New Early-Season Soybean Pest Emerges

Clipped or missing plants could be a sign there’s a new scavenger in your emerging soybean fields, according to a recent article in Wallaces Farmer.  Isopods – a.k.a. woodlice, pillbugs, sowbugs and roly-polies – are a new early-season soybean pest in the Midwest.

No-till fields can be especially attractive to isopods as the crop residue helps provide high levels of moisture needed for their survival. Because all life stages breathe through gills, isopods must live in habitats with high humidity.

These omnivores scavenge on dead and decaying plant or animal matter but will also eat live, young plants. Feeding is often done at night as isopods are skittish.

Although small in size (adults are three-eights inches long), isopods can do big damage.  Some areas in Kansas and Nebraska have already experienced economically damaging levels of isopods that required replanting.

Management is difficult as these terrestrial crustaceans are naturally protected by armor-like plates on their backs.  Seed treatments and foliar insecticides have been ineffective. To minimize overwintering populations and to reduce soil moisture in the spring, Extension crop specialists are recommending to till heavily infested areas every other year.  Click here for more information, including photos of affected seeds and seedlings.