Alternative weed management practices: Effects on weed control, grapevine performance, and soil quality in an established midwestern vineyard

Abstract

Sustainable grape production entails the implementation of management practices that control weeds, maintain grapevine performance, and conserve soil quality. Conventional weed management practices include herbicide application and/or cultivation. These practices compromise soil quality by limiting additions of organic matter and exposing the soil surface, thereby leaving it prone to degradative processes. With the expansion of continental climate viticulture in areas with rain-fed agriculture, such as in the Midwest, there is a need for sustainable weed management practices that optimize production while conserving soil quality. The primary objective of this investigation was to evaluate weed management practices in an established midwestern vineyard. Sub-objectives of the investigation addressed within individual experiments include: 1) comparing conventional and alternative weed management practices on weed control, grapevine performance, and soil quality, and 2) evaluating the influence of irrigation on grapevine growth and development, grown with and without a living mulch, on mitigation of water competition. An additional objective of this investigation was to survey Iowa fruit growers’ attitudes and awareness of weed management practices that conserve soil resources. In the first experiment, two conventional and two alternative weed management strategies were compared in an established Iowan vineyard with ‘Marechal Foch’ grapevines (Vitis rupestris Scheele ×vinifera L.). Treatments were replicated four times in a randomized complete block design and included: 1) cultivation, 2) herbicide application, 3) straw mulch, and 4) a living mulch of creeping red fescue (Festuca rubra L. ‘Pennlawn’). Straw and living mulches controlled weed populations and grapevine yield did not differ among the treatments. Dormant cane pruning weights and fruit quality were lowest in