Since 2022, snails have been causing injuries to commercial fields of corn and soybeans in Kentucky. In 2022 a commercial soybean was severely affected, and in 2023 a cornfield was affected by a distinct species. In 2024, we found that at least three additional snail species were causing moderate damage to corn and soybeans. The occurrences of three native snails as pests of field crops have not been reported anywhere else in the USA. Injuries of native snails in field crops (corn and soybeans) have been uncommon compared with slugs, but there are recent incidents in Brazil and some states on the Gulf Coast that had the same invasive species that caused injuries in Argentina. Even though the injuries caused by slugs and snails are very similar (defoliation, feeding on apical terminals, cotyledons, and reduction of plant densities), there are potential advantages of snails over slugs. Slugs have a naked body, but snails have a shell on their back that provides shelter and protection that makes them less vulnerable to dehydration. The strategies of snails to resist dehydration include the presence of a thick fold of skin in the mantle to prevent water loss and periods of aestivation in response to seasonal changes; during aestivation, they produce heat shock proteins to resist dehydration. The behavior, biology, damages, potential as emergent pests, and recent move of these five snail species from their native niches to field crops may be important for KY and other states that grow soybeans.

Soybean farmers, consultants, county extension agents, and agricultural professionals started to notice the presence of mollusks as key pest of soybeans and damages that they can cause. These pests do not have remediation measures other than replanting of seeds. However, in 2024 we noticed the adoption on the monitoring of mollusks and use of molluscicide baits.