im workin on building mountains using woodland scenics plaster cloth i want to add trees of course how do i do that?
Are you asking how to make trees or how to plant them?
I plant them by just poking a hole, putting a little glue in the hole and sticking the tree into it.
This may sound a little odd but I just lay them about in a clump or on their sides. If you look at real trees that are not in your yard the green parts starts at the ground level. You rarely see a trunk in this part of the country. By just laying them on the layout is also nice in the fact that is they accidentally get moved it’s no big deal.
RMax
May I suggest that you use wire window screening as a base for you plaster cloth. I then, cover the plaster cloth with Hydrocal plaster. It is very firm and will not crack, as Plaster of Paris will.). It forms a firmer base into which you plant your trees. Drill holes for most of the trees, before you paint the mountainside, vacuum up the white plaster., and then spray the mountainside with varied patches of brown and dark green. I prefer to use Scenic Express Super Trees for my foreground trees, and make the trunks from “sage”. I, then, spray the armatures with hair spray or spray adhesivs and sprinkle on Blended green Floc-foam. A drop of glue in each hole and plant the trees. Fill in the space between more distant trees with Clump Foam of varied green texture. Place a lot of forest floor debris, and fallen leaves, as you build your forest canopy. 
For narrow ridges of conifer trees, I like to cut out sheets of green painted packaging sponge, into zig-zag form, and then layer these above the ridge. Bob Hahn 
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