Cotton is coming up now and we are seeing first true leaves. I did a count for thrips yesterday and found them to be over threshold. This is an area in the county which is notorious for having high thrips populations. I was finding both mature and immature thrips which warrant a spray, and also thrip numbers of 3-4 per plant also warrants a spray.
We were also noting some herbicide damage with rain at germination. One thing we are finding is cotyledons cupping. Cupping of the leaves is evident of thrips damage – we are seeing this with true leaves and cotyledons. However, UGA Extension Entomologist, Dr. Phillip Roberts, says cupping on the cotyledons is NOT from thrips injury. The only thrips injury we would observe on cotyledons is silvering on the underside of cotyledons where the thrips were feeding, not mishapen cotyledons. That would differentiate some herbicide injury. Nonetheless, a thrip spray would lessen some stress on the plant.