Scouting, Mapping, and Reporting Broomrape

Purpose

This page explains when to scout, where to look, what to record, and when to report suspect broomrape plants so operations can respond quickly and consistently.

Required Under the Current Compliance Agreement

High-Risk Fields

Field personnel and contractors authorized to enter high-risk fields must be trained to recognize broomrape and to follow the applicable sanitation guidelines. High-risk fields must also use the Board-recommended growing degree day model to develop a scouting and rogueing plan, keeping a record of when these actions took place. The exact location of the first suspect broomrape plants found during the season must be reported immediately to the contracted processor, and to the Program as well if the detection is outside the Designated Zone.

Low-Risk Fields

Field personnel in low-risk fields must be trained to recognize broomrape and to follow the applicable sanitation guidelines. The contracted processor must be notified immediately when a suspect broomrape plant is detected so that the field can be converted from a G2 to a G1, and the Program must also be notified if the detection is outside the Designated Zone.

What Current UC Work Supports

Current UC guidance indicates that broomrape emergence often begins around 400 growing degree days after transplanting. The linked growing degree day tool is intended to make that timing practical by using transplant date and field location to estimate windows for chemigation, scouting, and rogueing. UC guidance also supports early detection and response, because early-stage infestations provide the best opportunity to remove suspect plants before they drop seed and increase the total seedbank. In the Designated Zone, scouting should not be limited only to fields with known prior detections.

UC Recommended Practices

For All Tomato Fields in the Designated Zone

Use the growing degree day tool to set likely scouting windows based on transplant date and field location. Give added attention to field edges, entry points, prior detection areas, repeated cleaning locations, and other places where equipment or workers move in and out frequently.

When a suspect plant is found, record the location in a form that the operation can use again. A map pin, GPS note, or marked field map is usually sufficient if it allows the operation to return to the same location quickly. At a minimum, record the field name or number, the date, who found the plant, the approximate row or bed location, and whether the detection was near an entry point, prior hotspot, or repeated cleaning area.

Additional Notes for High-Risk Fields

In high-risk fields, scouting should follow the operation’s formal scouting and rogueing plan. The goal is to find suspect broomrape early enough to report it, remove it, and reduce further seedbank buildup. Suspect plants should then be handled according to the linked rogueing and disposal guidance.

Additional Notes for Low-Risk Fields

Remember that low-risk is not the same as no-risk. In low-risk fields, scouting still matters because a new detection, particularly outside of the designated zone, allows for more rapid response while there’s still time to minimize the infestation. If a suspect broomrape plant is found, reporting should happen immediately and the operation should be prepared to shift from routine monitoring to a more active response before the infestation is well established.