Here's a pic from a play (of Alice IN Wonderland) I saved it for doing up scary trees in my livingroom black light forest (pics to be posted soon) But heres an idea ...

Im taking refridge cardboard boxes, paiting black and strips of brown on the trunks for depth...mine will be inside but if outside I read you can paint over with boat varnish (or sim) and it will keep the cardboard good for at least the month of Oct . Hope that helps. See my page for more AIW pics and ideas, Ani (aka the White Rabbie)