RE: Field Corn or Soybeans??
The deer chew on the tender green soybean leaves this time of year. Later on they go after the beans for all the oil (fat). In the winter they paw up what's left.
Early season the deer sometimes bed in the corn fields, but there isn't much feeding going on until the corn starts to mature a little. By mid October I'd say they would definitely be helping themselves with the mature corn. From October until it greens up again in the spring is when they will feed on corn.