Collision problem with procedural foliage

- YouTube here is the video of the problem that i am experiencing.
I populated my world with trees using Procedural Foliage Spawner. I’ve put single capsule collision
on the trunk of tree. but vehicle collision works like there are collisions on foliage too.
I’ve checked vehicle collision, collision settings on PFS, Foliage types, capsule on the tree is correctly sized.
anyone know what cause this? and how to solve the problem?