David Owens, Extension Entomologist, owensd@udel.edu
Small Grains
Insect pest populations in small grains are very quiet right now. Natural enemies are present in most fields in good numbers to suppress aphids. Grass sawfly has been reported, but in very low numbers. As a reminder, grass sawfly thresholds are less than that of true armyworm. It is green, with prolegs on every abdominal segment.
Cereal leaf beetle populations have been very low the last several years. We have been scouting for cereal leaf beetle for the last few seasons to validate a degree day model for peak egg lay developed by Virginia Tech and NC State. Due to their low populations, we need your help with this project. Below is a google form, if you see cereal leaf beetle eggs or larvae, please consider letting us know via the form. Thanks! https://docs.google.com/forms/d/e/1FAIpQLSfXJimm0MNei91wfgU4wLEMHfOJu0s7r_f6LDPX51hhTmazEg/viewform?usp=sf_link
Corn and Soybeans
Planting has begun for corn and soybean. Scout for slug presence or injury, either by using a shelter trap or by sifting through soil residue. High risk fields include no-till, high residue fields. Vertical tillage before planting, row cleaners, trash wheels, and closed seed slots all help reduce slug damage. For corn, the decision to spread baits can be made after the corn has begun emergence, whereas for soybean, the decision-making is much more complicated.