@Treehugger - 34,000+ Followers
Since joining Twitter in May of 2008, @Treehugger has quickly gathered a large following for those looking to jack into its daily gush of eco-friendly content.
Obviously, having a recognizable brand, powerful parent company (Discovery), and a tightly woven network of writers helps. Contributors such as Graham Hill (@ghill), Lloyd Alter (@lloydalter), and Chris Tackett (@christackett) all work daily to not only promote TH articles, but also interact with the larger green Twitter community.
(Follower numbers valid as of November 2009)