Of course Dolly Parton knew that singing Stairway to Heaven would shock folks. That's one of the reasons she recorded it.

"I did it for the reaction," says the 56-year-old country singer, who recorded the hoary Led Zeppelin classic-rock epic for her new album, Halos & Horns.  "Everybody's scared to death to do it, and at my age, I thought, 'Well, why not?'  If I had just really sucked, I would've left it off the CD."

Stairway to Heaven isn't the first rock song that Parton has done bluegrass-style.  Earlier this year, the singer collected her seventh Grammy Award, thanks to an acoustic cover of Collective Soul's Shine.  Parton adds that Carl Dean, her reclusive husband of 36 years, likes to hear her work her mountain magic on rock songs.

"He loves rock and bluegrass," she says.  "He doesn't really like much in between.  He's always loved Lester Flatt and Led Zeppelin.  You wouldn't believe the stuff I hear in that house."

Parton will spend more time than usual out of the house this summer:  She kicked off her first tour in 10 years July 10 in New York.  Next, she'll head to Dallas, Los Angeles and Las Vegas.

Backed by an acoustic group of musicians, Parton relies heavily on music from Halos & Horns and the two previous bluegrass albums (though likely not Stairway to Heaven) in her set.  "We're going to do medleys of all the big hits that people like, but done our way," she says.  "We'll do things like Jolene.  We do 9 to 5.  It lends itself so well to the mountain (arrangement)."

One song from Halos & Horns that Parton hasn't yet figured out how to stage is These Old Bones, a gothic tale of a young woman and an aged Appalachian soothsayer.  Parton sings in the voices of both characters:  For the clairvoyant's voice, she assumes a creaky, nasal tone that she says imitates her mother.

"All my brothers and sisters say I'm so much like mama that it's scary," Parton says.  "And my mama, she sounds like that.  She's not in great health right now, or I would've asked her to have done it."

Parton also identifies with the old woman in the song.  "I am very psychic myself, to the point of where that's how I know all these crazy things I write about," she says.  "These old crazy women, it's just about people like us, like my mother.  If I hadn't have got out, being the way that I am, I would've been considered one of those crazy old loons in the mountains, just because I was different and because I would've had my nose in everybody's business."