Yes, it is legal to cut the corn and remove it from the field or use it for camoflauge on the blind.
However, in the process of removing it, it would be baiting to pull off the ears of corn and leave them in the field. If you use it for camoflauge, it would also be illegal to peel back the husks and expose the "yellow" corn.
Both of those answers cover the baiting part of it. There is also a WMA rule that deals with removing any plant life from a WMA. You should check with the Area Manager before taking anything out to make sure you aren't running into an issue there.