Redbanded Stink Bug Update 7/15/2017

We have sprayed several fields in the last 2 weeks for RBSB’s. To date, most fields have been late March planted beans that are R5.5-R6 growth stage. Most of the fields so far have been south of Hwy 82, but not all of them. Stink bugs are seed feeders. They preferentially want to be in beans that are filling pods. You will occasionally see them in beans that are not filling pods, but often times these bugs tend to move in and out of fields a lot at that time looking for more suitable host. This may explain why many of you have reported finding stink bugs in R2-R3 beans one week then gone the next. One thing is for sure, when seed starts filling pods, they want to be there, especially RBSB.  Currently, we are getting reports of 1-3X thresholds (4/25 sweeps) moving into fields approaching R6 rather suddenly. On these early planted beans that are at threshold, we may or may not have multiple sprays. It will depend on how many more are out there to re-infest the fields. Where we really anticipate the issues are in 3-4 weeks on the later planted beans when the bulk of our April planted beans is maturing and we see mass movement to the greener bean. This will likely result in repeated infestations.

We need to watch these field close and not delay if treatment is needed. As we have mentioned numerous times before, this stink bug is not the same as our traditional Southern Green, Green, and Brown. It is much more damaging and re-infest behind treatment much more quickly. As an example, we have been doing some seed damage surveys in a few fields where they have moved into recently:

Field 1. Population averaging 8-10/25 sweeps for about 10 days. Percent seed damage = 18.5%

Field 2. Population averaging 10-12/25 sweeps for about 10 days. Percent seed damage = 34.6%

Field 3. Population averaging 3-4/25 sweeps for about 14 days. Percent seed damage = 14.1%

We are seeing 70% of the damage in the top 50% of the plant. We have applied various treatments to these fields and plan to continue to monitor this and report results.

This is not a bug to play with. If you need to treat do not delay 5-7 days. Remember that this only applies to RBSB. You will not see this level of damage with the other species. Our favorite treatment is still Orthene + Bifenthrin (either .5 lb + 1:30 on low pops or .75 lb + 1:20 on high pops). We do like Belay + Bifenthrin as well (4 oz. + 1:20). Endigo looked good in a recent trial at 4.5 oz. as well. At 7 days after treatment straight bifenthrin at 1:20 (6.4 oz.) was 65% control. Karate at 1:65 (1.92 oz.) was only 50%.