Bagrada bugs are definitely a major problem at the moment and are likely consuming a large portion of everyone's spray budget. However, don't forget about beet armyworms and cabbage loopers which are historically the most important pests of produce crops in September and October. Worm pressure has been light the past few fall growing seasons, but if populations showing up on fall melons and early produce thus far are any indication, it could be different this fall. Armyworms are especially abundant on all produce crops at the Yuma Ag Center, and loopers have been higher than normal on fall melons. Temperatures are likely driving much of this activity, particularly higher night time temps. For a review of management guidelines for lepidopterous larvae on produce crops please visit this link. However, with all the pyrethoids being applied to cole crops for bagrada bugs, cabbage looper pressure may actually be low this year. Remember, pyrethroids alone are not very effective against beet armyworms. Fortunately, there are a number of insecticides that can be applied as stand-alone products that provide effective residual control of both of these lepidopterous species (for more information see this link). It probably goes without saying though, that until we learn more about the bagrada bug and until their numbers significantly decline, it would be wise to include a pyrethroid with all your worm sprays this fall.

To contact John Palumbo go to: jpalumbo@ag.arizona.edu

For questions or comments on any of the topics please contact Marco Pena at the Yuma Agricultural Center.
College of Agriculture, The University of Arizona, Tucson, AZ.