If its exceptionally rocky, and soils are "thin", its really not unusual to have highly acid soils. I had mine tested. Once the recommendations came in, and I saw what sort of insane amounts of lime I would have needed, I simply abandoned that site and looked elsewhere. The acidity explained why all previous efforts at food plots were a failure.
For what its worth, I moved to another site, maybe 90 yards away. Not as pretty, not as "this would be awesome for deer" looking. However, soils were almost neutral. Instead of the top of a rocky knoll, this new plot was predominantly clays and silts and much lower. And instead of failures, I had bumper crops of wonderful brassicas and turnips...
It sounds to me like you intended site is a total looser, from a food plot perspective. No soils, rocky, treed, no sunlight. I know a bag of seed is only $40, but I suspect its wasted effort. Find somewhere else where plants can actually grow. The deer will find it...
If you do find decent soils, an afternoon with a chainsaw can really open it up...