The sawdust idea is a great one. I do work as a finishing carpenter and always have a suplyy of MDF dust which is extremely fine. I saved about 3 coffee cans full and spent about a week or so dying it all with water and food coloring. Once it's dried and sifted it works great for ground cover. Anther idea for you to consider, Tucker, is dye the sawdust different shades of green and brown. It has a really nice look.