As farmers begin planting I started to think about early season insect pressure. I know most have moved out of corn and are getting ready to plant peanut. (Some have started already) But before you know it cotton planting will be upon us. The earlier you plant the higher the risk for issues with thrips. In peanut we see increased tomato spotted wilt as a result of the movement of thrips through the field. In cotton damage happens to seedlings as the cotyledon leaves are opening. Excessive thrips feeding results in crinkled malformed true leaves, stunted plants, delayed maturity, reduced yield potential, and in severe cases loss of apical dominance and stand loss.
If you use a seed treatment with insecticide or put insecticide in-furrow you may not need to do anything further. But in years where thrips numbers are high and early planting may mean seedling cotton is not growing as quickly; scouting is necessary to ensure fields are not affected. Foliar insecticides are recommended when 2-3 thrips per plant are counted and immatures (crème colored and wingless) are present. From emergence through the 4th leaf stage cotton is susceptible to damage.
North Carolina has developed a Predictor Tool that can give you an idea of what you are dealing with at planting time. Select your location in the white box on the map then add your planting date. Allow the computer to calculate and it will give you a graph showing historical data and a prediction for this year. At the bottom you will see the prediction for your location for the month.
It’s not exact but it will give you another tool to use in planning. If you know your risk is high you can plan to include something in furrow and scout to make an early post application for thrips in cotton. Early planted, conventional tillage fields are at the greatest risk for thrips damage.