I’m getting quite a few calls about slugs taking out soybean plantings not once but sometimes twice in the same field. It has been an ideal spring for slugs with all of this wet cool weather. And last fall was wet too, which helped all those slugs lay eggs and survive in these problem fields.
Unfortunately there is not a lot that can be done (affordably anyway) as a rescue treatment. Only 1 in 4 growers who try the UAN 28% solution, sprayed 3 nights in a row, find it to work. Especially in a season when it continues to rain or experience heavy dews in the early mornings that can wash off the salt on the slugs. And Sluggo bait is too expensive to apply on field crops, unless used in very small problem areas and must be applied around May 24 to knock the population down when they first start up.
The only effective and affordable method of control is tillage. Removing the crop residue will get rid of the habitat that the slugs are hiding out in, being protected from the sun and heat. Till these problem fields in the fall since the slugs that are present in the fall are the same ones that will be a problem again next spring in that same field. Go back into these fall tilled fields in the spring and place shingles or small blocks of wood down on the soil surface. Check under the boards in the early mornings to see if slugs are hanging out. If slugs are easily found, then more tillage may be needed and potentially the use of the Sluggo bait in the problem areas of the field.
The good news is that once the weather does turn a bit more dry and warm, the crop should be able to grow faster than the slugs can feed and the problem will be behind you shortly. At least until next spring
Have a fantastic Canada Day Everyone!