A lot of the tree meshes become big and blocky at the furthest LOD level. This causes them to look odd when they are far away in the distance.
This is a regression from 4.13.2
Result: Mesh becomes a big blocky object due to the wrong material being applied in LOD2
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-38472 in the post.