This pond site has been in field crops since the 1950's at least based on historic areal pics. I dug up one old clay field tile run when I built it. The presence of pretty large diameter shoots, one plant in very deep water, baffles me. I know that cattail seeds can last over 50 years in the soil, but these phragmites look like they are coming from some larger rhizomes and have not found any info on them being able to lay dormant for that long. I suspect the site was quite wet before it was tiled, but was farmed in recent times.
