Although pressure is currently below average, it is increasing, which is to be expected as we enter the early blooming window. We have limited but good options to control plant bugs in blooming cotton. I often tell folks that if you call me once bloom starts, I’ll often only mention 4-5 products, sometimes in combination. Those include Acephate/Orthene, Diamond, Transform, and Bidrin. Vydate also gets and honorable mention. These are the core products suggested for mid-season plant bug control. Below are some treatment options I like, in no particular order. However, I’d like everyone to get Diamond and/or Transform into the mix. Not only because they work well, but also because they have a different mode of action and help with resistance management. Once we get into the peak bloom window, many of my recommendation are intended to control plant bugs and stink bug, as stink bugs generally get more problematic as more bolls are present.
Below, I’ve rated rainfastness as poor, decent, and good. I base this on a rain event occurring within a few hours after an application. However, with the exception of acephate, I would not automatically retreat a field if it rained two or more hours after application. I’d wait until the next scouting period to assess performance as the insecticide will have provided enough control to buy you some time.
- Acephate/Orthene at ¾ – 1 lb/acre … good all-around choice for stink bugs and plant bugs … poor rainfastness and re-treatment may be needed if rain occurs with 4 hours of application.
- Transform at 1.5 – 2 oz/acre … good on plant bugs, weak on stink bugs, unlikely to flare spider mites, and controls aphids … decent rainfastness
- Bidrin at 6 – 8 oz/acre … not quite as good as acephate on plant bugs but a little better on stink bugs … decent rainfastness
- Diamond at 4 – 6 oz/acre and usually co-applied with Orthene (0.5 lb), Bidrin (4 – 6 oz), or Transform (1 – 1.25 oz) … Diamond has good rainfastness and is good on plant bugs … Diamond alone is generally poor on stink bugs and will not control adult plant bugs or stink bugs (hence the mix)
- Transform at 1 oz/acre and co-applied Acephate (0.5 lb) or Bidrin (4 oz) … good plant bug control and better stink bug control than Transform alone … you could consider mixing with a pyrethroid like Bifenthrin/Brigade, but I would avoid this mix if plant bugs are the primary target
Rates are important, but I’ve not seen much advantage to using rates higher than those above. It’s harder to save an application by using a higher rate than it is to add an application by choosing the wrong product or too low a rate.