Problem with how i've set up lighting in the scene or problem with my tree?

For some reason the lighting on a few of my trees are messing up. all of my trees has been made in speedtree, however with the most resent bigger trees im getting a lighting problem on the leaves, however the leaves are both made from the same textures and everything is completely the same setting wise in speedtree. was wondering if anyone knew if this was a problem with my lighting or post processing maybe? any help would be appreciated