Jones wrote:

I want to transplant some, but I keep finding that I cannot dig them up
deep enough to get all of the tap root, especially among the seedlings
that are last year's stock. These "trees" are only maybe 12" tall and
1/8" or less thick, but their tap roots are often more than 12" long
and 1/4" thick.

Yes, other highland trees do the same, that is, they first grow a
strong root that is disproportionate to the aerial parts. Walnuts,
oaks, hickory, chestnuts all do that. Even in my sandy, soft soil I can
not pull out hickory seedlings.


I've always heard that if you break the tap root of a young tree, that
it will either die or fail to thrive, but I wondered whether that's
true or just an old wive's tale.


The common method to deal with these trees is to seed a soft bed, and
then pull out the entire plant, or "whip", for transplanting. You could
consider doing that, and next fall you should have plenty of viable
whips for transplanting. If you want to try something this year, most
seedlings whose taproot has been damaged do fail to thrive, however,
not all. Some recover. You can transplant 6 or more to the intended
spot this fall, after the seedlings have lost their leaves. Next year
water them, then pick the strongest looking seedling and eliminate the
other ones.