Vegetation has always been a neglected topic when it comes to tutorials. So I have decided to give the community exactly what they have been asking for. This method makes a tree with a reasonable number of faces. (mine came out to 7,128) This allows for having multiple trees without your scene becoming too heavy. Another great thing about this method, is that you can use it in the blender game engine. If you’re not using Blender, you should be able to use the same methods in whichever program you are using.
Check it out here (http://scotchtapeworm3d.wordpress.com/2010/10/06/tutorial-realistic-medium-poly-tree/)