'It was an appointment that changed the course of my life when I was 13 years old," says Marty Stuart.

He's talking about the first Delaware Valley Bluegrass Festival in Bear, Delaware 40 years ago. The great Lester Flatt invited Stuart, then a mandolin-playing teenager, to sit in with his band for four sets that Labor Day weekend, and after the last one, asked him to join the band.

After "a whole lot of talking" to persuade his parents, "that's how I said goodbye to my childhood," says Stuart, whose resumé now includes stints in the bands of Doc Watson and Johnny Cash and a hit-filled and critically acclaimed solo career.

This weekend, he returns to headline Saturday night of the Bluegrass Festival, now held not far from the Delaware Memorial Bridge at the Salem County Fairgrounds in Woodstown, New Jersey He will bring his band, the Fabulous Superlatives; his deep knowledge of country music; his hard-driving blend of rockabilly, honky-tonk, and bluegrass; and, in all likelihood, his flashy, rhinestone-encrusted Nudie suits.

Stuart, born in Philadelphia, Mississippi, remembers seeing many first-generation greats at bluegrass festivals around the country, artists such as Ralph Stanley and Bill Monroe (who helped organize that first Delaware Valley Bluegrass Festival).

"It was like watching characters from the Old Testament singing. It was really moving to me," he says. "As I have gone on in my life, I have carried them with me in my heart, carried their stories and their presence and their songs."

This year's festival features a delectable mix of tradition-minded musicians, including superstars, old favorites, and new discoveries. It's a place to rediscover the past, explore the present, and be inspired for the future of old-time music.

Friday's highlights include Suzy Bogguss, the sweet-voiced country star who recently released a set of traditional folk songs; the Grascals and their New Grass exuberance; and the Quebe Sisters Band, charming Texans who cross Andrews Sisters-like harmonies with Bob Wills-inspired Western swing.

Saturday brings, in addition to Stuart, longtime bluegrass innovator J.D. Crowe and current star Dale Ann Bradley, the Kentucky vocalist whose 2011 album Somewhere South of Crazy pays tribute to both Bill Monroe and Seals & Croft. Sunday features the somber narratives of Della Mae, the neo-bluegrass group from Boston; the expert gospel harmony singing of Dailey & Vincent; and the old-time string band Orpheus Supertones.

Stuart doesn't play many bluegrass festivals these days, but this 40th anniversary is an exception. "It was an opportunity too good to pass up. I just wanted to go back and touch home plate one more time," he says with a laugh.

By Steve Klinge