In Illinois, I've had deer feed heavily in picked soybeans picking up the "dregs," but it has often been later in the season as colder weather prevails. About 5 years ago, all the wooded areas I hunt were surrounded by beans. Up through the rut, it seemed like the deer had no interest being in the fields at all.
That year, though, from December 10th on, it appeared that the soybean stubble became the favored place to be. Almost every afternoon, they were there from about 45 minutes before sunset until darkness fell.
I thought there was a chance that their nutritional needs change somewhat as cold weather comes on. If they need a higher level of protein, the soybeans would be THE place to be!
Make sure you check on the fields later. When the wind is just right, your trail COULD be a gold mine!