This year for the first time I grafted in what to me was bulk, about 60 apple trees. I had a 70 percent take rate which I thought was great specially because some of the grafts were less than ideal (substandard material, trying to see how far I could push it). Unfortunately on the group that took, nine decided to wither and die.
None of my apple trees suffer from anything like this, none of the failed rootstock that grew their own branches had any issues. There were some full sun days but they were properly watered at all times. Is this just a failure to take the graft or a disease thing?