After painting on trees using the foliage editor, I often find that the trees are missing once in game.
However, they’re still there from a collision standpoint.
I thought I had it pinned down to any trees I selected and tried to move or adjust after painting them in but have since discovered it’s random.
In Editor:
In Game:
This happens with a variety of tree and or rock meshes.
If I go onto the ground and walk to where the tree should be I run into it even though it’s not visible.