I notice that a lot of birches are partially overgrown by algy, which would offset the pure whiteness of the bark. And would make the green branches look good again. Although in our 'rough birch' the smaller branches are a shiny sort of dark gray/green, not as bright as in your initial object. To get this algy, you can always put an extra (one color greenish) PF in the part shader.
---Dune
