The Potential of Chemical and Biological Management Options for Controlling Jumping Worms (Amynthas spp.) in Container Nursery Production

Jumping worm species belonging to the genus Amynthas (Kinberg) threaten biodiversity and soil health significantly across temperate ecosystems. One inadvertent method of invasive jumping worm spread is through container-grown nursery stock. In nursery production, jumping worms modify substrate characteristics such as water holding capacity and nutrient availability by consuming and redepositing organic matter, resulting in negative effects to plant quality and appearance. There are currently no products listed for controlling jumping worms in the United States, leading to challenges in managing their spread. With increasing regulation on the transport of jumping worms by state agencies, plant producers may face unrealistic or labor-intensive management options. We hypothesized that control methods not yet listed for jumping worms in the United States have the potential to suppress jumping worm populations effectively in container-grown crops. Therefore, we studied chemical and biological controls touted as potential options for controlling jumping worms in nursery containers by measuring their effects on jumping worm mortality. In addition to an untreated control, we evaluated BotaniGard Ⓡ 22WP, T-Bird Ⓡ 4.5L (thiophanate-methyl fungicide), Root Cleaner Ⓡ (sodium lauryl sulfate and soybean oil), Cedarcide Ⓡ (cedarwood oil), Conserve Ⓡ SC (spinosad), Castaway Ⓡ 3-0-1 Tea Seed Meal Fertilizer, Slug Magic TM (iron phosphate), and Sevin Ⓡ (zeta-cypermethrin). The results of our work suggest differential efficacy among treatments and highlight viable options with the potential for application in horticultural production. Specifically, T-Bird Ⓡ 4.5L (thiophanate-methyl fungicide) and Sevin Ⓡ (zeta-cypermethrin) demonstrated at least 80% mortality in two trials, whereas all remaining products yielded no effect or less than 12% mortality. Identifying effective control methods benefits the scientific community and the horticultural industry by providing a foundation for future research activities centered on jumping worm management and by supporting the goal of limiting their spread through horticultural products.