I saw a Urho3D video on youtube some months ago demonstrating replicated grass in the scene. I don't know how many grass nodes were placed in the scene, but I clearly remember the low frame rate at around 20 - 35 fps.
I wanted to test this and test to see if some optimization can be made for sometime now and got a chance to today.
Rendering 10k grass nodes created individually using staticModel, the frame rate sat around 67 fps.
Replication w/ normals overriden:
Added wind animation:
Edit: added another screenshot