(Jay Paul/for The Washington Post)

The thieves allegedly arrived in the dark of night and worked quietly and meticulously to steal their items — 2½ tons of grapes that the owner of the Virginia vineyard says were on the cusp of being harvested.

It’s a loss worth $50,000 in supplies, labor and potential wine sales for Firefly Hill Vineyards in Elliston, near the Blue Ridge Mountains, about 20 miles from Roanoke.

David Dunkenberger, who has owned the family-run vineyard for 12 years, said he doesn’t know who could have taken the grapes or what the thieves might plan to do with them. He said he doubts another winery would purchase grapes without knowing their history and suspects the thieves might try to sell them outside the area.

“I can handle losing a crop to Mother Nature, but to come in and take my crop in the middle of the night and steal what we’ve worked for for eight months, that’s disheartening,” he said.

Dunkenberger, who lives about a 10-minute drive away, said his daughter took samples of the grapes Sunday, and the family planned to harvest them Tuesday. Dunkenberger said he and his father showed up that morning and “everything was gone.” They suspect the heist occurred earlier that morning.

Dunkenberger estimated it would have taken his team of eight people about 12 hours to pick the grapes and process them properly. Vandals probably made away with his crop in much less time, he said.

“If they were cutting, they could have picked it clean in six hours,” Dunkenberger said. “I have no idea what they will do with them.”

He shared his feelings in several Facebook posts, describing how the 36-acre vineyard is a family experience and how his daughters, his father and others help during the season.

“Cherished memories spoiled by a bunch of low life, no soul, heartless excuses for human beings,” he wrote.

Capt. Brian Wright, a spokesman for the Montgomery County sheriff’s office in Christiansburg, Va., which is investigating the grape theft, said the “million-dollar question” is the whodunit.

A police report indicated “the victim discovered a crop of grapes about to be harvested had been stolen overnight.” Wright said it appeared the grapes had “just been cut off the vine.”

He said the case was unusual for the agency.

“We’ve had cases of plants being stolen,” he said. “The occasional shrubbery or ornamental trees. But we’ve not had a large case of crops.”

A bird netting that normally covers the grapes was still in place when Dunkenberger arrived Tuesday morning. He said the thieves apparently removed the netting, cut the grapes, then replaced it.

Dunkenberger said he expected to have a good crop this year, despite heavy amounts of rain that could have damaged the grapes.

He had planned to use the grapes for two French-American hybrid wines. But with fewer than 200 pounds of grapes available, the business is closed for the time being.

“You work your whole year for the harvest day and we were about to have that,” he said. “We were almost there, and somebody stole it.”