Illinois soybean growers were warned Thursday about "suspicious-looking stink bugs" showing up in fields in the state.  The pest resembles the red-shouldered stink bug and was seen south of Champaign, Illinois. On Thursday, the sighting remained unconfimed, because the actual specimen was unavailable for examination.

Extension entomologist Mike Gray advised growers to be "vigilant in scouting fields and to report any stink bug species that resemble the red-shouldered, red-banded or brown-marmorated stink bugs."

Green and  brown stink bug species are attracted to soybeans in the bloom to early pod-fill stages and can cause significant damage to plants, according to the release from the University of Illinois.

“Because of their ability to damage tender plant tissues, especially developing seeds, they are capable of causing economic losses to soybean producers,” Gray said. “The economic threshold of one bug per row foot during the pod-fill stage has been suggested.”

Stink bugs have become a growing problem in the Southeast, including including in Arkansas, Louisiana, Mississippi, Missouri and Tennessee, the Illinois report said. 

Last week, Michael Marlow, a Texas agronomist reported that stink bugs were "moving across central Texas and into Oklahoma cotton and soybean crops." He advised producers to scout and consider treatment.

Other recent reports on stink bugs in soybeans have come eastern states, including Maryland and Pennsylvania.

“The red-banded stink bug has caused significant management challenges, particularly in Louisiana where densities of the pest have reached economic levels,” Gray said. “The suggested economic threshold for the red-banded stink bug is 24 insects per 100 sweeps as compared to 36 insects per 100 sweeps for the brown stink bug.”