California has abundant wildlands—forests, rangeland, open areas, wildlife refuges and national, state, and local parks—that need protection from invasive plants. Invasive plants affect all Californians by increasing wildfire potential; reducing water resources; accelerating erosion and flooding; threatening wildlife; degrading range, crop and timberland; and diminishing outdoor recreation opportunities. According to the California Invasive Plant Council (Cal-IPC), more than 200 identified plant species harm California’s wildlands.

Cal-IPC and UC IPM’s Cheryl Wilen, Tom Getts, Tunyalee Martin, and Chinh Lam, with funding from the California Department of Pesticide Regulation (DPR) Alliance Grants Program, developed two resources that provide land managers access to the latest information on nonherbicide practices for managing weeds in wildlands. Best Management Practices for Non-Chemical Weed Control is a free downloadable manual. The same information has been incorporated into an interactive online tool called WeedCUT (Weed Control User Tool: weedcut.ipm.ucanr.edu).

Best Management Practices for Non-Chemical Weed Control provides comprehensive descriptions of 21 commonly used nonherbicide weed control techniques and biological control agents for 18 invasive plant species. Each chapter is the synthesis of research outcomes and on-the-ground knowledge from practitioners about nonherbicide methods. The chapters describe how a technique is best applied, the types of invasive plants and environmental conditions where it is most effective, and what its shortfalls might be. Environmental, cultural, and human safety risks are highlighted to help support the safe and effective use of these methods.

WeedCUT is the online version and can be used to learn about the different nonherbicide management methods, including the section on biological control. To filter through the database and learn which management practice to consider for a particular site and invasive plant type, a simple interface allows users to pick characteristics that describe their site and invasive plant problem. The tool then filters through the database to display the practices ranked by efficacy (excellent, good, fair, poor, or ineffective). As in the manual, use of the technique and potential hazards are covered.

Best Management Practices for Non-Chemical Weed Control and WeedCUT are designed to be the go-to resources for practitioners that complement their conventional weed management work with nonherbicide techniques or are restricted in their use of herbicides. Both resources will help practitioners manage weeds more effectively.

“Many experts in the field have contributed to creating the manual and WeedCUT. It has been exciting to see these techniques described and reviewed so carefully. We’re looking forward to seeing land managers, as well as all folks fighting weeds, incorporating the information from the manual and WeedCUT into their work,” says Jutta Burger, science program director and project lead with Cal-IPC.

Emeritus Area IPM Advisor Cheryl Wilen with UC IPM says, “We anticipate that using WeedCUT will increase the use of mechanical, physical, or biological practices, and potentially result in the reduction of herbicides used to manage wildland invasive weeds. Best Management Practices for Non-Chemical Weed Control and WeedCUT were developed so land managers can become more knowledgeable and skilled in the use of nonherbicide methods as part of an IPM program.”

While the manual and tool focus on nonherbicide methods, the hope is future funding can be found to continue the work and integrate herbicide options online. “Land managers typically use both herbicide and nonherbicide methods, alone and in combination, to manage invasive plants in wildlands. A tool that combined both herbicide and nonherbicide methods would guide land managers to determine the most effective overall management program for their particular site,” says UC Cooperative Extension Advisor and UC IPM Affiliated Advisor Tom Getts.

Martin TA, Burger J, Wilen CA, Getts T. 2021. UC launches WeedCUT, a new online tool to manage invasive weeds in wildlands without herbicides. UC ANR Green Blog. https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=48886