High Numbers of Stink Bugs Showing Up in Some Mississippi Wheat Fields

We are beginning to see stink bugs show up in some wheat fields in the delta. It is not uncommon to find stink bugs in wheat after head emergence.  However, it takes extremely high numbers to cause economic damage to heading wheat.  With this in mind, seeing high numbers of stink bugs while walking a wheat field may seem alarming, but it takes a lot of stink bugs to cause economic damage.  Research from the early 80’s showed that the milk stage of development is most susceptible to damage from stink bugs by reducing grain weight and germination.  Current stink bug thresholds for wheat are 1 stinkbug/5-10 heads in the milk and soft dough stage.  Once wheat reaches the hard dough stage the likelihood of damage from stink bug is diminished greatly.  At this time the predominant stink bugs being found in Mississippi are rice and brown stink bugs.  Because we do not generally treat a lot of wheat for stink bugs, wheat can actually harbor lots of stink bugs that will eventually move out into corn and group four soybeans when the wheat begins to hit hard dough.  I have had several reports this week of stink bugs that are at and above threshold levels on field borders but populations tend to be lower away from field edges.  Be sure and scout adjacent corn fields closely for sting bugs.