I know corn seems to be the best but from my observations right now they seem to be hitting the buds from young trees right now in my area. I see no sign in the only corn field around my hunting area. But ive seen them browsing the woody areas and also digging for acorns in the snow. I thought for sure they would be hitting the corn with all the snow we recieved here in South eastern part of Wisconsin.
Even on my way home yesterday morning in IL I seen a small 8 PT browsing along the treeline.