it is said that the lifespan of a tree is influenced largely by the longevity(and disease-resistance) of its roots.
i can’t say if hidden springs nursery’s recommendation is accurate, but can’t disregard it either.
nigra mulberries reportedly easily attain >500 years’ productive life. And from what gathered online, alba’s generally last 150 yrs(though heard of some that lasted 400 yrs). Rubras reportedly start declining or only live as long(or if in nigra terms-- as short) as humans ~75 yrs.
nigras do come from seed, so the question would be that if many of the presumably seed-grown ancient trees that @chriso and @Carld posted here would have shorter lifespans if stems taken from them were to be grafted to rubra or alba.
another permutation is if it is true that senescence of roots is real such that a hypothetically air-layered nigra would be considered as old as the tree it came from and not revert to the youthful equivalence of a recently germinated nigra seed.
if we take budwood from a 250 yr old seed-grown nigra tree, then successfully graft it to a 1 year old rubra seedling, does this mean the scion will only have ~75 yrs left? Now, if we should plant the grafted specimen deep, in the hopes that the nigra will develop roots someday once the rubra starts declining, will it then equate to the nigra ‘resuming’ its projected lifespan of > 500 yrs?
as a kid(back when depeche mode and tears for fears were huge) have been planning to do it on determinate tomatoes by taking serial scions and serially grafting to determinate tomato seedlings and see if the determinate tomato scion will be artificially conferred immortality. I already know a cutting of determinate tomato will have the same-- if not shorter lifespan as the mother plant.
also curious if an indeterminate tomato will artificially increase the longevity of a determinate rootstock, or vice-versa. Sadly this kid’s procrastinating ways have indeterminate lifespans