Alfalfa insect management survey & insecticide resistance screening
If you have found yourself dealing with alfalfa weevil more often in the last few years, you are not alone. Reports of large populations and control failures have seemingly increased in recent years, not just in Illinois but throughout the Midwest. Alfalfa weevil populations resistant to pyrethroid insecticides were confirmed in the western U.S. several years ago, and there are some indications we might be seeing this in the Midwest as well. In Illinois specifically, it has been several years since our management recommendations in alfalfa have been revisited – we want to make sure these recommendations reflect the current situation. With that in mind, we have two opportunities to help guide future management efforts:
My colleagues at University of Minnesota Extension are coordinating a multi-state survey to assess current management practices and challenges related to alfalfa insects, in particular the alfalfa weevil. If you farm, consult, or are otherwise involved in alfalfa production, please consider participating in this survey at the following link: https://z.umn.edu/alfalfapestsurvey. Through this survey, we are hoping to better understand how often insect pests are impacting alfalfa, how effective our controls are, and what pest management issues you would like to see addressed related to alfalfa production.
Later this spring, we will be subjecting alfalfa weevils to insecticide resistance screening following methods that were used to confirm pyrethroid resistance in the western U.S. If you have experienced control failures in the past and would not mind us taking some alfalfa weevil larvae off your hands this spring, please reach out with your rough location and the nature of your past problems (preferably with an email to nseiter@illinois.edu, with “alfalfa weevil” in the subject line). While we might not be able to assess every population we hear about, we hope to assess several throughout the state and get a feel for the variability.
You will hear more about these projects as they progress. If you are interested in either, please do not hesitate to reach out.
Nick Seiter, Field Crop Entomologist | nseiter@illinois.edu | 812-593-4317