Greensbury works with Ivan W. Martin, founder and owner of Natural Acres Farm (as seen with Lisa Ling from Oprah), who humanely raises animals in pastures, where they eat grass and range freely in an environment free of added hormones, antibiotics and other chemicals.

http://www.oprah.com/slideshow/oprahshow/20081008_tows_animals/5

http://oprah.about.com/od/oprahshowrecaps/p/americanfarms.htm