How to transplant 1 year apple tree damaged by black walnut.
Hello: last year I planted a frostbite apple. It is not doing well and I found out that it is too close to a black walnut. Should I wash the soil from the roots or try to keep as much as possible on roots
While it is possible the black walnut is causing issues with your apple, there are many other reasons a tree might struggle, especially when newly transplanted. Below I will give you a couple of links to a series of articles on transplanting established trees. But you will note that in the article it says that one reason NOT to transplant is because the plant is struggling. You might consider simply starting over with a new tree.
As for special considerations because of the black walnut, I'd not do anything unusual. If you transplant to a new location, the roots will soon grow into more hospitable soil. Furthermore, there is some evidence that the effects of juglone on other plants have been overstated. Read here:
Here are the links to the articles on moving trees and shrubs: