Hey ya'll after some daunting and extensive web browsing I went through and made tree presets in Bryce and some lattice boulders for Daz3D which you can get on Daz 3D's site if anyone is interested, no need to find trees anymore I made em all for ya:-D (well the most known ones 62 in all) And there will be more to come soon:-) The rocks series, BTW you can combine them and make super structures out of them, they blend together when you stack em on top of one another, plus they have custom made materials you can save and re-use.! Not free but at a good price.
http://www.daz3d.com/i.x/shop/catmain/-/?cat=106

Do atleast one thing a day that scares the hell outta ya!!