I'm always looking for ideas and ways to decorate with natural materials. I see lots of ideas like this at Pottery Barn, but usually they are more than I am willing to spend.  I like to recreate their ideas on my budget using materials from nature or from box craft stores.

These moss balls are a great way to use materials that you can gather from the woods.  I would recommend using several different types of moss instead of just one king to create even more interest.  The moss balls are a good way to decorate with nature and would probably last around a week or so depending upon the weather conditions.  Of course, you could go wild with this idea and use many other materials and glue them on the styrofoam.  Things such as acorns, chinese chestnuts, pretty leaves, and on and on.  Enjoy creating from nature.