how to make pine trees h0 spruce forest part 2 

how to make superrealistic pine trees h0 scale finescale realistic spruce forest for my model railroad layout.
To obscure the opening in the backdrop through which my trains enter the layout, I'm building a forest. I want a forest that gives the viewer the impression of being in it. So, looking from the inside of the forest, and through the dense foliage of the forest edge you catch glimpes of the train as it enters the scene.
Treetops are important. They stand out as a silhouette against the well lit layout, so they have to be good!