its kettles, but after a sap shortage scare and Morse’s realization that he could cut costs by harvesting the sap himself, the brewery started its sugar shack operation on his property.

The brewery sells some of its syrup on its own—including the barrel-aged syrup that allows for the creation of 6 Pairs of Legs—but uses the rest to brew its maple beers.

This season, since Morse’s sap collection wasn’t above normal, Dark Horse won’t have any new maple beers in the works. However, Morse says that will change next year as the number of maple trees on his property expands.

“That’s the fun part about having that opportunity,” says Wiggs. “If we get a really good March and April, we’ll definitely expand into other styles.”

This season’s sap and syrup will show up in Dark Horse’s 3 Pairs and 6 Pairs of Legs releases this September. Lawson’s award-winning Maple Trippel, which is brewed with only fresh sap and no water and is barrel-aged for a year before being blended with some of the current year’s batch and bottled, will be available starting this summer.

Bo McMillan is a freelance writer and student based in Chapel Hill, North Carolina. He has contributed in the past to Creative Loafing-Charlotte and CNBC and occasionally maintains an affordable cooking blog, Gourmen, with his housemates.