Al...,
Al,
Look to your left, (
tap, tap on the screen).
Here's a classic pine knot, Al-beit a small one. The term's usually used to describe the resin-rich rock-hard branch collar of pine that is so dense it even has the the weight of stone. Along with old (bull)pine roots, it made up the fat- or light-wood that was tar kilned for naval stores, its resin then rendered for the turpentine, pitch, and rosin used for shipbuilding (naval stores). You can light one of these with a match, and these smokey torches illuminated many a Piney cabin.
Not only are they rock-hard, but they are incredibly decay resistant. Could it be that large pine knots were used as survey stakes, or even perhaps these knots were somehow identified on a standing stump?
S-M