The big noises, the stars, of the ninth annual Mariposa Folk Festival, which opens next Friday on Centre Island and carries on through the weekend, are Ian and Sylvia, Joni Mitchell, Vera Johnson, Joan Baez and ....

Wait, wait. Hold on. Cera who? Who Johnson?

The name is Vera Johnson, and she is a slightly plain lady, 49 years old, with a hair style that tends to crewcut and a costume that features a billowing muu muu, white socks and sandals.

She sounds unlikely and looks unlikely, but on the basis of her reception at the '68 festival, she's a guaranteed Mariposa star. She came in from out of left field last year - well, actually from Vancouver - and, to the astonishment of everyone, specially Mariposa's organizers, she won the festival's longest and most hilarious ovation. She managed her triumph with a style that's about as subtle as her muu muu and with songs, her own, that discuss current events in direct, untrammelled, no-nonsense prose.

Consider, for example, the opening verse of her serenade to our Prime Minister.

"Pierre Trudeau is very astute.
Not only that, he really is cute;
He's got ideas and get-up-and-go,
That's why I like Pierre Trudeau."

Vera's repertoire - she whips up two or three new numbers in a good week - also includes a hymn to Che Guevara, a song about Russia's invasion of Czechoslovakia, songs on almost any subject, in fact, not excluding her own troubled marital history. She likes to help out her lyrics, and maybe it was the contrast she offered to the introspective, hushed young singers who make up much of Mariposa's program that won her the grand response at last year's festival.

Whatever the explanation for her unexpected success, Vera Johnson could only have happened at Mariposa. There's something about the homey, dedicated atmosphere surrounding the festival that encourages weird, attractive, funny events. Mariposa is not, as the recent Toronto Pop Festival decidedly was, a Big Deal, and it's the very quietness of the operation that lends it its winning charm.

Last year it was Vera Johnson. Three years ago it was Buddy Guy, the great Chicago blues singer and guitarist making his first appearance anywhere with his own band and breaking up the audience with his thrilling music. Two years ago it was Leonard Cohen's moment. He sang a marvellous set, and then, in answer to the crowd's begging calls for Suzanne, he began to sing it, his best known song. He got half into the second verse, stopped abruptly, leaned forward and said, "The guitar doesn't want to play it." And with magic grace he walked softly away from the microphone, the audience and the festival.

Joni Mitchell enjoyed her first major breakthrough at Mariposa five years ago, and moving even further back, Ian and Sylvia Tyson gathered some of their first popularity singing in the early festivals up in Orillia. Something special, something sad or funny or wonderful, comes out of Mariposa every year, and the great performers, the Tysons and Mitchell and the rest, are inevitably drawn back to it each summer, singing and playing for a crummy $75, the standard fee. The Mariposa atmosphere wins them over, and even the mighty Baez turned down the Toronto Pop Festival's offer of $10,000 in favor of Mariposa's 75 bucks.

But the same amateur quality - "amateur" in the best British sense - that involves the singers also means that Things Go Wrong at Mariposa. There are inevitably goofs in artistic planning; Buffy St.-Marie's set, which came after Leonard Cohen's spectacular performance and exit, constituted a disaster, and the Travellers following Joni Mitchell a couple of years ago created an anti-climax.

And there are financial pains, too, even with the cut-rate fees. Tom Bishop, the festival president, has chipped in almost $7,000 from his own wallet over the last couple of years to keep the operation out of debt, and the Ontario Arts Council was so unimpressed by Mariposa's financial management that it turned down the festival's bid for a no-strings grant, insisting instead that it would donate $1,500 if Bishop and the others raised $3,000 on their own hook.

Still, for all its troubles and woes, Mariposa has persisted for nine years and it's progressed a long, dignified way from its beginnings. The 1963 festival was typical of early Mariposa: Orillia police arrested 130 kids on drinking charges, and the cycle crowd from the Wild Ones M.C. and the Lancers took almost as prominent a part in the proceedings as the singers and players.

Today, 1969, everything's strictly business. No booze, no hoods - just dedicated folkie nuts. The serious stuff this year gets under way on Friday morning, and throughout the weekend there'll be a constant round of workshops, covering musical ground from the Mountain Music of Peru to Canadian Indian Syllable Songs. Joan Baez is conducting one of the workshops, Saturday afternoon at 3.30, on a topic that has so far been left open but that could cover anything from motherhood (she's expecting a baby in November) to life in an American prison (her husband, David Harris, a draft resister, is about to sample it.)

The heavyweights will appear in concert on each of the weekend's three evenings. Friday looks strongest - it features Ian and Sylvia, Joni Mitchell, Bonnie Dobson and Gilles Vigneault. Saturday offers a heavy load of American folk and blues singers (Mike Seeger, Taj Mahal, the New Lost City Ramblers), while Sunday's program includes the queen, Joan Baez.

And, oh yeah, right beside Baez on the bill that last night, there'll be this plain lady in a muu muu and sandals. Old Vera Johnson.

*Jack Batten writes on pop music and jazz for The Star.