Salinity, water use, and drought tolerance took front row seats at this year’s annual Viticultural Research Roadshow in Fresno, Calif.

“Do we want to save our soils or save our water?” was the rhetorical question posed by Mark Battany, University of California (UC) viticulture and soils farm advisor with San Luis Obispo and Monterey counties.

The two are inextricably linked, he explains, inasmuch as water plays a role in moving salts out of the root zone. The use of well water high in salts contributes to soil salinity.

Battany studied salinity and its impact on grape vines in the Paso Robles area and found a steady increase in salinity from 2006-2012 which heightened soil electrical conductivity and reduced fruit yields.

Salinity can result from restricted drainage and no leaching of the root zone, he says. Even with occasional leaching, some salts can accumulate and impact vineyard performance.

Salinity can degrade soil structure and hamper nutrient availability. Battany’s research indicates each season of irrigation water applies about 775 pounds of sodium per acre and about 3.1 pounds of boron per acre.

Another viticulture roadshow speaker shared the importance to test soils and water, correct drainage problems, adjust water chemistry as needed, apply gypsum or acid as needed, leach with irrigation water when rainfall is insufficient, and use tolerant rootstock varieties.

Battany says gypsum helps displace sodium and counteracts bicarbonate.