The owners of Black Ankle Vineyards in Mount Airy, Md., were visited by French soil experts during the pair’s first visit to the Eastern United States. One expert’s verdict: “Beautiful soil for a vineyard.” (Michael S. Williamson/The Washington Post)

As soon as he set foot on the dirt at Black Ankle Vineyards, Claude Bourguignon picked up a large clump and held it close to his nose for several seconds, then crumbled it in his hands.

“Beautiful soil,” he muttered in his deep, gravelly voice. “Beautiful soil for a vineyard.”

Bourguignon and his wife, Lydia, sported huge smiles, well-worn jeans and puffy vests and windbreakers to guard against the late-April chill. They resembled simple French farmers rather than the world’s most famous “soil doctors,” specialists in helping nurture dirt to produce healthier crops. They’ve consulted for golf courses, botanical gardens and agricultural farms, but their fame stems mostly from their work with winegrowers. They are especially popular with vintners who practice biodynamics, the beyond-organic growing method that views a farm as a living ecosystem. Their winery clients include some prestigious names: Romanée-Conti, Leflaive, Dujac and Château du Pommard in Burgundy; Selosse in Champagne; Pingus and Vega Sicilia in Spain; Harlan Estate and Bonny Doon in California.

“This is huge, having them come here,” said Ed Boyce, who with his wife, Sarah O’Herron, owns Black Ankle, near Mount Airy, Md. “I’ve followed their work for years, and if we can get them to work on the East Coast, they could have a big impact.”

The Bourguignons worked for the French National Institute for Agricultural Research in the 1980s but went independent in 1990 out of concern that official science cared for Big Agriculture more than for small farmers. The couple say overuse of herbicides and pesticides fostered unhealthy soils and weakened plants against disease, creating a vicious circle of increasing reliance on chemicals. From their private laboratory in Burgundy, called Laboratoire Analyses Microbiologiques Sols, the Bourguignons analyzed soils from around the world to identify common characteristics of healthy soils as well as features unique to each site.

Claude estimated that in the 24 years since they started their lab, he and Lydia had examined 12,000 soil pits — holes dug specifically for analysis — in locations around the world. Yet this was their first visit to the Eastern United States, made at the behest of vineyard consultant Lucie Morton, who works with Black Ankle. Their itinerary included stops at other Morton clients, including Sugarloaf Mountain Vineyard in Maryland and Boxwood Winery and Ankida Ridge Vineyards in Virginia. Claude was particularly interested in seeing the ancient soils of the Appalachian and Blue Ridge foothills, among the world’s oldest soils in geological terms.

Not too many years ago, East Coast viticulture was known more for its challenging climate, disease pressure and reliance on chemical sprays and less for the quality of its wines. That is changing, and it’s no coincidence that the wines are getting better as growers move toward more environmentally friendly farming techniques. Boxwood and Black Ankle, for example, do not use herbicides. Black Ankle and Ankida Ridge employ biodynamic techniques to promote healthy vines and ward off pests and disease.

There was no time for a soil pit at Black Ankle. Boyce welcomed the Bourguignons, Morton and two other Morton clients: Howard Wilson, who grows grapes near Newmarket, Md., and Tom Croghan and Polly Pittman, who own the Vineyards at Dodon in Davidsonville, south of Annapolis. Claude gave a brief tutorial on the importance of cover crops between vine rows to guard against erosion and promote vitality in the soil. Lydia produced a knife and demonstrated how to prune vine roots near the soil surface to discourage growth of secondary roots that would sop up surface water. Pruning those roots would encourage the main roots to dig deeper into the soils in search of nutrients, leading to stronger vines and better-quality grapes.

“The grapevine is unique in all the plants in that we prune both its leaves and its roots,” Claude said. It sounded rather romantic, but I could tell Boyce was calculating the toll on his back from doing that simple operation on his 80,000 vines over 42 acres of vineyards.

“We’ve had other soil scientists come through in the past, but most focus on the chemical composition of the soil,” Boyce said several days after the visit. “The Bourguignons focus on the microbiology and water management, and to our way of thinking, those are the most important aspects of vineyard soil. They came up with three or four ways to make our wines better just in the short time they were there. My head was spinning.”

At Boxwood Winery in Middleburg, Executive Vice President Rachel Martin was equally impressed. By looking at a four-foot-deep soil pit dug between two rows of 12-year-old cabernet franc vines, the Bourguignons “were able to tell the method of planting, the weather conditions when planting, the health of the vines and the progress of root development,” she said. “Hopefully they will return to analyze our old soils in the Mid-Atlantic and work with some wineries.”

McIntyre blogs at On Twitter: @dmwine.

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