In this two part tutorial you will learn how to set up a large scale forest in Blender, that is memory friendly and can be rendered using GPU in most cases. In the first part you will learn how to generate and render a 3d tree and use the rendered image as texture for an alpha mapped tree. Also, you will learn how to add several effects to this alpha tree, so that it is interacting with the light. In the second part you will learn how to fake a better ground shadow for the tree and how to set up a particle system to create the forest.
Resources mentioned in this video:
Here is how it works:


For achieving this effect, we will use a 3d tree as foundation, render an image with a transparent background from it and generate two normal maps, which will create the 3d look.
After setting up the tree, it’s pretty easy to set up a particle system to quickly generate a large scale forest. Below you can see two examples, the first one will be created in this tutorial. For in-depth information watch the video tutorial and download the project files (scroll up).