WEST MIDDLESEX, Pa. – Ron Hammond, the “go-to guy” on gray garden slugs in Ohio and Pennsylvania, gave his annual dose of slug control therapy at the Tri-State Conservation Tillage Conference Jan. 22.
If you no-till or minimum till, chances are you’ve had problems with slugs eating your young plants. They just love to overwinter on all that residue you leave, then the juveniles (leave it to the teenagers) chomp through your seedlings in late May and early June.
What can you do? It’s too late for this growing season, but next fall be sure to walk your fields and look for adult slugs. Fall sampling will let you know if you’re going to have a problem the following spring. And check all your fields, because the population will vary.
If it looks like a field has a problem in the fall, be sure to plant that field first, Hammond recommended.
Get in early. It helps if you can plant your crop early, said Hammond, a field crop entomologist for OSU Extension and the OARDC. The slugs will still be there, but your plants will outgrow them and can withstand some of the damage.
“It’s basic logic,” Hammond said. You want your crop planted, emerged and growing when the slugs are eggs, not when the slugs are the hungry teens.
Lend a helping hand. Do anything you can to get that crop growing quickly, Hammond added. Think row cleaners, strip tillage, starter fertilizer. It won’t affect the slugs, but it will help your plants grow and beat the slug life cycle.
Use an insecticide. What’s labeled for slugs? Deadline MPs, Metarex, Orcal Slug and Snail Bait, and Sluggo are all labeled for slug control in corn and soybeans. The first three contain metaldehyde as the active ingredient; Sluggo is an iron phosphate product. Products like Sluggo are approved for organic production, but are more expensive and Hammond said they’re not as effective at similar rates.
Metaldehyde baits are extremely safe materials, he added. “Pure caffeine is more toxic than metaldehyde.” And he’s never had them fail in any test he’s conducted.
Don’t be in a hurry to respray if you think the first treatment didn’t work, Hammond cautioned. Check where the slug damage is. If the new middle leaf on corn, or the newest trifoliate on soybeans, is intact, you don’t need to retreat.
Be sure to check your applicator and the recommended rate. Hammond said most treatment failure is due to improper application or not getting the recommended rate where it belongs (you sprayed on a windy day).
Tillage helps. If you no-till, you don’t want to hear it, but tillage does help fight slugs, Hammond said.