>You don't need a single tree across the entire timespan you want to look at. Yeah, I was thinking more in terms of scarcity being an issue for samples that ex

>You don't need a single tree across the entire timespan you want to look at. Yeah, I was thinking more in terms of scarcity being an issue for samples that existed during particularly ancient periods in question. However, it seems the samples need not be living nor complete, and we've quite the extensive archive of dead wood dating further back than I could have imagined.