SAVE EARTH grow a tree

A campaign to plant a billion trees in a single year was launched at the United Nations Climate Change Conference in Nairobi, Kenya, in November 2006. The Plant for the Planet: Billion Tree Campaign is intended to encourage people and organizations everywhere to take small but practical steps to reduce global warming, which many experts believe is the most important environmental challenge of the 21st century.

illustration by oasis1
source: http://environment.about.com/od/whatyoucando/a/billion_trees.htm