fwiw. The leaves were made by parenting tris to an emmiter (instead of dupliverting to branches). Maybe someone will find the method useful. blend included.
Working with the technique I’ve since changed the method from the crossed card to a single quad ‘Plane’ card. Point the flat side to the camera or light and add a material. I’ve also changed the basic material from Voronoi to Musgrave with Multifractal Voronoi F1 as it makes the leave a little pointed. [/edit]