I've seen this same issue in earlier one think I seen it going on in the current java development versions also.
If you notice there is a tree in the picture that the outer edges and branches are at a different height that the middle of the tree.
It looks like the tree was created before the land was lowered in that area. I've also seen area where it looks like someone just took a knife and cut the side off of a long strip of forest. This is on new maps.
Thank you for your report!
However, this issue has been closed as Cannot Reproduce.
We were unable to reproduce the problem you are describing in the latest version. If you are able to obtain a seed and location so we can reproduce the bug, please add it below.
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