There are four simple rules for making it as a singing cowboy: (1) Have a nice horse. (2) Have a nice physique. (3) Have a nice face. (4) Be able to yodel.

So says Riders in the Sky's Ranger Doug, and he should know. He wrote the book on singing cowboys--literally. It's called Singing in the Saddle: The History of the Singing Cowboy, and it was the first serious attempt to document the genre.

"There was a lot of misinformation out there, and nobody had ever done the whole history," he says.

But the odd thing about Ranger Doug's rules is that his own group, which plays the Kuumbwa on Tuesday, wouldn't pass muster. There's nothing wrong with their physiques or faces, and they can definitely yodel. But there's no getting around the fact that they don't have a horse.

Or maybe there is. In his defense, Ranger Doug points to a little-known chapter in the history of Riders in the Sky. Back in the early '90s, the group had a Saturday morning show. Titled eponymously, it was CBS' replacement for Pee-Wee's Playhouse, and featured the same zany style, not to mention the same set designer and writer. Over its year-long run, Ranger Doug and his fellow riders Too Slim and Woody Paul (since joined by fourth member Joey the CowPolka King) would interact with puppets and talking cacti. The show was even filmed in the old Republic studios, home to some of the singing cowboy icons. "It was incredible," says Ranger Doug. "We were working in the same buildings Roy Rogers and Gene Autry had been in." And Ranger Doug even had a horse, whose name was "Turbo" on the show and "Pal" in real life. Thus did the show seal the deal on the Riders' singing-cowboy cred.

But just as the cultural importance of singing cowboys didn't get its full due until Singing in the Saddle, mainstream culture hasn't always "got" the Riders in the Sky mix of comic showmanship with sincere dedication to traditional Western music. Ranger Doug recalls that when the group started out in the late '70s--31 years and 5,741 live appearances ago--no one believed they could pull off a fully acoustic tribute to real Western music.

"Everybody said, 'You gotta add drums.' We said, 'No, we don't want to do that.' They said, 'What, you don't want to work?'" he remembers.

But work they did, and in a matter of months they had already broken onto the influential Austin City Limits.

Ranger Doug credits bluegrass great Bill Monroe with giving him the stubbornness to stick to his guns. In his college years, the future Riders guitarist cut his teeth playing with old-time bluegrass bands and landed a gig touring with Monroe. It wasn't always easy--Ranger Doug describes Monroe as "intimidating" and the experience as "terrifying"--but he saw how Monroe believed in the power of his own music even before he was rediscovered and elevated to legendary status. "We played a lot of crummy little places and military bases," he says, "but he believed in what he did so much. What I learned is that if you really believe in what you're doing, keep doing it."

Putting a similar faith in their own mission, Riders in the Sky did just that. "Our focus is exactly the same as it was when we started," says Ranger Doug. "We believe in keeping this dignified and poetic tradition of Western music alive." Not only have they kept it alive, but they've watched its status rise within popular culture. Their upcoming album features them performing classic Western songs with the backing of the Nashville Symphony. It's only the most recent orchestra they've worked with; others include the Boston Pops and the L.A. Philharmonic. "I always love it," says Ranger Doug of their brushes with high society. "It sounds like a Western movie. And we still have fun. We love to crack up the band."

Such high-profile cultural mash-ups are a far cry from the labor of love that was Singing in the Saddle--"We didn't threaten Anne Rice," he says of its university-press printing. But the book was a chance to delve into the history of his childhood heroes and cement their place in musical history. Though Autry, as the trailblazer that every other movie studio tried to imitate, will always be considered the most important singing cowboy, Ranger Doug admits he has some bias toward his own favorite. "I always loved Tex Ritter when I was a kid," he says, "because I thought he was more authentic in his way. And he had more fights in his movies."

RIDERS IN THE SKY play at 7:30pm ($22), and a children's show at 5pm (children $12.50/adults $16), on Tuesday, April 28, at Kuumbwa, 320 Cedar St., Santa Cruz. For tickets, contact Snazzy Productions at 831.479.9421.

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