Red oak species(southern, nothern, scarlett, pin, etc) have higher tannin levels(makes them bitter), while white oaks species(chestnut, rock, basket, willow, overcup, post, turkey, etc) have lower levels of tannin and some are actually sweet enough you can eat them right out of hand if you pull the meat out of the shell. Deer will eat both species, but certainly prefer white oaks species.
There is a large corn field about .75 of a mile from our land in PA. Even though the hillside our land is on is covered in white oak and red oak acorns, the doe I shot up there back in early October was packed with corn. She had obviously spent the night gorging on corn and was coming up the mountain to chew her cud and take cover for the day and maybe grab an acorn or too to eat.
An interesting example of deer food preference are brassics(turnips, kale, radishes, etc). I've planted them in some areas where the deer destroy them even before first frost. Then in other areas, even where deer densities are low, the deer wont even touch them after several frosts. It's almost like they have to learn to eat some new foods?
