Created this procedural bush system while working at Lighthouse VFX. This system allow us to create a bush in any shape, orientation , wind simulation and so.

This system creating procedural tree using Houdini Lsystem , VOP & VEX:

-Calculating bush size and emitting same amouth of points. With this method , each bush emiits same number of points for your scene and bush looks more natural
-Creating wind dynamics for bushes with VOP. This way we dont need wire simulation or so and this method more faster more cheaper than wire dynamics.
-Creating 4 color and scale leaves.