Question: how can you tell the difference between Southern 60 chromosome American Persimmon and the Northern 90 chromosome American Persimmon. I’m curious for where the ranges overlap (like maybe Virginia or Maryland).
I got some rootstock from up north (Cold Stream Farms) and it looks slightly different than what i got from Maryland State Nursery. but maybe its just the way they grow them (Cold Stream a bit more spindly, Maryland a bit more straight whips… although Maryland has a maybe slightly more green color bark close the ground-level, Cold Stream more dark purple color bark).
Question#2: would the Southern one be bad to graft onto in a 7a/7b area (Philadephia) its pretty humid here like the South (well prob not as much as the deep south :), but i guess winters here are colder). Wondering how far zone-wise that rootstock can push in case I got some Southern ones.
EDIT: found this to maybe answer 1st question. 2nd question… not sure how far north be4 the cold-hardiness of the 90chromosome is definitely needed. Maybe I’ll ask Cliff one of these days.
There exist two races of American persimmon, a ninety-chromosome, “northern” race and a sixty-chromosome, “southern” race. The “northern” race is native to the upper Midwest of the U.S. and is the earlier ripening and more cold-hardy of the two races. Also, the pubescent leaves and larger fruit (which occasionally are bluish) of the “northern” race contrast with the smooth leaves and smaller fruit of the “southern” race.
Jerry Lehman is one of the national authorities on persimmons. He was asked if there is an easy way to tell the difference between 60 and 90 chromosome persimmons and this was his response:
Outside of planting seeds and doing a count of the newely emerged root tip with a microscope there may not be a sure way. However, I’ve looked at many persimmon trees in may parts of the US. I’m not sure there is a dividing line. I believe they are very mixed in the south midwest. My observation is there are two general types and I assume the chromosome numbers is the difference. The type which I believe is the 60 has smaller generally more glossy leaves, smaller fruit, twigs smaller diamater and the smaller fruits that require a considerable longer period before ripening. If I’m correct on the longer ripening period that is why they don’t range naturally in the northern areas, the seeds don’t mature before the growing season ends.