Sharpen your pencil, and take this quick quiz: The pest triangle is (a) an alarm you ring when you spot bugs in your customers’ corn; (b) a romantic conflict involving three bean leaf beetles; or (c) a set of factors that can help you and farmers determine whether an insect or disease is reaching problem levels.
The answer, of course, is (c). The triangle consists of the host, the pest and the environment.
Farm Journal Agronomist Ken Ferrie adopted the term “pest triangle” from “disease triangle,” a phrase that was coined by plant pathologists. Ferrie adapted it because the concept applies to insects as well as disease.
In most scenarios during the season, Ferrie says the pest must be present and the environment must allow it to reach a damaging level before treatment is justified. He likes to say, “If you don’t have the environmental conditions for a pest, it won’t be there.”
Pest prevention without evidence of a threat is not a sound basis for treating. That’s true now more than ever. With the way the financial picture is shaping up for everyone this season—along with the need to be ever-conscientious about stewardship practices—retailers need to make treatment recommendations to farmers based on boots-in-the-field scouting and sound economic returns.
As always, the types of insects and disease you find in farmers’ fields this year will depend a great deal on how Mother Nature behaves. Right now, much of the country is fairly dry and coming off a mild winter. Early-season insects could be more of an issue this year, and seedling diseases may be less of a problem. But hey, I’m writing this in late March, so this is speculation. April conditions will ultimately determine what you find out there.
Regardless of how the weather behaves, we all need to keep our eyes on the prize (strong yield outcomes) and be prepared. In the process, consider putting the pest triangle to work as you scout your customers’ fields.
Final Note. Make sure you give Managing Editor Margy Eckelkamp’s insightful story on citrus greening a read (page 10). The disease has ravaged the Florida citrus industry and now threatens California’s. The collaborative work between industry members in those two states is something we can all learn from.