Let's hear it for the cultural heroes who always speak the truth as they know it, no matter what the cost to themselves:

NEW YORK — Three months after Bruce Springsteen persuaded Pete Seeger to sing This Land Is Your Land with him at President Obama's inaugural concert, they'll be back together on stage Sunday — on Seeger's 90th birthday.

A sold-out benefit concert at Madison Square Garden will celebrate Seeger, the folk singer/songwriter who was banished from commercial TV for 17 years.

Seeger says a party for 15,000 isn't his idea of a birthday celebration, even with more than 40 musicians, including Dave Matthews, Eddie Vedder and Arlo Guthrie, whose dad, Woody, taught Seeger how to jump freight trains 60 years ago.

But he agreed to it because it will benefit his Hudson River environmental group. Or, as Seeger puts it, "wooden boats don't last forever."

The boat is a 106-foot sloop, the Clearwater, a floating symbol for the group of the same name that Seeger started in 1966 when the Hudson was an open sewer.

It's healthier now, repopulated by eagles, shad and osprey. But, Seeger says, "a lot remains to be done," including "thousands of dollars of repairs to the boat."

Seeger, who says "small is beautiful," plans to remind the crowd: "It's not always the big things that make a difference, but all the small things done by people who don't get attention."

As the subject of three new books and an updated biography, Seeger says, "I've had too much publicity," even as he talks by phone to a reporter.

He says he's encouraged by Obama's willingness to experiment and "to remind us he can't do it all. We have to help."

He recalls how another president, Herbert Hoover, told Rudy Vallee: "If you can sing a song that makes people forget the Depression, I'll give you a medal."

Says Seeger: "Too many singers have been trying to get that medal."

He's the only star in the Rock and Roll Hall of Fame convicted of contempt of Congress for refusing to discuss past membership in the Communist Party. His 1955 conviction was overturned on appeal in 1961, but Seeger's blacklisting lasted from 1950 to 1967. Even then, CBS censored his anti-Vietnam War allegory, Waist Deep in the Big Muddy

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