Trunk extrusion UVs are messed up at the bottom of trunk

As title says, it seems to be some bug on extrusion UVs. If doing extrusion to about half of the trunk - everything seems fine, though near the bottom, it gets over-stretched resulting in wrongly mapped texture. https://imgur.com/a/hJqKVkI

As you can see in image, the bug appears only on the last 3 segments of extrusion. Any idea why this is happening?

Exact same bug is happening for branches extrusion