I don't know if this will be visible once I am done with this area, but in the center section of my layout, I had previously painted a small town scene with a building and a couple of streets. I decided that since I have a handful of N-scale people left over, I'd glue them in the scene right in front of the backdrop. They seemed to fit the painted scene perfectly.
At the end of the season we tend to cut down our grapevines. As I was cutting them, I realized that some of the straight ones might make for some nice "chopped-down" trees for my layout. Here's a longer one glued to the very front edge of the layout. In the background, on the left side of the photo, you may notice some "3D" trees. These were left over trees from my N-scale days. They make great small trees in the background, i.e. some forced perspective.
I glued a couple of shorter ones behind the creek. I used a good quantity of yellow carpenter's glue to glue them to the layout's scenery base. I then added some more glue to represent the roots near the base. These were later painted a flat black. I plan to go back and dry-brush the "roots" with white paint to make them more realistic. The idea behind these tree stumps is that the trees became too big and were a danger to the railroad, so they were cut down.