Crash and Missing tree segments upon generation

I made a brand new world which keeps crashing, I tried generating it again with the same seed and the problem is worse.

I assume (partly from the crash report) that it also relates to that world missing large sections of trees (see screenshot)

It seems as though which log and leaf blocks are missing varies each new generation attempt, but there are usually quite a few, and it's way too soon and persistent to be endermen