BROWNFIELD — Looming large in the woods on the western edge of Maine, the elongated 1908 barn with a gambrel roof has been used hard. No gentlemen farmers ever gussied it up.

The well-worn behemoth with chipped paint, dismantled silos and defunct weather vanes has experienced a century of endeavors. It housed Jersey cows, served as a hatchery and survived seasons of ski house shenanigans. Today, the wholesome scent of roasted oats and nuts wafts through the air among the beams and crannies.

Fifteen years ago, this barn became the home of GrandyOats — a fast-growing granola, nut and trail mix company. In Maine’s burgeoning food economy, GrandyOats has blazed an inspiring trajectory, and the barn has been central to that success.

“It’s a wonderful place to produce,” said Aaron Anker, chief granola officer and co-owner of GrandyOats. “We’ve grown into it organically. Like a Rube Goldberg, we’ve kept expanding into the facility.”

Erected as a big, rural working factory, it was the state’s largest barn when it was built. Now it suits this company’s multiplying roster of natural, organic and non-GMO products. From maple roasted cashews to coconut and fruit granola, everything is made by hand by humans on the first floor.

GrandyOats products, sold in natural food stores and institutions around the country, are made in former horse stalls that now are occupied by industrial ovens, hand mixers and the wholesome aroma of baked oats.

“This building was like an envelop,” Anker said. “We kept building into the envelop.”

They poured concrete to level the floor and kept beadboard ceilings and walls, maintaining some signs of the past. A few chutes carved into walls remain, but instead of hay or manure, “it smells like an Italian restaurant,” said “head honcho” and GrandyOats co-owner Nat Peirce, as the production of garlic herb cashews was under way on a recent afternoon.

Founded in 1979, the company moved from Bridgton to build its healthy empire in this truss-supported structure.

“I bought the barn at auction 15 years ago,” said Peirce, who used to live in an apartment upstairs, which now serves as GrandyOats offices and breakroom. “It was a screaming deal.”

Four years ago, a packaging room was built in an open upstairs space Anker called “the room of infinite potential.” Now it’s lined with rows of boxes ready for shipment.

Like the string of owners that have left their mark on this country factory, GrandyOats has its own share of tales. A splintered barn door leading to the storage room is legendary.

“A bear broke in one day and took off with a 25-pound box of organic California almonds,” Anker said.

Peirce smiled and said, “It wasn’t really funny.”

To keep up with the company’s 25 percent growth year after year, the owners are planning to sell the barn and move to a former school in neighboring Hiram. So the barn will soon be for sale again.

“It’s impacted who we are,” Anker said. “The company is 36 years old, and for a good chunk of that time, the barn was part of our story.”

As the owners prepare to move from the barn, which has served as their logo and is part of their ethos, they seem proud of their time here but ready for the next phase.

“What we have proven here is you can do it in a nontraditional space,” Peirce said. “We have put something to use that might have fallen apart.”

The century old structure awaits its next incarnation