With its trove of performers, writers, directors and designers, California has always seemed as if it should be alive with theater.

But Californians generally shake their heads and deplore the lack of it. The notion persists that somehow the nation's most populated state is a theatrical backwater.

The opposite is true. Theater booms along the West Coast, from Seattle and Ashland down through the rich valleys of the Golden State to La Jolla and San Diego.

While it is unfashionable today to mention the past, 19th-century miners alertly prompted famouos Shakespearean players performing in their camps and at its zenith, San Francisco's Barbary Coast gloried in a theater where the dramas of Sir Arthur Wing Pinero were acted in the nude.

Reflecting today's avtivity is Equity's first regional office outside New York, headed by a former performer alert to the need for imaginative variations in the union's regulations, Edward Weston has had the satisfaction of seeing Equity professionals seep from Coronado up to Anchorage.

Predictably, sprawling Los Angeles is the liveliest area. There are the large stages for touring attractions of the Dorothy Chandler Pavilion, the Ahmanson, the Shubert, the Huntington Hartford, presently held by "Pal Joey '78" "Pippin," "Sly Fox" and "Colored Girls." Tony-winning Mark Taper Forum has an original with factual, local roots, "Zoot Suit." Ubiquitous "Annie" will soon move in from San Francisco.

San Francisco glories in Bill Ball's ACT - American Conservatory Theater - and across the bay the Berkeley Repertory Theater is rep and will travel.

There are more than 40 small theaters and workshops in the Los Angeles area, where new plays on offbeat topices vie with Beaumarchais, popular musicals and "Dracula." College and dinner theaters dot the sprawl.

Despite a fire this spring, San Diego found a way to continue its Globe Theater company.

But the strongest indication of this passion for live players lies in more unlikely places.

Say "Shakespeare in Visalia" to an urban Californian and he chortles in contempt at what he considers rural madness. Mention a community college in Santa Maria as a rival to East Coast experimentation and you'll find Californians vague about just where Santa Maria is.

Yet the throb of the future could well lie in what's happening in Visalia and Santa Maria.

It seemed entirely natural, one recent weekend, that California, which spawns quiz shows to the universe, should stage a unique quiz show variation for a single, remote, live showing.

Its $64-million question was "How can California create a Shakespeare Festival in this remote settling and make it internationally recognized as the best."

The place was Visalia, in the rich, rural San Joaquin Valley, a valley which, as one farmer put it, "can feed the world." Visalia is the county seat or, as they say in Tulare county, its "capital." The town's population is about 38,000, the area's roughly 75,000.

The participants included national experts on art, education, finance, city planning, public relations and politics. They came from all over the nation to wrestle with the question for three lively days.

The co-chairmen, Oscar-winning actress Beatrice Straight and actor Richard Chamberlain, had corralled such names as "Star Trek's" William Shatner, a serious and amusing amn; Equity president Theodore Bikel; Arena Stage's Tom and Zelda Fichandler; the Folger Library's John Andrews; Seattle's Duncan Ross; and actress-producer Martha Scott.

There were others, including theatrical lawyer Steven A Martindale of Washington; the Theater Development Fund's Hugh Southern; the Brooklyn Academy of Music's Bernice Weller; director Edward Payson Call; the Vail Corp's Dave Mott; consultants Bradley Morison, Ralph Bugard and Gary Phillips; American Theater Association President Jean Korf, designer Harry Honer, writer-director Curt Stodmak and Tommy Roberts of Watts.

The visiting participants broke into nine panels each making a brief statement of personal beliefs, then taking on questions from the floor.These ranged from basics to sophisticated details.

Finally, at a plenary session, "answers," or what a more formal convention might dub "resolutions," were formed under the spirited guidance of Kenneth Crosby, president of the Washington Performing Arts Society. These conclusions now are being studied by the locals, who hope to develop an action program suited both to dreams and common sense.

How did this started in Tulare County?

A wealthy Califronia, visiting Ontario's celebrated Stratford two summers ago, asked "Why can't we have this in California?" of David Fox-Brenton, a young American acting with the Strafford company. "You can if you care enough," Fox-Brenton replied.

Sniffing interest, Fox-Brenton explored the San Joaquin area and interested leading Visalians. They contributed such basics as office space, furniture, tranportation and willingness to learn. For name value, Fox-Brenton captured British actor Anthony Quayle, with whom he had been associated at the Knoxville Theater of the University of Tennessee.

Quayle, once head of England's Stratford, defined the problem with two answers: the slow approach, which led to the present status of Britain's National Theater and the Royal Shakespeare Company, or "go whole hog from the very start."

He urged the latter: "From the word go, if your enterprise is to succeed, I believe you must have a center which excels from the very start - artistically, architecturally and in every other way - so that it becomes an immediated magnet, drawing audiences (and therefore also able to accommodate them) from all over the United States andindeed the world." Quayle won a contract as artistic director on the strength of his glowing vision.

Quayle's demands for instant splendors of art and artifice and the concomitant need fro millions of dollars may have fired imaginations in the San Joaquin Valley, but most of the visiting experts couldn't have agreed less.

Absent because he was performing in London, Quayle may have been at a disadvantage, but he also avoided explaining just how to perform quick miracles and why his Tennessee venture had not been a roaring success.

The Oregon Festival's William Patton traced how its present status had the most modest of starts 43 years ago. The Fichandlers laid out how long it had taken for Arena Stage to mature. Veterans of the Lincoln Center Wars, Jules Irvine and Alan Mandell, and of ACT's homeless years, Charles Dillingham, warned of too flahy a start.

But the prime example came from Tom Patterson, the small town newspaperman who had dreamed up Ontario's Stratford and seen it grow from tent to the continent's most exciting theater. Patterson served as coordinator of the conference, with National Repertory Theater's Michael Dewell, and Patterson's name, more than any other, had stimulated acceptances from an impressive covey of national names.

To an outsider it seemed curious that the Visalians knew so little about a California organization a few hundred miles south. Santa Maria was hardly mentioned.

Here, stemming from a mere two-year community college, one finds the first American production of Thornton Wilder's "The Alcestiad" and the premiere of "Judas," by Robert Patrick, who wrote the internationally successful "Kennedy's Children."

Both these plays demand from audiences some knowledge of the Greek classics and the New Testament. They are the sort of plays which should intrigue New York's choosiest intellectuals but they have needed a less tumultuous atmosphere for their staging. One can be sure, however, that both these rich, engrossing plays will be done again and again in the new American theaters across the land.

Behind these two firsts is a Texan named Donovan Marley, who , passing through the Santa Ynez valley after service in bleak, wartime Korea, gasped at the beauty of the February land. He wrote the school system, seeking and getting a teaching job. Shortly afterwards, the system superintendent, Walter E. Conrad, was appointed to head Santa Maria's Allan Hancock Community College. Warning Marley that he could promise neither space nor staff, Conrad offered Marley the challenge of starting a theater department.

Beginning 14 years ago with "The Trojan Women," Marley has built up both a department and an audience. The Pacific Conservatory of the Performing Arts at Hancock consists of 90 carefully chosen students (out of the college's 8,000 area students) and a staff of 24. Through Equity's special actor-teacher contract, Marley has a rotating staff of professional performers, directors and designers to head what now is a company of 240 workers. This year they have presented 17 productions in three theaters to over 100,000 patrons.