Verified answer

this happens in sweet corn sometimes. Don't worry you can just cut off the suckers and it will be OK. If you don't cut off the suckers you will have smaller ears or no ears.

Are you sure it is coming from a single seed? It could be that you planted the seeds too closely. Otherwise, I'd say you may have a phosporous problem. Sometimes when there is too much phosphorous in the ground I believe that can happen to corn. It might be a good idea to have your soil tested to figure out what the problem is. Your local extension office should be able to test your soil.

Do you put a lot of manure on your garden. Manure can give a bunch of extra phosphorous.

It must be a genetic mutation. A mutation is a random alteration of genetic code from the normal. You could get rid of the entire plant.

i do not know what causes this, but thin to a single stalk,and let us know what happens.