This may be a year, the first in many, when cotton growers may not have to make as many, or any foliar insecticide applications for thrips. As of this week, we are just beginning to see movement of adult thrips into cotton. We have 3×5 inch yellow sticky cards placed into fields in 5 locations around our cotton growing area (one of those is just across the state line in Northampton County, NC). We are getting a few adult tobacco thrips, an occasional western flower thrips, and a lot of soybean thrips (which are not a serious problem in cotton). I think we are just at the beginning of the large third thrips generation that typically causes our problems. Thrips cause the biggest challenge to seedling cotton when it is cool and dry after emergence. Cool, dry conditions slow seedling growth exposing plants to thrips feeding for a longer period of time, and inhibit insecticide uptake creating the ‘perfect storm’. However this year, we have good soil moisture and a lot of cotton was planted in late April during the warm spell and is already pushing the 2-leaf stage. With one more rain and another week of warm weather, many fields will be out of danger, or at least at much lower risk to thrips damage. Once pants reach the 3-4 leaf stage, thrips feeding may cause some leaf crinkling, but the damage does not reduce yield. Thrips WILL invade cotton, and most likely in large numbers. But this year, if rains and warm weather continues, plants may be able to quickly outgrow the damage.
PS, we have been having some issues with this advisory, delivering multiple emails. The Southern Region IPM Center in Raleigh, NC hosts and services this advisory. They are doing what they can to clear up the problem. We are grateful to them for their continued support of our VA AG Pest Advisory.