Final Report: This is a completed project for the Washington Grape & Wine Research Program
Date: 29 June 2018

Project Title: Assessing and Ameliorating Salinity and Sodicity in Eastern Washington Wine Grape Vineyards
Project Duration: July 2016 – June 2018

PI Name: Joan R Davenport
Organization: Washington State University
Address: 24106 N Bunn Road, Prosser, WA 99350
Telephone: 509-786-9384
Email: jdavenp@wsu.edu

Co-PI Name: Michelle Moyer
Organization: Washington State University
Address: 24106 N Bunn Road, Prosser, WA 99350
Telephone: 509-786-9234
Email: michelle.moyer@wsu.edu

Co-PI Name: Troy Peters
Organization: Washington State University
Address: 24106 N Bunn Road, Prosser, WA 99350
Telephone: 509-786-2226
Email: troy.peters@wsu.edu

Cooperator Names: [too many to list]
Description of Participation: Vineyard blocks and water sources for sampling

Project Summary:

Grapes are classified as moderately sensitive to salt (Maas, 1986). Saline and sodic soils can occur naturally in the irrigated wine grape production areas of Washington State; however, vineyards typically are not established in low-lying sites that are risk for additional salt accumulation. Many vineyards are either partially or entirely irrigated from groundwater sources. Most deep wells in central Washington growing regions contain high concentrations of carbonates and bicarbonates and may also be high in sodium, depending on the chemistry of the groundwater.

Long term use of low-quality water leads to soil degradation, as soils become either saline (a nonsodic soil containing sufficient soluble salts to adversely affect the growth of most crop plants), sodic (a nonsaline soil containing sufficient exchangeable sodium to adversely affect crop production and soil structure under most conditions of soil and plant type), or both saline/sodic. Growers have increasingly brought in soil sample results or requested help with struggling vineyards, where the test results clearly indicate that the soils are saline and/or sodic (>1.5 dS/m or > 13 % ESP [Exchangeable Sodium Percent]) (US Salinity Laboratory Staff, 1953).

While soil salinity and/or sodicity is not limited to wine grapes, use of deficit irrigation in vineyards can accelerate the development of the problem. Additionally, growers may increase deep well groundwater use in drought conditions when irrigation district water sources are limited (e.g., 2001 drought).

Grapevine response to soil salinity and sodicity have been studied (Bramley et al, 2011; Suarez, unpublished data). Remediation strategies have been identified, but may be limited in their adoption in Washington due to the specificity of location from which they were developed. The goals of this proposed research are to first gain an understanding of the degree of affected eastern Washington vineyards and then to evaluate potential techniques that effectively remediate/ameliorate soil salinity and/or sodicity.

Project Major Accomplishments:

Objective 1: Survey vineyards and water sources for degree of salinity and/or sodicity in south central Washington (including but not limited to the following AVAs: Yakima Valley, Horse Heaven Hills, Red Mountain, Columbia Valley, and any AVAs contained within these).

Procedures:

Objective 1 takes a survey approach to determine the range of effects from using impaired water sources on vineyards in south central Washington. Vineyard sites were identified based on knowledge of growers who have expressed concerns in the past through sharing results of soil and or water tests. Bulk soil and irrigation water samples were collected from vineyards in fall 2016 and 2017 as well as spring 2017 and 2018 to see seasonal fluctuations as well as to look for consistency or changes with time.

Read more by downloading the full report above.

Irrigation // Viticulture //