Broomrape Concerns California Tomato Industry

Brian GermanFruits & Vegetables, Pest Update

A broomrape species has been causing some concern for California tomato growers after the discovery of Branched broomrape in a 70-acre field north of Woodland.  The weed was initially found four months ago which resulted in a quarantine and decontamination of the field with a crop duster.

“Our broomrape problem appears to be very isolated and limited. We hope to limit the spread, so this parasitic weed doesn’t become widespread and thus more costly,” said Gene Miyao, UC Farm Advisor for Yolo, Solano and Sacramento counties.

Nothing was harvested in the quarantine zone after all plant life was destroyed, reducing the risk of spreading the weed further.  The field was beyond the point of preventative measures, but that will be the approach for other growers moving forward.  “Prevention is helping to contain the spread by limiting movement from these fields, which would include cleaning equipment before moving from field to field,” Miyao said.

The parasitic plant species will attach itself to the roots of another plant and will be only visible when it flowers above ground.  Branched broomrape can remain in the soil for up to 50 years, and detection can be especially difficult with small infestations.

Another broomrape species was an issue for growers in Solano County three years ago when Egyptian broomrape was discovered for the first time in North America.  The California Department of Food and Agriculture, along with multiple industry stakeholders worked together in their eradication efforts. “The economic logic was to limit spread after an early detection by elimination which included fumigation,” said Miyao.