Large spruce tree (2x2) can generate half or fully floating

Step to Reproduce
1. Use the seed in the original description with Caves & Cliffs experimental toggle on. (-1426640685)
2. Go to -840 120 600
3. Check some of the large spruce trees.

Observed Result
Some large spruce tree generates half or even fully floating.

Expected Result
All large spruce tree generates on podzol support on the ground.

Original Description
Summary
When encountering the 2x2 variant of spruce trees found in the new spruce mountains, they often generate almost "floating" because the base of the tree often does not connect properly with the slope it generates on. This problem is not apparent when the 2x2 variant of spruce tree generates on flat land (not on a slope). The many images attached which show examples of the problem use the world seed -1426640685. The problem is not apparent with the "normal", more commonly sized spruce trees.