Guys, you need to remember that most old billboard stuff will not work very well in TS12, problems with alphas and lighting, reverse side of planes are badly effected by this, that's why some of us produced trees using different exporter values.
I have literally over 12 months ago now tested virtually every available Tree that was available on the DS regarding appearance in TS12 when actually running the sim, not setting up for Screenshot of the month, which resulted in me making my own..........
Cascade you might want to look at my efforts under CL Tree and CL Bush which are made using 4 twisted planes, give them a fuller and closer to 3d look and will unless you are right on top of them, stand scrutiny from any direction. Easily done, lighting issues solved by splitting ambient from diffuse and adjusting separately to nullify the lighting, one or two others are doing similar.
I did this as I needed Trees and bushes on the DLS for my route (Promised it would all be on the DLS) that were not nervously twitching, gigantically oversized or looked like green blobs, had variations in colour without peculiar lighting effects or a visible haze round the tree or are transparent and actually work.
I'm no tree expert, I have no idea what trees my efforts represent however if I can do it I'm sure there are those who could do much better ;o)