It was a strange sound on a quiet, drizzly day at the Back Bay Fens — the growl of a chainsaw buzzing from the depths of the sleepy community garden.
Norm Helie, a plant and soil scientist, thought to investigate. He came upon two men, without city uniforms, standing over a chunk of wood they said came from Jamaica Plain. His eyes landed on the specimen: a beautiful knot of ornately patterned red oak. Fishy, he thought. He walked away, then called 911.
“I’m not a confrontational person,” Helie said. “Especially when somebody has a chainsaw.”
Police later arrested a man in connection with a string of mysterious tree burl thefts that have plagued the Boston area for months.
Michael Scanlan, 44, was charged Wednesday with willful and malicious destruction of property. He was seen by a witness shaving scrap pieces off the burl in the park, then leaving with the chainsaw and entering an apartment building across the street, at 15 Park Drive. Police searched the building, found Scanlan’s door, and asked to speak with him.
Scanlan admitted he had used a chainsaw to cut off bits of the wood in the Fens, but said the original slab had been dropped off by a friend, according to police. He told police he could not remember his friend’s name.
Police have not yet found the tree from which the burl was removed.
Scanlan is scheduled to be arraigned Thursday morning in Roxbury District Court. The other man with Scanlan in the garden was arrested on unrelated drug possession charges, according to a Boston police spokesman, David Estrada.
Tree burls are deformations on the surface of a tree trunk, gnarled and ornate knots that can fetch $50 to $500 per piece from woodworkers who turn them into ornate bowls, artwork, or furniture pieces.
Last spring, the city’s arborist, Greg Mosman, noticed that burls had been sliced from trees in Franklin Park, Symphony Park, Evans Way Park, and Rambler Park. The vandals were undiscriminating in their attacks — oaks, lindens, hemlocks were targeted, at least a dozen in total.
Cutting off a sizeable chunk can be detrimental to the tree, Mosman said. Although the raw wood will seal over, the wood beneath the seal will rot, eventually killing the tree.
“It’s not like it’s going to die today or tomorrow,” Mosman said. “It’s going to take years.”
Mosman said it has been a real change for the arborist more accustomed to fielding complaints about routine branch prunings and tree removals than clandestine black-market amputations.
When he received the call that a potential burl burglar had been apprehended, he wondered whether the sighting was real.
“I go flying out of the office, then I thought, are the guys playing a joke on me?” Mosman said.
Helie specializes in plant diseases and was hired by the Friends of the Fenway Victory Gardens to help maintain plant health.
Mosman told him weeks ago about the burl thefts. At 9 a.m. Wednesday, as he was on a routine assignment checking tree trunks for elm bark beetles, he heard the revving of the chainsaw and immediately thought of the burl theft mystery.
“I’m usually catching diseases and insects on trees, not people,” Helie said.
Left behind at the park was a pile of sawdust and rotted wood that Helie believed had been cut away from the valuable knot of wood.
“This doesn’t do it justice, because it’s all dissected,” Helie said, gazing at the discarded wood.
Burls fascinate more than just tree enthusiasts like him, he insisted. People who do not know the first thing about tree biology find the delicate patterns and swollen, coiled exterior mesmerizing.
“It’s not just me,” he said. “There’s a beauty to it that I think should remain a part of the parks — shouldn’t be taken away by people who think it’s their own.”
Police took the burls found in Scanlan’s apartment into custody. Brookline police were called to help compare the detained burls with the two Brookline trees that had been vandalized, but they found no matches, Brookline police Lieutenant Philip Harrington said.