Since vurt kindly agreed to let us use his assets, this is what i've already converted.
https://mega.co.nz/#!1MkQzRrb!cvI-EyAgaxHck58rjbfEWjRfbQkpaXWy6wmzisjByzI
The trees have no collision meshes, no ambient occlusion (that's why the original look a bit better)no animations of course and there are probably a lot of useless textures in this pack because I've copy/pasted everything from his mods, but it already looks really great ingame.
This is just a ressource, it won't do anything if you drop it in your install^^ (I've made an esp but I wont release it here, it would require too many different assets)

How many trees are there? I
How many trees are there? I think they make a pretty good fit for the Bitter Coast area.