It seems remarkable: Joni Mitchell, the quintessential young thing of the sixties who summed up the ideals of a generation in the "Woodstock" anthem, is now 39 years old and back on the road.

She was in Tokyo last week for the first overseas stop on her tour and was pleased with the enthusiastic reception from Japanese audiences who cheered and sang along ("We were told they would clap politely"). She was fighting off a bout of bronchitis and characteristically laconic about her future as a middle-aged rock and roller.

"I don't have to jump in the air or anything and I've got as much creative energy as I ever had which puts some bubblegum in the pipes. You know, we started all this propaganda and now we have to eat it. I'll still be writing good songs in 10 years, although music might be far out by then... but I can spend more time painting. Look at Picasso: he was attractive to old age. I would have paid to see him!"

Ms Mitchell has returned to the rock beat after several years of delving into modern jazz. "There is a more exciting me in music at this time, more sophisticated chords: I really like the rhythm section of the Police, that clarity and simplicity, and Steely Dan."

She said the jazz phase was educational, an adventure in the classical idiom of American music, "but I didn't want to become the curator of a tradition I didn't naturally inherit".

As the rhythms of her music have settled back into a rock backbeat, the lyrics have also come simpler.

"Many of my songs are in the first person, but often, as on 'Mingus', I was writing for someone else, but people want to forget that. Those songs are universally biographical. When a song is being performed or when you hear it on a record, you have to feel it poke into your own life."

She once wrote that those early songs were about "what women think in the confines of their rooms at night". Now she sharply rejects the idea that love is anything like a woman's whole existence. The kind of love she chronicles now is best summed up by St Paul's essay on the subject, set to music on her latest album, 'Wild Things Run Fast'.

"It is very contemporary when the archaic references to burning bodies are eliminated," she siad. "It says you could have everything, wit, talent, be smart and cool but you're nothing if you don't have love."

Ms Mitchell's existence is now dominated more by painting. At one stage 'Wild Things Run Fast' was to be the last album and she was to concentrate on art. Now, despite having returned to music full-time, she is preparing for an exhibition of her work.

"I've been in a few group shows, but I'm not looking for any remuneration from it. It's a nice hobby, but I'm reluctant to open it to any kind of career, as the art world is a highly elaborate, constituted game where women have to be twice as good as men. Crossing over from another profession is an added strike against you too."

She thinks female musicians have an easier time of it. "There is a kind of cyclical equal opportunity in the music business. Now there are more women's voices on the radio, that's the sound of the early eighties, while in the late seventies popular music was dominated by men."

The main problem seems to be the lack of time to get involved in all the artistic ventures she might like. "I've got a book I want to write, films... all my dreams are artistic, fantasies of things I want to do." It all sounds exhausting, but she she "wouldn't do it any other way. Like people who know they're athletes have to go and be athletes."

She said the creative thrill was not an intellectual one. "The magic comes from spontaneity. It's a process of constantly fluctuating choices. You hear something and like it, but if you think about it and analyze you produce a stiff copy. Every one is made up of things they like and don't like and those things pour through you and come as a sort of hybrid. The intellect slumbers while that happens. But, then, it's useful as a critic - you can stand back and say, yes, it needs blue in that corner, and that's too..."

"It's a fine line there. Often with the most beautiful things, you don't know what you've done. You'll play the guitar and make a mistake and it's magic."

A lot of this hybrid influence springs from the United States, where she has buried herself in black musical culture and absorbed color from the "melding of cultures, energy and experimentation" she finds there. She originally came from Canada.

Joni Mitchell will play at the Palais on Wednesday 16 March and Thursday 17 March, and at the Melbourne Concert Hall on Monday 21 March.

Tickets are available through BASS.