Anyone still dreaming of a Led Zeppelin reunion should know this: Robert Plant once made a pledge to KBOO when he heard someone at the independent Portland station say they would never play "Stairway to Heaven."

The story says everything about who Plant is as a person and a musician. He knew that somewhere in the U.S., "there's gotta be a place that rains as much as my home on the Welsh borders." He was driving from Portland to Lincoln City, planning to take the coast highway to Eureka, just "exploring this beautiful land" and listening to KBOO. Someone at the station was playing the Jive Five, a Sixties soul group, and Plant was loving it. Then, during a pledge break, a challenge was thrown out: send us some money, and we'll never play "Stairway to Heaven" again. Plant pulled over and pledged $1,000 -- and he wrote the lyrics to the song!

"It's not that I don't like that song," Plant said at the SXSW music festival in 2005. "It's just that I've heard it before."

When Plant comes back to Portland on Tuesday with his new group, Band of Joy, he'll play a few Zep classics, but they'll be blues-ed up and run through Nashville and the Mississippi Delta by the man who titled one of his recent albums "The Mighty Rearranger." Plant is an Americana artist now, not a heavy metal dinosaur, and just because he's been opening with "Black Dog" and mixing in "Black Country Woman," "Houses of the Holy," "Tangerine," "Ramble On" and "Gallows Pole" doesn't mean he's cashing in on his past.

Far from it. He's left millions and millions of dollars on the table (guarantees for a Led Zeppelin reunion tour reportedly approached $200 million) because he'd rather challenge himself and play something fresh, first with Alison Krauss and T Bone Burnett on the "Raising Sand" album and tour and now with a band that includes alt-stalwarts Buddy Miller and Patty Griffin. Jimmy Page and John Paul Jones were ready to take the money and pretend it's 1977 and Led Zeppelin was playing the Kingdome; Plant walked away and moved on.
The path that Plant took from Led Zeppelin to Band of Joy can be traced on his solo album covers. In "Pictures at Eleven" and "The Principle of Moments," he's all about the Eighties, with a slick look and sound that's a half-step away from Robert Palmer or Hall and Oates. By 1998's blues reunion with Page, "Walking Into Clarksdale," it's become more about the music. By the time Plant released the underrated "Dreamland" (2002), he's disappeared completely into the songs. Plant's last four albums show him digging deeper into the American sound that's always fascinated him, working with the best producers (Miller, Burnett), casting a wide net for songs to cover (Los Lobos, Richard Thompson, Townes Van Zandt, and Low on "Band of Joy") and putting his famously strong voice back in the mix to push the music forward.

Onstage, Plant has been first among equals, singing with soul and playing the harmonica while generously giving Miller, Griffin and Darrell Scott a turn at lead vocals. Griffin just won a Grammy for Best Traditional Gospel Album for "Downtown Church," a record produced by Miller that is a wonderful indication of what the vibe is around the Band of Joy tour.