I am not sure of everything you have. But early in the season, they usually feed on left over red oak acorns, beach nuts, maple seeds, if there are any available. And just because the acorns have germinated doesn't mean that they don't eat them. I have killed hardwood mountain turkeys thats crops were full of germinated red oak acorns.
Food plots will help them, but I have expereince when they get so tall they aren't as productive for gobblers. Hens will nest in them, and they will also eat the seeds, and the insects that fill up the seedheads, but gobblers are reluctant to go into them and strut back and forth. Your flat hardwood ridgetops, benches, and flat bottoms will be likely places gobblers will hang out earlier in the season.
I don't have much luck in hardwood mountains though after the first two weeks of the season. They seem to migrate to areas of big cow pasture, 1 year old clear cuts, and whereever else hens can leave to find better nesting ground and brood habitat.
