Reduced risk insecticide: Entrust

Christell Guedot, UW-Madison, Department of Entomology

         Entrust is registered for use in Wisconsin* on many crops, including cranberry. It is marketed by Dow AgroSciencesÒ under the formulations 80WP (80% active ingredient as a Wettable Powder) and 2SC (2 lb. of active ingredient per gallon as a Soluble Concentrate). Entrust is a Naturalyte insect control product that is OMRI approved and contains the active ingredient Spinosad. Spinosad is biologically derived from the fermentation of Saccharopolyspora spinosa, naturally occurring soil bacteria. Entrust is in the class of the Spinosyns (IRAC code 5). Its mode of action is primarily on the nicotinic acetylcholine receptors, causing excitation of the insect nervous system which leads to muscle contractions, paralysis, and eventually death. Entrust is most effective through ingestion of treated plants but also has effective contact activity.

         In cranberry, Entrust is registered for insect suppression (not control) of armyworms, fireworms, leafrollers, looper, sparganothis fruitworm, and thrips, as well as currant fruitfly, European grapevine moth, and light brown apple moth.

         The timing of application should coincide with egg hatch or the appearance of small instar larvae of the pest to be controlled for optimal results.  Thus scouting of life stages and monitoring of degree days will improve the efficacy of Entrust. In our previous trials, Entrust has performed well particularly in organic production and this article is primarily intended for organic growers. In conventional production, Entrust does not perform as well as commonly used conventional insecticides and could be considered in a rotation manner to delay resistance to these more commonly used insecticides. From Jack’s experience, a tight application schedule of the highest rate combined with several applications will provide the best control on fruitworms and loopers.

         Entrust may be applied by ground equipment, chemigations, and by air (see label for specific application regulations). Dilute sprays should be sprayed to the point of runoff.

         Entrust is toxic to bees exposed to treatments for 3 hrs. following treatment. As a precaution, avoid applying any pesticide during bloom when bees are flying.

         Entrust is toxic to aquatic invertebrates and must not be applied directly to water.

*Entrust is labeled for use in cranberry in Oregon as well