I think L System is also formatted for the Mac if I remember right. I don't know about plant designer. Both of those are freeware, but the drawback is, they make horrendously large files. Both however, allow you to seperate the plants into their seperate components for texturing. I don't recall the URLs at the moment, but if you enter L-System or Plant Designer into your search engine, it should find it, and they may be linked here somewhere on Renderosity in the links or resources sections

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