Just as a point of reference, this was my liner today after a full season, somewhere about 1.5 cords. It was mostly Oak, CSS by Summer2019. I was pleased, although the screen on my cap did have more shiny black creosote than normal, it wasn't much and I attribute that to splits from the very bottom of one stack that wasn't very high off the ground. It should have been immediately apparent, but somehow it took me a few days to figure out what was wrong. That only goes to show that two years is a bare minimum for Oak. Less than a quart of dry brown creosote/ash , barely a speckle of anything shiny.
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