What about using crayons in different shades of dark yellow and light brown and just coloring all over a piece of paper? That would give you the color scheme... you could cut out strips and layer them.
I've made some pretty realistic backgrounds by using a Fiskars CardBoss and dry embossing on a lighter color (depending on what I'm trying to do) then rubbing different shades of ink over the area. I have done dry grass (lo not uploaded) and it looked dimenisional and was to scale of my pictures. I used this method on the lo below to make paper look like brick - same method, different effect.