Things are pretty quiet in cotton pest-wise, with the exception of scattered fields with spider mites and reports (mostly from northeast North Carolina) of pockets of plant bug activity.
We are not used to seeing spider mites in wet years and do not really understand the “why.” I have seen this in the past and have a couple of observations.
One is that under these conditions it is very hard to achieve perfect control of spider mites regardless of the products used, but, mite injury is not a great concern since plants are vigorously growing.
My recommendation is to hold off on treating unless 1) rainfall amounts decrease and we begin to see some drought stress, or 2) mite injury gets so bad that otherwise healthy leaves (mid- and upper-canopy) start to drop due to intense feeding.
Injury to and dropping of lower leaves is not really too concerning, as these lower leaves are not as important to overall plant health and will be shed in the natural maturing process.
We are not seeing much evidence of plant bugs in the fields we are checking, and not hearing about much from others.
We assess plant bug activity by checking for bugs and determining percent square retention. Plant bugs target squares and feeding results in shed.
The danger point is reached if retention drops below 80-85 percent — and the fields we have checked have greater than 90 percent retention.
At this point, most cotton in Virginia is into the flowering stage. Once flowering begins, we shift our emphasis to boll protection. We will follow with more specific advice in the next few weeks.
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