When writer Doug Green fell in love with the cowboy music of Gene Autry and the Sons of the Pioneers, he realized that his enthusiasm for the plaintive harmonies and quaint evocation of the Old West was an acquired taste. So, when Green formed his own singing cowboy trio, Riders in the Sky, he relied on broad vaudevillian parodies of cowboy movies to build the group's popularity. Ranger Doug (Green), Too Slim (Fred LaBour) and Woody Paul were so funny that the gambit worked.

As the Riders have solidified their reputation through constant touring, Green has increasingly let the songs stand on their own merits without humor. The Riders' third album, "Prairie Serenade," clearly emphasizes music over humor. Traditional cowboy music is still an acquired taste, but the Riders in the Sky make the best possible case for it. Their crisply understated arrangements evoke less matinee nostalgia than the undying American mythology of the unfenced, unsettled West.

Green and Paul are the best cowboy songwriters since Marty Robbins. Green's Mexican-flavored "Old El Paso," Paul's lonesome ballad "Utah Trail" and the three-part harmony yodels on "Blue Shadows on the Trail" all make this record an appealing throwback. ON RECORD ON STAGE THE ALBUM

RIDERS IN THE SKY -- Prairie Serenade (Rounder 0170). THE SHOW

RIDERS IN THE SKY. Saturday and Sunday at the Birchmere (where the Riders will be recording a live album).