Not fresh roots, but in a lecture I was listening to about Rhizophagy, James White talks about Iroquois (and likely all native americans) making “corn medicine” by making a brew of the previous years corn crop roots and inoculating the seed for planting with it, alongside ceremony and other additives and herbs unknown. Haven’t found any specific references in my own cultural heritage (Cherokee) but the concept has been around a LONG time. I’ve had some fun doing similar with the roots of Arizona Cottontop in the wild and applying it to seed to get the biology the plant needs present on the seed coat.