This is another upright rock that was placed next to a tree. It had been there so long that the tree had grown over part of the rock.
Many of you may have seen this one before. This is one of the few ACTUAL metal clues I have ever found. This knife was placed inside a tree. The outlaw had bored a hole into the trunk of the tree and placed the knife inside. The tree grew closed around the knife. It took a chain saw to cut open the tree and retrieve the knife. In this case, the knife was pointing on a specific compass heading that when added to another compass heading in the map made a 90 degree "corner".
This is yet another upright rock used as a clue. Are you sensing a pattern here? This one was used as a "you are here" type marker just to mark a point along the trail on the map.