SONOMA -- The Donum Estate, a maker of pinot noir wine based in the Los Carneros winegrowing region of southern Sonoma County, acquired the 20-acre Nugent Vineyard in Russian River Valley.

Donum acquired property, which has 16 acres of pinot noir vines, from owners Joe and Cynthia Nugent, who planted it for Donum on the guidance of Anne Moller-Racke, president and winegrower. The purchase price was undisclosed.

“Anne and Joe Nugent have enjoyed a wonderful working relationship through the years that has produced spectacular results,” said Trond Fredheim of Winside, Inc., a partnership of Danish investors that bought Donum less than a year ago. “We are delighted that Joe has entrusted ownership of this special site to our winery.”

Since 2005, fruit selected from lighter soils in blocks on the northern and southern extremes of the vineyard has gone into Donum’s estate grown Russian River Valley pinot noir. The five vintages released to date have received Wine Spectator ratings ranging from 91 to 95 points, averaging 92.8. Last year, the inaugural release of Donum’s Russian River Reserve, a 2009 vintage limited “best barrel” selection, received a 96-point rating.

Nugent Vineyard is divided equally between Dijon pinot noir clones 667 and 115 in the northern and southern blocks, respectively. The Russian River Valley wine consists of equal parts of each clone. The reserve wine is entirely 667.

The vineyard was originally 11 acres. Five acres of Pommard selection were planted to the west, and a 2011 vintage from this “Ten Oaks” parcel is forthcoming.

“We could not have asked for a better partner than Joe Nugent, because he has understood and supported our grand cru model for pinot noir,” Ms. Moller-Racke said. “We farm all of our vineyards to the same high standard, and we focus on finding those special blocks or portions of blocks where the clone or selection aligns perfectly with the site to offer pure expression in a complete wine."

The winery has begun planting an additional 15 acres of Pommard and Calera selections at the 147-acre Donum Ranch in Carneros. An 2011 pinot noir wine from Mendocino County's Anderson Valley also is in barrel.

Donum currently produces both a Carneros pinot noir and a chardonnay as well as two pinot noir crus, East Slope and West Slope, from its 45 planted acres at Donum Ranch.

“Our goal is not to increase production, but to identify more exceptional sites capable of consistently producing grand cru level wines,” noted Daniel Aaxman, another Winside partner.

Retail prices for Donum’s Russian River Valley pinot noir wine is $70 a bottle and for the reserve, $90.