IPM, Resistance, and Disposal After the Season
A greenhouse grower has a recurring thrips problem on ornamental crops. For three seasons the grower has used the same pyrethroid product every 7 days at the highest labeled rate, plus a soil drench of the same active ingredient. The grower reports that control has declined and wants to increase the rate beyond the label and shorten the interval to every 3 days. The grower also has about 15 gallons of unused pesticide concentrate and several partially filled containers left from last season, stored in an unheated shed. The applicator is asked to advise on the thrips program and on disposing of the leftover product before winter.
1. Using IPM principles, how should the applicator address the declining thrips control and the grower's proposal to exceed the label?
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The applicator should explain that exceeding the label rate or shortening the interval below the label is illegal and not a legitimate resistance-management strategy. The pattern of repeated use of one mode of action, including a soil drench of the same active ingredient, is a classic resistance-selection problem. An IPM approach would include confirming the pest identity and monitoring with sticky cards or counts, rotating to products with different modes of action, using biological controls where compatible, improving cultural controls such as sanitation, weed removal, and environmental management, and applying only when thresholds justify treatment. The applicator should review the labels for allowed rates and intervals and design a rotation program consistent with label directions and resistance-management guidance.
2. What should the applicator advise about the leftover pesticide and containers stored in the unheated shed?
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The applicator should advise the grower to inventory the products, keep them in a secure, properly labeled location, and follow label storage directions, including protection from freezing where required. Unusable or unwanted pesticides should be handled through Connecticut's pesticide disposal or collection programs rather than dumped, burned, or placed in the trash. The grower should contact DEEP or the state pesticide program for disposal options and any collection events. Containers should be managed according to label and state rules, including triple rinsing where applicable and proper disposal. The applicator should also help the grower avoid future overstock by purchasing only what is needed and tracking inventory.