The way it was explained to me by a retired USFWS biologist, now a consultant, You can plant corn and hunt it the same year as long as you treat it like a true farm crop. Don't go out there and just knock it down, then it becomes baiting. If, however, your combine is really old and leaks a lot of grain then oh well. You can also leave it standing as it were not worth harvesting and thats ok as well. The standing corn may not be as appealing to the ducks though.
You may also try planting water grass and flooding up. This can also be hunted the first year.
What part of "shall not be infringed" dont you understand?