Harvest is in full swing around California, and in a little corner of the Livermore Valley, that means a flock of sheep is busier than usual.

The 80 sheep grazing Tenuta Vineyards are not stomping grapes (purple fleece -- wouldn't that be a sight!). They are helping Tenuta owner and winemaker Nancy Tenuta remove weeds in her 14-acre estate vineyard of pinot noir and chardonnay grapes, just in time for the winery's 10th anniversary.

The mini sheep, a heritage English breed short enough to pass under the vineyard's irrigation drip line, replace chemicals and tractors in the vineyard and help cut down on air and noise pollution as well as the use of fossil fuels.

Belle and the wooly sheep work among the vines at Tenuta Vineyards in Livermore.
Belle and the wooly sheep work among the vines at Tenuta Vineyards in Livermore. ( Tenuta Vineyards )

The practice isn't new. Vintners who farm organically and biodynamically regularly host furry weed munchers. But for someone like Tenuta, a former stock trader who farms commercially, it's a nice way to be a little green.

To hire the sheep, which belong to Livermore rancher Allison Batteate, Tenuta applied for a grant through the U.S. Department of Agriculture's Environmental Quality Incentives Program, which provides assistance to agricultural producers who want to implement conservation practices.

Last year, the program became available to vineyard owners, says Batteate. It takes 15 sheep a week to clean up an acre of vineyard, she says.

"It is labor-intensive, but they don't charge," Batteate says. "And they distribute free fertilizer."

To show her thanks, Tenuta treated her flock to a spa day when they reported for crush last Sunday. Local sheep shearer Russ Duguid sheared their woolly fleece and gave them proper mani-pedis, or hoof trims.

The shearing helps protect their wool from stickers, like foxtails, that are found in weeds and other unwanted vegetation.

"They'll be with me for six months," Tenuta says. "We want to take good care of them."

Contact Jessica Yadegaran at jyadegaran@bayareanewsgroup.com, or follow her at Twitter.com/swirlgirl_jy.