In the this photo we have a down town scene next to the tracks.
This would be in the 1940’s – 1950’s. So this town choose to place a street next to the track but not touching. They placed rock between the track and the street to keep traffic from crashing in to trains.
The ground is not seen much but can be seen around the building is some brown with darker areas. Nest to the track is covered with foliage but not allowed to grow to high.
You should use something close to the color of natural are you are modeling. Then add some foliage and some rocks.
Now the track ballast is Empire builder so we can assume that it is somewhere from New York to Chicago to Los Angeles route.
So you should not always use the rock that match’s the local color in your scene. But in this scene we just used large Empire Builder rock.
Nature is messy and we surprise your with the weird color combos that are found in the same small area.