Just a technicality- POC shafts are all heartwood, so what you're seeing is pitch, rather than sap. Sap is only in sapwood!
I agree with Bill- this is probably fresh stuff. Before the spotted owl controversy, POC shafts were harvested from snags and downed logs that were left behind after the live old-growth trees were cut. The dead logs may have been lying there for a hundred years. When old-growth cutting was restricted to "save" the owls, the POC producers were left with live timber from second-growth stands. It's different.