What is Integrated Pest Management (I.P.M.) for Slugs?

Chemical baiting has been a powerful tool for controlling slugs in field crops, however there are many factors that affect a bait’s efficacy, and other negative effects for using excessive baits as the only tool for control. In addition there are now multiple slug species found in the Pacific Northwest, with different feeding strategies and environmental needs. In summary, there is no ‘single solution’ for controlling slug pests, which thrive in changing environments. Exciting progress is being made by the hiring of a slug specialist at Oregon State University, hence this will increase our knowledge of slug ecology and behavior, slug community and composition, and the use of alternative control methods. The future challenge will be translating knowledge into practical solutions for the growers.

An effective Integrated Pest Management (IPM) program minimizes slugs by utilizing multiple practices, and does not encourage a single pest control approach. A selection of tools should focus on least possible hazards to humans, field property, and the surrounding environment. A good IPM program also exploits comprehensive information regarding a slug’s life cycle behavior, and the needs of slugs——and their relationships with the environment and weather conditions, inside and adjacent to the field. Practical and cost-effective tools that can be incorporated into one’s farming system are key to grower adoption.

Monitoring and Establishing Action Thresholds

Solutions should be based on the correct identification of the slug species found in your field. Before taking control action with baits or other approaches, did you closely monitor for slug levels? IPM users should set an action threshold—a point at which slug population numbers will become an economic threat and crop losses will occur, if an action is not taken. Finding a single slug does not mean control is needed—a predetermined threshold is critical to guiding slug control decisions, but thresholds are not known in the PNW. We encourage users of this site to send feedback on the number of slugs that determine your need to treat a field (contact Rory McDonnell).