At our cotton meeting, UGA Extension Entomologist Dr. Phillip Roberts talked about a new model to help predict thrips infestation. The Thrips Infestation Predictor for Cotton tool can be found at http://climate.ncsu.edu/cottonthripsrisk/ . Dr. Roberts has this to say about the model and scouting:
Thrips are the most consistent insect pest of cotton in Georgia and the southeast. Near 100 percent of the cotton planted in Georgia will be infested by thrips each year. Preventive insecticides applied as a seed treatment and/or infurrow application at planting for thrips control provide consistent yield responses. In some situations supplemental foliar insecticides may be needed in addition to preventive treatments at planting.
Plant injury from thrips is a function of thrips pressure and seedling growth. The Thrips Infestation Predictor for Cotton (TIP) tool uses planting date, temperature, precipitation, and knowledge of when and how intense thrips infestations will be to predict risk of thrips injury to cotton. The TIP model can be used to identify planting dates which are at greatest risk for thrips injury. The TIP tool will give the best predictions within 10-14 days after you use it, so use at multiple times during the planting and thrips management season would be beneficial. Dr. George Kennedy has prepared the webinar “Thrips Infestation Predictor for Cotton: An Online Tool for Informed Thrips Managment”. The webinar includes an overview and how to use the TIP tool and can be found at http://www.plantmanagementnetwork.org/edcenter/seminars/cotton/ThripsInfestationPredictor/
High risk planting dates will require more aggressive thrips management compared with low risk planting dates to achieve acceptable thrips control. Management options for high risk planting dates would include the use of infurrow liquid insecticides such as acephate, imidacloprid, or aldicarb or the use of a neonicotinoid seed treatment plus a supplemental foliar application at the 1-leaf stage. In low thrips risk environments neonicotinoid seed treatments will generally provide acceptable control. The TIP tool should allow proactive decisions to be made relative to thrips managment.
How confident should I be using this TIP tool? My thoughts are exactly as those of my colleague at NC State who answered this question very well. Any forecast will have some uncertianty. However, this tool is based on many years of data from across the Southeast US Cotton Belt and has been validated several years since. We are very confident that this tool, when used as instructed, will accurately forecast thrips risk in cotton.
The TIP tool will not replace scouting and sampling for thrips and thrips injury in cotton. But it does provide information which will improve our thrips management programs.