Speaking of agriculture, I have seen studies that said a large portion of any deers diet consists of natural browse.
I think it depends on location. Here in Alabama I would agree. In place I have seen in Indiana and Kansas, the land is 80% crops and open pasture and about 20% woods if that. The only woods left are what they can plant on. These wooded bottoms become a travel and bedding areas for the deer. Some of the deer trails in these area look like cattle crossing because it is the only cover they have to move around in. I can't see these small area sustaining a large portion of there diet. I think in these type area they have to depend highly on the crops that are planted.