If wireworms found your field, maybe because you've had a lot of residue or maybe just because you're unlucky, the worst part is having to sit back and watch them attack your crops. There are no rescue treatments for wireworms, entomologists say.
But what you can do is hope for warmer weather. As the soil heats up the wireworms slither back down deeper in the soil and stop feeding on plants and roots.
There is more good news if you have wireworms as a primary pest. They likely are only working on the field in spots. What you will have to do is decide whether it's worth replanting an area because they thinned the stand so severely. There are soil insecticides that can control wireworm, and seed-coated insecticides should work on them as well.
With the good comes the bad: even if you don't apply any more manure, and even if you went to clean tillage, they could still show up in the same spots for from two to seven years. In theory, if you're in rotation, you could battle them for three more rotations of the crop if you had corn in the field this year.
There are also other pests out there to find, including slugs, which should also tail off as conditions warm up and dry out, and black cutworms. Depending upon when you planted your corn, this damage should also tail off soon. However, you ought to determine if they are out there now.
It's difficult to know why you have a stand problem if you don't find the poor stand until July or even late June. It's much easier to piece together what might have happened if you scout early and often. You will diagnose these problems and whether you can do anything or not, you'll be more prepared for next season.