Apple tree damage. - Ask Extension
My dwarf apple tree about 5 years old . I came to work in the morning this week and found it broken at the base of the trunk. It had been staked up...
Knowledgebase
Apple tree damage. #873137
Asked June 14, 2024, 3:16 PM EDT
My dwarf apple tree about 5 years old . I came to work in the morning this week and found it broken at the base of the trunk. It had been staked up as well. Don't know what may have caused it. Any suspicions from the 2 pictures. It is called Bakers Delight from Gurney's.
Bay County Michigan
Expert Response
This looks like the graft union (junction between the top (scion = variety, in this case Bakers Delight) and the rootstock) was weak.
Sometimes this is due to a virus causing incompatibility. The virus is carried along with either the scion or the rootstock. But we don't know if a virus is involved without expensive testing.
https://www.canr.msu.edu/ipm/diseases/apple_union_necrosis_and_decline
Some rootstocks are prone to brittle graft union--example Geneva 41 rootstock. You may not know the rootstock used for your tree.
https://www.goodfruit.com/good-to-know-signs-of-brittle-graft-unions/
All these are speculations without doing testing.
Sometimes this is due to a virus causing incompatibility. The virus is carried along with either the scion or the rootstock. But we don't know if a virus is involved without expensive testing.
https://www.canr.msu.edu/ipm/diseases/apple_union_necrosis_and_decline
Some rootstocks are prone to brittle graft union--example Geneva 41 rootstock. You may not know the rootstock used for your tree.
https://www.goodfruit.com/good-to-know-signs-of-brittle-graft-unions/
All these are speculations without doing testing.
