Google went green and so did dozens of comic strips while President George W. Bush planted a tree on Tuesday to mark Earth Day, an environmental event that has become increasingly political and corporate.

Thirty-eight years after Earth Day began as a series of grass-roots "teach-ins" about environmental conservation and pollution, April 22 has become an occasion to focus attention on human-generated climate change and the policies around it -- a topic not on the public mind in 1970.

The method for getting the message across has certainly evolved. Google.com's online search site featured a lush logo with letters made of moss-covered boulders, a tree sprouting from the "L" and a waterfall flowing beneath it. Clicking on the image led to a list of Earth Day-related sites.

(Article continues below)

The comics pages in many U.S. newspapers featured strips with environmental themes. "Zippy The Pinhead" was typical: the short-sighted residents of Dingburg save the Earth by packing dirt into suitcases and keeping them in a storage locker.

Bush was in New Orleans for the so-called "Three Amigos" summit with leaders from Canada and Mexico, where the U.S. president planted an oak tree in Lafayette Square -- a symbolic replanting of the some 250,000 trees stripped away from the city by 2005 hurricanes Katrina and Rita.

Full article here.