Optimizing spider mite management through biological control in walnuts and vineyards
The web-spinning spider mite (Tetranychus spp. and Eotetranychus willamettei) is a pest that causes severe leaf drop and reduced photosynthesis and plant growth. Walnut and winegrape growers routinely struggle with spider mite management, but have limited low-risk effective options. Furthermore, dependence on limited chemical options is of particular concern for spider mites as they can rapidly develop resistance to pesticides. These factors increase the need for alternative management practices that focus on biological control, such as:
In partnership with CDFA, UC Cooperative Extension, Pest Control Advisors (PCAs), and commodity boards, this project will implement research trials on eight farms in the Sacramento and San Joaquin Valley to investigate the efficacy and cost comparison of these three practices. Over two seasons, the Ecological Pest Management (EPM) team will monitor for web-spinning spider mite and its natural enemies. In addition to this research, the EPM team will provide technical assistance and robust outreach and extension to promote knowledge-sharing about these biological control practices.