The ethanol-fueled fungus known as whiskey fungus has thrived for centuries around distilleries and bakeries. It’s been the source of complaints from residents who live near Kentucky bourbon distilleries, Canadian whiskey makers and Caribbean rum manufacturers.
Now, it is driving a wedge between some residents of Lincoln County, Tenn., and Jack Daniel’s, the famed distillery founded in 1866 in neighboring Moore County.
For months, some residents have complained that a sooty, dark crust has blanketed homes, cars, road signs, bird feeders, patio furniture and trees as the fungus has spread uncontrollably, fed by alcohol vapors wafting from charred oak barrels of aging Jack Daniel’s whiskey.
Jack Daniel’s has built six warehouses, known as barrelhouses, to age whiskey in the rural county, which is home to about 35,000 residents, and is building a seventh on a property that has room to house one more, a company spokesman said. The distillery has asked the county to rezone a second property where it could build six additional barrelhouses.
A company representative, Donna Willis, told county officials in November that 14 barrelhouses would generate $1 million in annual property tax revenue for the county, which had approved about $15 million in general fund spending for the 2022 fiscal year.
But not all residents are happy about the expansion.
Christi Long, the owner of a local mansion built in 1900, which she operates as a venue for weddings and other events, sued the county in January, contending that barrelhouses near her property lacked the proper permits.
A judge last week ruled that one barrelhouse currently under construction had not been properly approved and that its building permit would have to be rescinded until Jack Daniel’s obtained the necessary permits.
Ms. Long’s lawyer, Jason Holleman, said he planned to ask the judge and the county to stop Jack Daniel’s from using other barrelhouses near Ms. Long’s 4,000-square-foot mansion, known as the Manor at ShaeJo.
Ms. Long and her husband, Patrick Long, said that whiskey fungus had already inundated the property, darkening the copper roof and exterior walls, creeping over the rock garden and metal gate and encrusting the branches of magnolia trees. Nearby, it blackens metal road signs, they said.
The Longs said they use a high-pressure hose to wash the property every three months with Clorox bleach and water, but the fungus always returns.
“If you take your fingernail and run your fingernail down our tree branch, it will just coat the tip of your finger,” Mr. Long said. “It’s just disgusting.”
Ms. Long said her corner of Lincoln County “is going to be black as coal” unless Jack Daniel’s installs air filters in the barrelhouses, one of which sits about 250 yards from her property.
“This fungus now is on steroids,” she said.
A lawyer who represents Lincoln County declined to comment, citing the continuing litigation.
Melvin Keebler, general manager of the Jack Daniel Distillery, said in a statement that the company “complies with all local, state, and federal regulations regarding the design, construction, and permitting of our barrelhouses.”
“We are committed to protecting the environment and the safety and health of our employees and neighbors,” Mr. Keebler said.
At a county commission meeting in November, Ms. Willis, the director of technical services, maintenance and barrel distribution at Jack Daniel’s, said that studies have shown that the fungus is not hazardous to human health and does not damage property.
“Could it be a nuisance?” Ms. Willis said. “Yeah, sure. And it can easily be remedied by having it washed off.”
She said the company would not agree, however, to power-wash homes, saying Jack Daniel’s could be held liable for any damage.
Ms. Willis also said that air filters could hurt the flavor that Jack Daniel’s whiskey acquires during the aging process. Distillers refer poetically to the liquor that evaporates during that process as “the angel’s share.”
The fungus that thrives off the lost alcohol has been noted at least since the 1870s, when Antonin Baudoin, the director of the French Distillers’ Association, observed a “plague of soot” blackening the walls of distilleries in Cognac, France.
James A. Scott, a professor at the Dalla Lana School of Public Health at the University of Toronto who has studied the fungus since 2001 — and helped name its genus, Baudoinia, in honor of Baudoin — said he was not aware of any research specifically looking at the health effects of exposure to the fungus.
But the fungus can destroy property and can cling to almost any surface, he said. A puff of alcohol, Dr. Scott said, makes it remarkably resistant to temperature changes, allowing it to withstand hot summers in Tennessee.
“The fungus is pretty destructive, and the only way to stop it is to turn off its alcohol supply,” Dr. Scott wrote in an email. “It wrecks patio furniture, house siding, almost any outdoor surface. I’ve seen trees choked to death by it. It is a small mercy that it does not also appear to have a negative impact on human health.”
Tracy Ferry said she and her husband, Warren Ferry, who bought a home in Lincoln County three years ago, were hoping that Jack Daniel’s would installs air filters.
Ms. Ferry said that since Jack Daniel’s built a barrelhouse next to her house in December, whiskey fungus had been accumulating on the roof of her home and car and on trees on her property. She said she had scrubbed the paint off wooden patio furniture while trying to remove the dark growth.
“I could try and sell, but what am I going to get?” Ms. Ferry said. “Who’s going to want to live here?”
