Redbanded Stink Bug and Cover Crops

In this article, I will expound on one of the points covered in a presentation made at the Aug. 2017 Emergency Forum on Redbanded Stink Bug [RBSB]. All of the presentations made at the Forum can be found here.

In his presentation, Dr. Jeff Davis, LSU Assoc. Professor, made a point about the RBSB only feeding on legumes. Also, he stated that the RBSB, unlike many other insect species common to the Midsouth, does not go through diapause; i.e., this insect does not go through a dormant or arrested development period. In other words, this insect maintains activity year-round 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 deg. F].

Since the RBSB feeds only on legumes, this means that any legume such as clovers, peas, and vetches that are often used as components of a winter cover crop will provide an alternate food source during the winter months when soybeans are not available. Thus, the touted use of cover crops in a soybean production system (either monocropped or rotated) will provide a habitat for the overwintering RBSB if the cover crop contains a legume.

So here are some guidelines for using cover crops in a soybean production system when RBSB has been or may be present.

•   Monitor soybean fields for the presence of RBSB, and make/keep a record of infested fields.

•   In infested soybean fields, control/eradicate adult RBSB populations up to harvest to prevent their movement out of the infested field and to reduce overwintering populations.

•   If cover crops are to be planted following soybean harvest in monocropped soybean fields, do not include legume species in the cover crop mix if the fields have a history of RBSB presence.

•   In a biennial corn-soybean rotation system, plant a cover crop that contains a legume species only after the soybean crop since corn, which is a non-host, will follow the cover crop. It also will be a good idea to control/eradicate an overwintering RBSB population in this cover crop to prevent RBSB infestations in soybean fields that may be in close proximity the following summer.

•   When a cover crop mix does contain a legume species, monitor the stand for RBSB so that the overwintering population can be controlled/eradicated if necessary.

There is no doubt that cover crops can provide benefit in agricultural settings, but their species makeup must take into account how they will affect/promote damaging insect populations such as the RBSB.

Composed by Larry G. Heatherly, Aug. 2017, larryheatherly@bellsouth.net