Ashes to ashes, grapes to wine

By Soncirey Mitchell
Reader Staff

Idahoans feel the impact of climate change every summer when temperatures skyrocket and fire season fills the air with smoke. Rising temperatures around the globe are affecting long-standing wine regions, going so far as to drive French Champagne houses to buy property in England’s cooler climate. If this trend continues, regions like the Sonoma and Napa valleys could eventually become inhospitable to all but the hardiest grape vines; and, even then, the quality of their wine would deteriorate.

What’s bad news for California may be good news — momentarily — for Idaho vineyards, which have long been overlooked due in part to the state’s harsh winter conditions. Longer and hotter seasons could mean more successful vintages for Idaho winemakers.

“Unlike some other regions, Idaho has plentiful water and ideal growing conditions because of our warm summer days and cool nights,” said Moya Shatz Dolsby, executive director of the Idaho Wine Commission.

This temperature variance, called “diurnal shift,” helps to balance the wine by maintaining acidity. Coupled with Idaho’s position at 43 degrees latitude — the same placement as the famous Rhône Valley in France — the state becomes an enticing location for planting vineyards. As of 2017, the Idaho wine industry already represented $63.3 million in labor income and $209.6 million in business revenues, according to the IWC.

A vineyard perched on a hillside above Lewiston. Photo courtesy Idaho Wine Commission.

If temperatures continue to rise, U.S. winemakers will have no choice but to move their vineyards farther north. Grapes exposed to excessive heat can stop ripening, burn or develop a surplus of sugar come harvest time. The higher the sugar content, the higher the alcohol content, and the less balanced the wine.

These temperatures can also destroy the grapes’ malic acid — which gives them their tartness — and result in what’s known as “flabby” wine. Though the extreme heat hit California’s wine country first, if the trend continues, even regions as far north as Idaho will eventually feel these effects. Climate change, population growth and irrigation practices have already begun to take a toll on the state’s water supply, as discussed at the Governor’s Water Summit in August.

“The IWC is also supporting research at the University of Idaho to find soil amendments that will improve water retention and filtration in Idaho soils to aid vineyards,” Shatz Dolsby told the Reader. 

Idaho’s growing industry may tax the already declining water supply if steps aren’t taken to protect the state’s natural resources and the health of the soil.

Idaho is already home to more than 1,300 acres of vineyards, 75 wineries and three American Viticultural Areas: Snake River Valley AVA, Eagle Foothills AVA and the Lewis-Clark Valley AVA as far north as Lewiston. The oldest AVA in Idaho — Snake River — was only recognized in 2007, but it’s worth noting that the state’s history with winemaking goes back to 1864 and the first wineries in the Pacific Northwest.

“We do anticipate more AVAs in Idaho as our industry continues to grow,” said Shatz Dolsby. 

Consumers and fellow winemakers are paying more attention to Idaho as the state’s wines and vineyards fill the pages of top publications like Wine Enthusiast.

“Idaho wine is growing increasingly popular recently. While for the past few decades we’ve been written off as a place where great wine could never be produced, the Snake River Valley area specifically has started to prove that idea very wrong,” Barrel 33’s wine expert Ammon Ollerton told the Reader.

The local tasting room Barrel 33 specializes in regionally sourced wines with grapes grown either in-state or in eastern and central Washington. Most wineries in North Idaho use Washington grapes, given the proximity and limited supply in their home state — a fact that could change as Idaho establishes more AVAs and the existing ones develop a reputation for quality wine.

Including an AVA on a label indicates the wine’s quality and can lead to major price increases if a region becomes famous for a specific variety. Think Napa Valley Cabernet Sauvignon.

The U.S. Tax and Trade Bureau determines the boundaries of AVAs using weather patterns and geographic features that give the wines from that area distinctive characteristics.

These factors, when combined with the agricultural practices and soil types of specific vineyards, create terroir — a word that describes both the environment affecting the wine and the unique profile of the wine itself. Quality winemakers will almost always showcase the terroir on their labels, as the evocative descriptions give the wine a sense of place and help it sell.

“Making great wine comes naturally here. Literally. Mother Nature herself gifted Idaho with things like a diurnal shift and rich, diverse soils, which produce wildly flavorful grapes. Add in a passionate community of wine-loving experts and you get something truly spectacular,” said Shatz Dolsby, describing Idaho’s terroir and wine culture.

When you buy a good wine, you’re also buying into the image of the vineyard, therefore growers and winemakers take great care when making aesthetic choices about their brand. Idaho’s natural beauty easily feeds this fantasy, and that is why the IWC’s 2023 Tour Brochure speaks to the state’s “breathtaking wilderness” when showcasing the wines.

A bunch of Idaho-grown grapes. Photo courtesy Idaho Wine Commission.

Despite the potential benefits of warmer summers, wine grapes are still susceptible to the wildfire smoke that plagues the West Coast during fire season each year. Grapes exposed to the ash and hazardous air conditions develop “smoke taint” from volatile phenols and sulfurous compounds, affecting the smell and taste of the wine, according to Wine Australia.

Australian winemakers saw the effects of extreme levels of smoke when catastrophic bushfires ravaged the country from 2019-2020, and vineyards from California to Idaho now face similar hazardous air conditions each summer.

Wine Australia explains that tainted wine can taste like ash, disinfectant, smoked meat, leather or salami — nothing worth drinking. As with purified water, winemakers can use molecular reverse osmosis machines to filter out some contaminants; however, to many in the industry, altering wine on the molecular level borders on sacrilege.

The Associated Press reported Sept. 28 that scientists from Oregon State University, Washington State University and the University of California, Davis “are working together to meet the threat, including developing spray coatings to protect grapes, pinpointing the elusive compounds that create that nasty ashy taste, and deploying smoke sensors to vineyards to better understand smoke behavior.” 

As of yet, there’s no guaranteed method to salvage the tainted wine.

Idaho may benefit from warmer summers in the interim, but if left unchecked, fires and blistering temperatures will eventually destroy the U.S. wine industry.

“The smoke from the fires can also ruin grapes up to 100 miles away, making the wine they produce undrinkable,” Reuters reported in September 2022, citing a study published in Proceedings of the National Academy of Sciences, which indicated that should temperatures increase by 3.6 degrees Fahrenheit, “viable wine-growing regions could shrink by more than half.”

While the root cause remains, no amount of research or new protection measures can salvage the delicate flavors of well-crafted wine grown from a healthy planet.

The obvious solution is to combat climate change — if for no other reason than to ensure the privilege of drinking bad wine by choice, not necessity.