Answer: Ants in the vegetable garden are annoying, to say the least! Since you're going to eat your veggies, you'll want to use a botanical insecticide. There are several that are labeled for ants. They include Bonide Rotenone and Pyrethrum, Safer Crawling insect Killer (which is diatomaceous earth plus baits) and Safer yard and garden which is insecticidal soaps plus pyrethrin. Follow label directions for best results.
As for thinning corn, give each stalk 10-12" of growing space all around.
Good luck with your garden!
Q&A Library Searching Tips