Hm, I don't really know of the forest pack you're talking about, but I can tell you one thing. The textures look a tad off, because wouldn't the planes on the tree at least have some alpha mapping applied to the leaf texture? So that may be a problem. Also make sure if they're static, because the trees may be set too lightweight for the purpose they serve.
I can't really do much else for you right now, and would you mind posting one of the .fpe's for the trees/plants?
![](http://img404.imageshack.us/img404/4853/sigfy9.jpg)
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