The annual rite of spring, where we pay homage to the environment, got its start in 1970, the brainchild of former Sen. Gaylord Nelson, D-Wis. Now 86, Nelson still is trumpeting his environmental agenda, focusing attention now on population issues.

"If you double the population or quadruple it, then the infrastructure has to double or quadruple," Nelson said. "One hundred million more cars would be added to the roads. What does that mean? The public has a right to know where the policies are leading the country.

"If 33 years had gone by and nobody wanted to be identified with Earth Day, it would have been a complete flop," Nelson told the Houston Chronicle. "Now everybody, even polluters, wants to be identified with Earth Day and that means the whole idea has been a success."

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