I have seen corn combined in the snow, but it is unlikely that it will be much of an issue. I try to pick up the antlers on the fields early in spring when it is easy to find them. Some times I miss a few and they end up in the equipment. Would be missing quite a few if I had to wait until May when on some years there is already substantial new growth.
The problem with the shed season is it doesn't address the real problem. Picking up a shed does not stress wildlife, people on the winter range can, Sheds may be the reason of the people are there, but a shed hunter does no more damage than a photographer, birdwatcher, lion hunter and many others. If you are serious about protecting wildlife when they are vulnerable, you need close the winter range to all activity's.