Some phone calls and some personal observations indicate that tarnished plant bugs are getting more common … not blow out but building. This is not surprising as the crop begins to grow. In cotton approaching bloom, this would be the time to consider applying 4-6 oz of Diamond if threshold levels of adults are found in fields. Remember that a tank-mix partner to control adults is generally needed with applications of Diamond. Prior to bloom, I would normally suggest mixing Centric or the highest labeled rate of one of the imidacloprid products (Admire Pro, Alias, etc.). Orthene/Acephate, Vydate or Dimethoate are tank-mix options, although I generally prefer to reserve the use of OP insecticides like acephate until after first bloom for resistance management reasons. Bidrin can be used as a tank-mix partner if the cotton is blooming (but not before).
Transform is another option. Consider starting with the options above and use Transform on follow-up applications when immature plant bugs begin rebuilding. The standard rate is 1.5 oz/acre. Using Diamond and Transform in sequence gives us two unique modes of action. Of course, as the season progresses, everything is in play but the need for tank mixes will become more necessary as stink bugs and bollworms begin to make their appearance later in the month. Let’s cross that bridge when we get there!
Reminder: Too many people try to throw everything into one application against plant bugs in hopes they won’t have to respray. It is true that the best treatments can often prevent or delay the need to retreat. However, this only goes so far. Two applications with a good treatment will be better than one application, regardless of what you spray. In other words, spending $10 twice will almost always be better than $20 once in terms of insect control and crop protection. As a group in the Mid South, entomologist have gone to the effort to ranking insecticide efficacy for many pests. There’s more to picking an insecticide than just its efficacy on one pest. Often there are multiple pests in the field, label restrictions, and resistance management considerations. However, the charts linked below are a helpful starting place.