Are they corn ear borers Maggie?

Around these parts, spraying with BT, combined with applying mineral oil to the top of the ear with an eye dropper are necessary to control corn borers. Successful organic corn is pretty labor intensive because it requires so much vigilance and spraying. I've not tried to grow corn since I moved to NC because I know I don't have the time to spray as often as needed, and certainly not enough time to treat each ear with mineral oil.

More here.

and here.

Not everyone agrees that organic corn is that hard.   See this.