I have run across threshing floor planks that appear to have been split from large pine logs and trimmed on the edges with an adze or axe. The one in particular was from the centre of the log and ended up about 24" wide and about 6" thick trimmed to 4" where its bearing point over a sleeper came. Has anyone historical knowledge about the exact proceedure used for splitting large logs into planks. I would appreciate any input in this regard