Ferrington Vineyard Field Trial

Norman Kobler, manager and co-owner of Ferrington Vineyards, was one of the first to participate in the North Coast Soil Health Hub. He has participated in a suite of soil health-related projects including a demonstration site, ongoing field trials, and soil health assessments, and he has a Carbon Farm Plan for the site. A local, multigenerational grapegrower, he finds value in continuing to experiment with how to further enhance his vineyard’s high-quality grapes, water use efficiency, ecosystem resiliency, and overall sustainability. About half of the 167-acre property is vineyards, while the other half remains as oak-grassland hillsides grazed by sheep. These sheep make their way into the vineyards too, helping manage the cover crops.

With his early interest in soil health, Norman helped the local USDA Natural Resources Conservation Service office to set up a replicated field trial investigating the effects of several common cover crop and tillage management approaches on soil health and vine growth. He has maintained the trial since 2015, and it has become a demonstration site for the North Coast Soil Health Hub. The trial is located near Boonville, CA on the valley floor of Anderson Valley, and the site’s soil is Boontling loam. The trial includes five cover crop and tillage combinations: no-till with a reseeding annual cover crop, till with a biomass, green manure cover crop, an alternate row system with the preceding two managements, and no-till with naturalized vegetation.  Starting in the spring of 2017, a tilled treatment with no cover crop planted was established on half of each of the plots with no-till and naturalized vegetation.

Ferrington’s Carbon Farm Plan estimates that the property is capable of reducing approximately 18,434 metric tons (MT) of CO2 equivalents over 20 years, 7,074 MT through the continuation of existing climate beneficial practices such as cover cropping, prescribed grazing, and preserving riparian forest buffers and 11,360 MT more by adding practices like composting and mulching. This equates to removing about 3,983 passenger cars from the road for a year.