Early Season Plant Bug Management with Diamond

Most of the cotton across the Delta is squaring now and plant bug applications have started to go out on most fields.  We are catching a lot of plant bugs in flowering soybeans right now and the corn should start drying down in the next week or so. We are likely to start seeing a big migration of plant bugs moving into cotton from these corn and soybeans over the next couple of weeks. The following link, Early Season Diamond, shows the results from trials we conducted last year on grower farms across the Delta where we applied Diamond between the third week of squaring and first flower. In those trials, the average yields were 160 lbs higher in fields where we made one application of Diamond at 6 fl oz/A compared to fields where the Diamond was not used.  In small plot research, yield increases ranged from about 150 to 300 lbs per acre. In all of the trials, the applications targeted large numbers of adults migrating into fields before nymphs were present.  The impact of the Diamond at this time won’t be apparent until 10 days to 2 weeks after the application. Most of the adults that are migrating into cotton fields at this time have already mated and will be laying a lot of eggs. It is those eggs and small nymphs that the Diamond is controlling at this time of year and the benefits will be seen for a couple of weeks. This application won’t eliminate plant bugs and we will have to continue to make applications, but nymph numbers will be lower than they would have been without the Diamond, and spray intervals will likely increase from 4-5 days to 7-10 days. The key to this application is to get the Diamond in the field before large numbers of nymphs are present.