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It’s that time of the year to start preparing for license and certificate renewal season for pesticide applicators with the California Department of Pesticide Regulation (DPR). Applicators should have received their renewal notice in the mail (and if not, then please contact DPR at [email protected]).

In California, the Department of Pesticide Regulation (DPR) has a license and certification system which allows for professionals to apply pesticides as a part of their job duties. While everyone using pesticides must follow all directions on the pesticide label, as well as any additional state or local regulations, professional applicators need to follow additional regulations. Most employees who spray pesticides hold a qualified applicator license (QAL) or qualified applicator certificate (QAC).

Sharing a link to an article posted by the UC Davis Department of Plant Sciences recapping the 28 year career of Cooperative Extension Weed Scientist Dr. Steve Fennimore.

Here's a directly link to that article: https://www.plantsciences.ucdavis.edu/news/fennimore-retirement

Introduction

The California Weed Science Society (CWSS) publishes a twice-yearly "CWSS Research Update and News" newsletter as one of the society's publications.  The July 2025 issue just went online and is available here: https://cwss.org/wp-content/uploads/2025/07/CWSS_Research_Update-July-2025.pdf

My name is Mandeep Singh, and I’m honored to serve as the Agronomy Advisor for Sacramento, Solano, and Yolo counties, based at the UCCE Capitol Corridor office in Woodland. From an early age, I was involved in managing row crops like alfalfa, wheat, cotton, rice, sorghum, and oats, as well as caring for livestock on my family's farm. I did my bachelor’s and master’s degrees in agronomy from Punjab Agricultural University.

Branched broomrape (Phelipanche ramosa) is an invasive parasitic plant that poses a significant threat to California’s processing tomato industry. Known for its ability to attach to and draw nutrients from host roots, this pest can cause yield losses and trigger strict quarantine measures in California commercial fields. Building on Israel’s PICKIT approach for Egyptian broomrape (P. aegyptiaca), California researchers are working to adapt and refine chemigation-based herbicide strategies that target this challenging weed without harming tomato crops.

Branched broomrape (Phelipanche ramosa) continues to challenge California’s processing tomato industry, particularly in the Sacramento Valley. As a parasitic plant that attaches to tomato roots, its presence threatens both yield and export market access. In a recently published study in Weed Technology, we evaluated the efficacy of chemigated rimsulfuron—a recently registered approach with potential to offer targeted, soil-based suppression of this invasive pest.

Calibration might sound intimidating, but it’s critical for safe and effective herbicide application. Proper calibration ensures that the correct amount of pesticide is applied to an area while achieving the desired level of pest control. To support land managers and pesticide applicators, the UC Statewide Integrated Pest Management Program, in collaboration with the California Invasive Plant Council, has released a new online course: Herbicide Application Calibration for Non-Agricultural Sites.

This year in Southern California the rainy season got off to a late start. Southern California has received about one half of the average precipitation total as of this writing (and that's not an April fool's joke). Last year we had over 50% more rainfall than the historic average, it was a wet year. Most of inland Southern California receives about 12 inches of rainfall in an average year, this year we've had less than 6 inches and last year we had about 16 inches.