Cristina Lazcano,* Kerri Steenwerth, Charlotte Decock, Mallika Nocco, Amelie Gaudin, Elisabeth Forrestel, Patricia Skinkis, Kristopher Covey, Mark Battany, Ellen Bruno, Corinne Butler, Connie T. F. Wong, Amanda Rodriguez, Axel Herrera, and Imane Slimani
*University of California – Davis, Department of Land, Air and Water Resources, Davis, CA, 95616 (clazcano@ucdavis.edu)

Aware of the importance of soils for climate change mitigation and consumer demands for sustainability, winegrape producers are seeking to increase soil health using regenerative agriculture (RA) practices. Soil health is directly associated with soil organic matter (SOM) and C contents, constituting a pathway for climate change mitigation. Increased SOM may also improve soil water holding capacity, helping with climate change adaptation. Increasing soil C stocks could be economically advantageous for growers, allowing them to participate in C markets and facilitating access to certifications. Nonetheless, several uncertainties exist regarding how to build up C and SOM in different soils and how this will affect the yield and quality of the grapes. With support from the Foundation for Food and Agriculture Research and the California Department of Food and Agriculture, a new project will determine the efficacy of RA in building soil C and soil health, improving the long-term environmental and economic resiliency of the winegrape industry. We will follow a multi-scale approach ranging from a high-density sampling of soil C within single vineyards to large-scale sampling across 100 vineyards and 12 controlled trials along an edaphoclimatic gradient from Oregon to California. This project will generate 1) a protocol with the minimum sampling intensity needed to estimate soil C stocks in a specific area accurately; 2) an estimate of the C abatement potential of RA in vineyards, positioning the grapegrowing industry in the rapidly growing landscape of C markets and incentive programs for climate mitigation; 3) site-specific best management practices for RA in winegrapes, including improved understanding of the impacts of livestock integration on vineyard soil health; 4) understanding of the effects of RA practices in vine yield and nutrition; 5) realistic targets and expectations of the benefits and cost of RA; and 6) educational materials for growers to measure soil health and understand its costs and benefits.

Funding Support: – Foundation for Food & Agriculture Research (FFAR) – California Department of Food and Agriculture (CDFA)