The Redbanded stink bug’s (RBSB) incursion into the upper reaches of the Midsouth is a relatively new occurrence. It is considered a more destructive stink bug pest than other stink bug species such as the green, southern green, and brown.
The RBSB does not go through diapause [a dormant or arrested development period] that enhances the hibernating potential of insects. In other words, this insect maintains year-round activity, and therefore must have a food source during the winter months in the Midsouth if it is not killed by cold temperatures [generally several hours at ≤23° F]. Since the RBSB feeds only on legumes, this means that any legume such as clovers and vetches that often grow on roadsides and ditch banks will provide an alternate food source during the winter months when soybeans are not available.
MSU entomologists, using “ditch bank” sampling that was conducted in the spring of 2017, were able to accurately predict the impending threat of RBSB that occurred in the 2017 soybean crop. During those samplings, they were commonly finding fairly high numbers of RBSB in crimson clover well north Highway 82, which roughly bisects the state. They also documented reproduction of the insect as early as March 2017. They surmised that these ditch bank samples were a strong indicator of the potential threat to the state’s soybean crop that would occur from RBSB infestations, which did in fact occur in 2017. This led to future surveys of likely overwintering habitats for this insect in order to predict what their growing season numbers might be since RBSB moves into soybean from legumes where it overwinters.
A Jan. 20, 2018 post on the MCS blog site offers perspective about how winter temperatures may affect RBSB populations that would be available to infest a subsequent soybean crop. MSU Entomologists Drs. Catchot, Cook, and Gore used the harsh temperatures in the winter season of 2017-2018 as an opportunity to instrument protected hiding places that were known to be inhabited by RBSB. This allowed them to monitor ambient temperatures for extended periods to determine the length of time that temperatures in these habitats were below the 23°threshold known to kill the RBSB.
Ditch bank surveys were restarted in early spring of 2022. Articles posted on the MCS blog site by Dr. Whitney Crow, MSU Ext. Entomologist, provide information about the dates of sampling, location of samples, and presence or absence of this insect at sampled locations. As of this writing, results from ditch bank survey samples through Apr. 22, 2022 are posted on the MCS blog site. Results thus far indicate that RBSB is present in several counties that are south of Hwy. 82 and one county that straddles Hwy. 82. However, as the season progresses, it is likely that they will be present in more northern parts of the state.
It is common knowledge that later-planted soybeans are more susceptible to damaging infestations by insects, including the RBSB. This could be especially problematic in 2022 since current soybean planting progress (24%) in Miss. is below the 5-year average of 34% according to NASS. Mississippi soybean producers are encouraged to access the MCS blog site for future survey results to ensure their awareness of the RBSB’s potential presence in their area.
Click here to access the 2022 Mississippi Insect Control Guide for current control recommendations for this insect (p. 42-43). Click here to access the Aug. 5, 2017 MCS blog post by MSU researchers/extension specialists that contains information pertaining to insecticides that can be applied to prevent this insect pest from damaging developing soybean seed late into the season. Click here to access a White Paper on this website that provides a detailed discussion about RBSB.
Composed by Larry G. Heatherly, Apr. 2022, email@example.com