Bagworms should begin hatching in the next 2-6 weeks throughout NJ, starting in the southern regions. Now is an optimal time to get this pest on your radar and prepare materials or approaches to attack first/second instar caterpillars. The control window for this pest is typically between 600-900 GDD50 (growing degree-days) and treatments should be in use prior to their mobile, airborne, “ballooning” phase. Check that the eggs have hatched prior to application of pesticides – as most compounds will not be effective at all if the first instar caterpillars are not present. Lethal pesticide doses are important, as sub-lethal doses can trigger early pupation, making the pest all but invincible to chemical or biological treatments.
Bagworm management – mechanical: If eggs have not hatched: hand-remove sacs/bags. Typically female/egg filled sacs are higher in the canopy so keep that in mind while scouting.
Treatment options for Lepidoptera (caterpillars) to have at the ready – containing: B.t. (Bacillus thuringiensis)(Dipel), spinosad (Entrust SC), bifenthrin (Talstar, UP-Star), cyfluthrin (Decathlon 20WP), carbaryl (Sevin SL), chlorantraniliprole (Acelepryn), cyclaniliprole (Sarisa), cyclaniliprole + flonicamid (Pradia), Lambda-cyhalothrin (Scimitar GC), cyantraniliprole (Mainspring), Indoxacarb(Provaunt)
IT IS CRITICAL TO ROTATE AS MUCH AS POSSIBLE BETWEEN IRAC GROUPS DUE TO THE NUMBER OF POTENTIAL APPLICATIONS
DISCLAIMER: The label is the law, always refer to it for allowable host crops, use-restrictions, application rates, reapplication intervals, re-entry intervals (REI), and mix compatibility information. Production and pesticide information on this site are for private/commercial pesticide applicators and landscape professionals only, and are NOT for home gardener use. Provided materials represent examples and do not cover all possible control scenarios. Trade-names listed do not imply endorsement and are used as examples only. Please contact your local agent or chemical sales representative for more information or to discuss additional pest management options.
More information on Bagworms:
Steve Rettke’s 2020 PPA Post – Bagworm caterpillars have hatched throughout most of NJ
Bagworms on Ornamental Landscape Plants
Photo Credits: Rich Buckley (Plant Diagnostics Laboratory) https://njaes.rutgers.edu/plant-diagnostic-lab/