gijoey1980 somewhat hit on what I was going to write! The reason you that you may not be finding anything above or below the general line that you found the 4 prongs on, is probably due to: 1) It being the off year in their' cycle as not all Ginseng comes up every year and I have heard of and believe that some of the old sengers are correct, that some seng only comes up every third year. I have actually been on ridges and in hollows and found Ginseng there that was not there the two previous years I looked and I am not talking about flat tops or 2 prongs but 3 and 4 prongs. 2) Since this is either your' land or you have permission to hunt it, I doubt that it was planted by someone. It was more than likely brought in by seeds by deer, turkey and grouse and that is why you are seeing it along the game trails. I have hunted Ginseng in a lot of places from flat lands to small ridges and hills to steep ridges and even bluffs but have generally always found more Ginseng growing along game trails.
I bet that if you go back to that hollow next year, that you will be pleasantly surprised and find more Ginseng not only along the game trail but probably above and below it. Now the big question is, if deer, turkey and grouse are the propagaters of the Ginseng along the trail, did the seeds all come from this hollow. I would say no and that you need to follow that game trail both directions and you will probably find the source eventually. I have found Ginseng on game trails on some ridges and followed the game trail up across the top of the ridge and actually found Ginseng growing on the top of the ridge and then down the other side.
Good luck!
Frank
Frank