More than 40 performers turned out to honor the legendary folk singer at a birthday concert at New York's Madison Square Garden on Sunday night. The lineup included Bruce Springsteen, Dave Matthews, Emmylou Harris and John Mellencamp. Seeger opened the show playing a flute solo called "Menomenee Love Song." The show ended with Seeger and all his guests doing an extended cover of Woody Guthrie's "This Land is My Land." Proceeds from the event are going toward preserving and protecting the Hudson River.