Prevent Insect Pressure with Vigilant Scouting

September 3, 2021

November means the end of the growing season with harvest right around the corner. However, soybean fields still are at risk to some insect pressure that we should be scouting for, especially in food-grade beans. 

Grasshoppers, bean leaf beetles and stink bugs can still damage soybeans until they are nearly mature. Grasshoppers and bean leaf beetles will eat the pods and the grain in them, while stink bugs will piece the pod and suck the moisture out of the individual beans resulting in shriveled, off-color and generally unmarketable grain. 

The fields that are the most at risk are those that stay green the longest, such as late maturities and late-planted fields, as these fields will attract the pests from other maturing fields. Scout these fields first, making sure that you are off the headlands, and then inspect the pods for feeding from grasshoppers and beetles, also looking for the pests themselves. 

Stink bug scouting requires finding the bugs in the field: use a sweep net and do ten sweeps in multiple locations in the field. If the average of those sweeps is 2 stink bugs in food-grade beans or 4 in commodity beans, then an insecticide is warranted. 

If your fields are above threshold for any of these pests make sure to contact your retail supplier to get insecticide and get those sprayed, consulting the label for preharvest restrictions. 

An example of what insect feeding can do to grain quality. Be sure to scout you late maturing and food grade beans.