Stink bugs are still an issue in some North Carolina cotton (see previous week’s article by Jack Bacheler), especially given the fact that we will have a late crop with late-developing bolls that will need protection. These are the results from an insecticide screening trial that I had this year. This was a situation under high pressure, so some of these chemicals might have been more effective in a different situation. The field was sprayed on the third and fourth week of bloom with the same insecticide in each plot. These results are from the 5th week of bloom. Remember that the treatment threshold in the 3-5 week of bloom is 10% injured bolls.
The primary stink bug species present in the field was brown stink bug, although there were a few greens. Brown stink bugs tend to be tolerant of pyrethroids. The two pyrethroids in this trial were Baythroid and Brigade. Brigade is bifenthrin, which we tend to set apart from other pyrethroids, due to the high amount of active ingredient present in most labeled rates compared to other pyrethroids (see this table for a comparison).