New roots for an (old) tree

Asked June 1, 2020, 5:58 PM EDT

I have a small (3 yrs) apple tree that I grafted in 2017. This spring I noticed that the trunk is malformed and bark is missing for the lowest 3 inches on one side. The tree is filled with leaves, but no longer supports itself - the roots have rotted. Based on advice from a nursery, I cut off the tree and pulled up what was left of the bottom couple inches. They told me the tree would not be viable. . . but This was one of my first successful grafts, and I'd love to save the tree. Is it possible to cut off anything discolored at the bottom and promote new roots? It still has about 12" of the rootstock.

Washington County Oregon

3 Responses

Probably not a good idea.

It is better to start over with some good hearty root stock. You could try to save some scion from your original graft to use and graft it to the new root stock.

Rootstocks

Select a tree from a nursery that matches the needs of your site. Most fruit varieties are grafted on size-controlling rootstocks, or rootstocks that are tolerant of wet soils or certain insect pests. It helps to know the characteristics of these rootstocks. Apples have the greatest number of rootstock options. In most cases, homeowners are encouraged to use semi-dwarf rootstocks like EM 7 or MM 111 because these trees do not need to be staked and will produce larger crops than the dwarfing rootstocks MM 9 or MM 26. The latter two rootstocks would be preferred if a homeowner has very limited space. Most trees sold in nurseries as semi-dwarfs are on EM 7.

Here are a few publications to check out:

https://extension.oregonstate.edu/news/apple-trees-benefit-proper-pruning-spring-summer

https://extension.oregonstate.edu/sites/default/files/documents/1/2011-segraftingfruittreescompatibilitymode.pdf

Hope this helps!

Thank you, Chris. Especially for such a quick response. I've always been told to do grafts when the trees are dormant. But here, I have a cut off tree at the beginning of summer. It was becoming such a lovely tree! I have some extra root stock - is it worth a try now? Suggestions welcome.
Arlin R

You could try to graft now, although there is a low percentage of success.

You could save some scion (cuttings from your favorite tree), keeping them in plastic in a refrigerator until the dormant season as a safety net.

Good luck, and thanks for contacting Ask an Expert.