Skinning meshes to particles is a three step process.
1) Create your particles from the mesh (in your case, birth skeleton from grass mesh)
2) Duplicate the mesh
3) Put a tyParticleSkin modifier on the duplicate and select the particles you created as the source.
The reason you need a duplicate is because otherwise you get a circular dependency error (particles depend on mesh which depends on particles = infinite loop)
There are example files showing how to use the tyParticleSkin modifier that you can explore.
1) Create your particles from the mesh (in your case, birth skeleton from grass mesh)
2) Duplicate the mesh
3) Put a tyParticleSkin modifier on the duplicate and select the particles you created as the source.
The reason you need a duplicate is because otherwise you get a circular dependency error (particles depend on mesh which depends on particles = infinite loop)
There are example files showing how to use the tyParticleSkin modifier that you can explore.