Slug control in strawberry
This wet spring is making conditions perfect for slug activity.
The recent wet weather is cause for concern for strawberry growers who have wet fields and ripening fruit. Slugs do well in damp, cool weather, and we have had plenty of that this year. As strawberries ripen, slugs can damage berries by feeding on the base of the berries near the soil making them unmarketable.
In our research a few years ago at MSU, we compared the standard Deadline Bullets slug bait product with Sluggo that contains iron phosphate as the active ingredient. One of the potential benefits of Sluggo is that the bait is light brown, making it less visible to pickers, and it is expected to have less side-effects on other soil dwelling organisms because of the different active ingredients. It is also biodegradable and safe to animals. These products are formulated in a way that they can be spread the same way as a granular fertilizer.
We compared the two products at a farm in Sutton’s Bay, Mich., in a replicated field trial. Deadline Bullets at 25 pounds per acre provided excellent control of slugs over the month-long period between application and harvest, and reduced damage to harvested fruit by 95 percent, compared to the untreated areas.
Sluggo at 40 pounds per acre did not significantly reduce slug populations, but it did provide significant protection of berries from slug damage – 79 percent control – that was not significantly different from Deadline Bullets. It seems that the Sluggo has a less rapid toxic effect, but it does stop the slugs from feeding which eventually leads to their death.
Dr. Isaacs’s work is funded in part by MSU’s AgBioResearch.