Yeah, fresh manure can be pretty hot/high in free ammonia. If you can mix it in yearly piles with leaf litter and shredded garden clippings, and then use last years pile it's pretty safe. But, you don't know how rich it is without experimenting. Mixing some aged stuff into planting areas like 6 weeks ahead of planting and then side dressing a couple times over the grow season is what I've heard others do, but I haven't tried raw inputs like that myself. Not sure how much and all that.
Corn does need a fair bit of nitrogen to grow well, though. That much I'm sure about.