Spring is here and so are leafrollers and leafminers. DATCP reported for the first week of May average counts of redbanded leafroller (RBLR; Figure 1) of 44 moths per trap and counts as high as 729 spotted tentiform leafminer (STLM) moths per trap. For more information on these and other spring caterpillars, please refer to this previous article in this issue.

Pheromone-baited traps are available to purchase for monitoring adult populations and should be used in orchards with a history of RBLR or STLM damage. While the numbers may be quite high in some orchards, they will keep increasing until bloom and petal fall and it is advised to wait until petal fall to apply chemical controls. At petal fall, these caterpillars can often be controlled together using a single chemical spray. Insecticides include but are not limited to: spinosyns (e.g., Delegate and Entrust), diamides (e.g., Altacor, Exirel), growth regulators (e.g., Rimon), neonicotinoids (e.g., Assail, Actara), carbamates (e.g., Lannate), and organophosphates (e.g., Imidan).

Other chemistries and products are available, and we do not recommend certain tradenames above others. Additionally, you should always fully read the label before spraying any pesticide. If populations are high, it may be necessary to apply another spray later in the season and monitoring for adult moths and damage will help you decide whether you should spray again.

Happy growing season!

This article was posted in Apples, Insects and tagged insect control, insects, WFN.