Standing stones

Today I went for a walk on the forestry track around Achnabreck, famous for it's cup and ring marked stones. The cups and rings are kind of concentric circles carved on the rocks many years ago. I have never heard an explanation as to why these were carved although many theories have been put forward.

Beside the track very near to the cup and rings I found these stones. They have been embedded into the tree stumps that were cut to make the path. Why has this been done, just because......Maybe it's the same for the cup and rings