MLINDBERG: If you want the general image of the layout photo you posted, then you are on the right track for a "display-toy train layout".
Just look for trees that you think look good. Buy a dozen trees at a time...they will disappear fast when you start "planting" them.
I know some guys who take asphalt shingles (like for a home) and use them as material for their roads. They lay them in place, mark them with magic marker for trimming to "road width" including turns and curves and intersections.
You can purchase plaster coated gauze to use for scenery (or to put a cast on that broken finger where you hit it with the hammer). If you do that, pick up some latex paint in small containers (squeeze tubes and small squeeze bottles at the hobby stores)...Oh, no, not for the finger cast, for the hill side or mountain you decide to build out of a pile of newspaper and the wet plaster/cloth. Paint it the color of "earth and grass" that YOU like.
There are lots of methods to expand your toy train/display layout scenery. Who knows? You may end up liking realistic scenery so much that you pull up the carpet and use real dirt with ground foam and ground cover. I am moderately satisfied with painting the Homasote and spreading ground foam and ground cover in the wet paint so it holds it to the surface. Granted, I do multiple layers of that...and sometimes follow up with a spray coat of "wet water" (a spray bottle of water with a drop or two of dishwashing soap and some matte medium or Elmer's glue to help soak the ground cover and to help hold it in place).
I used a lot of lichen balls for trees in HO, but they would work "adequately" as brushes and scrub trees "down in the boondocks" (That's the side of town...Uhhh...thank you Billy Joe Royal)
Let's see...advice about roads and trees and wet water spray and plaster embedded cloth and related humor about broken finger and plaster cast....1960s song lyrics...yep, that about covers everything I can share tonight.
