Particles to spawn from only selected faces (refined question) How  to spawn particles from only selected faces on the object ?

I want to select only a few faces which spawn particles?

I selected vertex group but still does spawn from all faces. I set this Group under the field weights in partile settings. I want it to spawn from only selected ones (yellow).
Vertex groups works with vertices and as you can see when I try to select what you have in yellow by using vertices it covers the whole mesh. So what I would do is add 2 loop cuts. . When I apply the vertex group as density for the hair I get  your intended goal.