HELENA, Mont. (AP) _ What the Silicon Valley is to computer chips, Montana's Bitterroot Valley is to hand-hewn log homes.

More logs are peeled, shaped and shipped from log yards in southwestern Montana, say industry spokesmen, than from anywhere else in the country.

They turn up alongside ski slopes and blue-ribbon trout streams throughout the country. Their appeal has even gone abroad. Japan has a few; so do Poland and Germany. Even Russia has its own Montana-made cabin.

``Twenty-five years ago, people asked me if this was a fad,'' said Ken Thuerbach, owner of Alpine Log Homes in tiny Victor, Mont. Twenty-five years later, Thuerbach said his business has never been stronger.

The log home industry in the West has matured much like the homes themselves, from the modest shelters of settlers to grand, palatial lodges built by increasingly sophisticated craftsmen.

While environmental challenges have battered traditional timber cutting, and jobs have dwindled, the log home industry has grown from a curiosity to a force in the industry.

And Montana's abundance of dead and seasoned lodgepole pine, still standing tall in the forest a decade or more after dying, provides just the type of log most builders covet, drawing the craftsmen to the Bitterroot Valley.

Charles Keegan III, a forest products specialist at the University of Montana, said more than 10 percent of Montana's forest products work force now builds log homes or harvests the raw material. Sales this year are expected to top $60 million on the wholesale level.

In a recent national survey of manufacturers, Log Home Living magazine found sales of $897 million in the past year, more than double the volume in 1988. John Kupferer, publisher of the magazine, said about 22,000 log homes were built in the past year, or roughly 5 percent of the single-family, custom-built housing market.

Perhaps Log Home Living's own circulation growth offers the most telling story. It sold fewer than 13,000 issues during its debut year in 1984; today, it sells 132,000 per month.

Thuerbach sees the emotional satisfaction of a log home as a prime mover behind the market.

``The more technology there is, the better it is for log homes,'' he said. As Thuerbach explains, the profusion of cell phones, faxes and computers generates a desire for something simpler.

With a log house, the owner doesn't have to guess what's holding up the roof _ the structure reveals itself. Log homes, in this sense, are not just comfortable; they're comforting.

``I really suspect there's a deep psychology here,'' said Lynne McNamara, a retired interior designer, of the pleasures of her Aspen home. ``It stimulates creativity to live in a log house.''

``I don't particularly get attached to inanimate objects,'' said Dave Meadow, who retired from Wall Street seven years ago to the Bitterroot Valley, of his 6,000-square-foot log home. ``But I certainly feel stronger about this home than I do my other homes.''

``A log home is a dream home,'' said Tom Kupferer, brother of John and publisher of Building Systems magazine, a trade publication. ``People who are interested, are passionately interested. It's like a cult.''

If it's a cult, then it's a well-heeled cult.

``I'm not building any for newlyweds,'' deadpanned Thuerbach. ``They are the Mercedes Benz of housing.''

Thuerbach said the basic log home costs about 10 percent to 15 percent more than a conventional frame house of the same size. But log home purchasers tend to be what economists call price-insensitive _ cost is not an issue.

And the cost per square foot of the finished log home, Thuerbach said, far outpaces the frame house because of all the fancy doodads and custom work demanded by the buyers.

Field stone fireplaces, slate counter tops, trellises and trestles _ all this luxury package gear is generally standard with the handmade log home. Extras, in this line of construction, really mean extras _ the indoor basketball court for one sporty Texan. Or the lap pool, or the stable, or the training room, or the media room, or the observatory.

And there's another, less visible expense. Log homes may look warm and cozy, but thermal studies show logs are not great insulators.

``In the winter, the heat goes in one direction _ out,'' said Tom Gorman, a professor of forest products at the University of Idaho. ``They would actually be better performers in the desert.''