Only a few people on Earth know where to find a stash of century-old rare mahogany that can be used to repair priceless furnishings damaged on Jan. 6 by a pro-Trump mob that stormed the Capitol.

Robert “Bob” Ross is one of those people. 

The acting assistant director of the U.S. Forest Service’s Forest Products Laboratory in Madison, Wis., knew the exact location of a 3,000-pound stack of the wood that was collecting dust. The 78 mahogany boards, likely brought to the Badger State as part of research into airplane propeller materials during World War I, sat in a basement storage stall for a century waiting for a purpose. 

“We actually had an allocation from the War Department to put together a propeller research laboratory,” he said. “And I believe these specimens were used in the research.” 

While the origin of the wood is hazy, Ross said he’s confident of several facts. The lab originally got it through a New York supplier called I.T. Williams & Sons, which harvested mahogany from places in Central America, Africa and Asia.

A flatbed truck hauled it 850 miles last month to Washington, where it will be used to repair doors and other parts of the Capitol damaged on Jan. 6, according to the Architect of the Capitol. The work to plane, cut and repurpose the wood is expected to begin in June. 

That same old-growth wood, prized for its durability, straight grain and reddish-brown color, can’t be purchased today. The trees have protected international conservation status. 

“The old-growth mahogany that the Forest Products Laboratory has had in their safekeeping since the early 20th century and has now transferred to us is truly invaluable and is unavailable at any price, anywhere in the world,” said Mary Oehrlein, the AOC’s historic preservation officer.

The boards, each measuring 11.9 inches by 12 feet, will be used “to restore historic millwork in the nation’s temple of democracy,” said Architect of the Capitol J. Brett Blanton. “Our skilled woodworkers will use both traditional and modern carpentry techniques to create new millwork and doors using this repurposed wood.” 

It’s not clear exactly which pieces the wood will be used to repair, but in the aftermath of the mob attack, damage could be seen on high-profile doors, including ones that open to the House chamber. 

With its 60 research scientists, the lab has been a player in both civilian and military wood tech since it opened in 1910. It has helped develop new types of strong and economical engineered wood products for structures, new packaging for shipping containers, lightweight parts for planes and recycling-compatible self-stick stamp adhesive.

“There’s a lot of history here, and there’s a lot of outstanding research, reports and things like that,” Ross said.

The wood enthusiast and Michigan native has worked for over three decades at the facility. One of his specialties is using ultrasound and X-ray technology to evaluate the integrity of wood without destroying it. 

“It’s parallel to the people who develop equipment for the medical profession to look inside people — only I do it for wood,” he said. 

He’s been consulted by restorers of the USS Constitution, also known as Old Ironsides; New Orleans officials rebuilding after Hurricane Katrina; and even a St. Louis, Missouri, museum that asked for an assessment of the condition of a 2,500-year-old mummy’s coffin.  

Ross said he initially heard of the need for wood at the Capitol when he got a call from Nathan Kamprath of the U.S. Army Combat Capabilities Development Command, who leads a joint project between the lab and the Department of Defense.

“They asked me if we could help out with some of the things that were going to have to be replaced in the Capitol. I said ‘sure,’” he said. 

The lab has a whole library of rare and unique wood types, but its basement stalls still have piles just sitting and waiting. 

“I wouldn’t say we’re the equivalent of a Home Depot — I mean, we don’t have that much left,” Ross said. 

Where that other wood one day ends up is anyone’s guess. But to have some of these boards, once marked for research aimed at improving America’s WWI war machines, make their way to the halls of power in Washington seems fitting, he said.

“I’ve worked on some pretty important projects. Katrina was a real, real tough one for me because of the loss of life,” he said. “But to think that I could help out, and the laboratory can help out, in a small way in the rebuild of the Capitol — it’s just an incredible feeling.”