I used cheap fleece blanket throws on my layout. They had a brighter green, but I preferred the olive green as a somewhat more "realistic" color choice.
The roadbed is cut from 1/8" hardboard (actually scraps of paneling turned over) and painted gray with craft paint. Extra ties are balsa painted dark brown. After years of dealing with died sawdust, ground foam, tiny ballast and glue I did not want to deal with any of that on this layout.