Posted: Thursday, October 25, 2012 12:00 PM
Sean Ellis/Capital Press
A wine grape vinyeard in the Sunny Slope area of Caldwell, Idaho, is shown in this recent photo. A study that mapped the entire Snake River Valley AVA will help growers determine the optimal grape-growing sites in the region.
Federal grant paid for analysis of 8,263 square miles of AVA
By SEAN ELLIS
A project that mapped the entire Snake River Valley American Viticultural Area to determine the optimal sites to grow grapes could help pave the way for the Idaho wine industry's future growth.
The Idaho Wine Commission study, completed this year, was led by winemaker Greg Jones, who heads the department of environmental studies at Southern Oregon University.
The commission used a $100,000 federal grant to finance a climate and landscape analysis of the 8,263-square-mile AVA, which includes 1,600 acres of vineyards.
The study, available at the IWC website, will help growers determine the best match between site and grape variety.
Bitner Vineyards owner Ron Bitner, the principle research coordinator for the study, said the research will be important for Idaho's fast-growing wine industry.
The number of Idaho wineries has increased from 32 to 49 in the past four years, and Idaho's total wine production has risen by 50,000 12-bottle cases during that time.
Bitner said a key finding of the study is that less than 100,000 acres in the AVA should be considered for planting. That leaves plenty of room for growth but makes site selection extremely important.
"We are a growing industry here in Idaho and the ability to pinpoint ideal growing sites here in high-desert country is essential to know before spending $12,000 an acre or more to plant winegrapes," he said. "Site selection and varietal selection are the keys to the growth of our industry."
The research matches various grape varieties with their ideal climate, elevation, slope, solar receipt and soil property needs.
"It's a big investment to put a vineyard in," said Maurine Johnson, winemaker for Ste. Chapelle, Idaho's largest winery. "The trick is finding the right site for the right variety and this research is going to help us a lot."
The study found that the region's cool to warm climate gives Idaho growers the ability to plant a wide range of different varieties, but frost and a short growing season are the main limiting factors.
Because of this, the study says, it's important to select sites that are less inclined to early frost and to pick varietals that bud late and ripen early.
Winemaker Martin Fujishin, who teaches viticulture at Treasure Valley Community College, said the mapping study is important to the industry because Idaho winemakers want the highest-quality grapes.
"If you're going to raise grapes here in the AVA, you want to be raising grapes on the optimal sites," he said. "The last thing we need here in Idaho is to be raising grapes that are not of the highest quality."
The study contained some surprises, he said, such as the finding that some of the warmest sites in the AVA are not in the traditional grape growing region near Caldwell.
"That opens up opportunities for people that are not necessarily right here in the Sunny Slope area to actually grow grapes," he said.