Spawn Grass On Specific Texture In Landscape Material

Hello,

Im try to get grass to spawn on a specific texture. I am using a material which automatically updates the texture based on the height. This makes it difficult to do.

He is what i have so far:

Is there a way i can check to see if the texture painted is grass and then spawn the grass meshes?

Thanks Harry

Entire Landscape Material: Landscape Material posted by anonymous | blueprintUE | PasteBin For Unreal Engine 4