Chadeaux
I will venture a guess that if made by "Native American" artist the "head"?, is either looking at something of importance or standing guard over the burial mounds.
If made at a later date by someone of "masonic" knowledge then i would guess there could be a "lay-out" in the area using the same type "heads". (ex. if shown a dog's head on a tree, then look for additional dog's heads on other trees or rocks etc.) Plot on a grid or topo and go from there?
Good Luck
Oddrock