Almost as much as Willie Nelson is known for Austin, he's known for Nashville — and for subverting it. The 90-year-old singer has made an iconic, and extremely long career of conforming to and bucking against musical expectations, and now he's circled back around to tradition — without losing his own sound.

Nelson's new LP, Bluegrass, is his first album-length tribute to the traditional country genre. Yet, released on September 15, it's not even his first album of 2023. It follows I Don't Know A Thing About Love: The Songs of Harlan Howard, a tribute to the Nashville songwriter who gave folks "I Fall to Pieces."

Bluegrass, in a way, is Nelson's genre-bent tribute to his own work. The setlist gathers a dozen of the songwriter and his fans' "favorite" songs he wrote, according to a press release, re-rendered with a bluegrass ensemble.

The focus on orchestration highlights that this is a collaborative effort by the amiable, but largely solo performer. One song, "Good Hearted Woman," is the only track on the album not just written by Nelson, thanks to the similar creative genius of outlaw country great Waylon Jennings. Willie's son, Micah Nelson, created the cover art: an appropriately blue portrait of the singer with warm undertones and a wreath of familiar recreational leaves. The album was produced by Willie's longtime collaborator Buddy Cannon.

Nelson's son created the cover art — in blue, of course.Image courtesy of Willie Nelson; created by Micah Nelson

Even if a listener doesn't recognize each song on the album, Nelson's voice is as unmistakeable as ever. Against a bluegrass arrangement, it floats undisturbed and unhurried. At times, it even sounds like Nelson and the band are performing in different meters, the band bustling along cheerfully while the singer lounges around the beat — but never on it.

In fact, listeners who avoid Bluegrass may find their tune changes when listening to these laid-back renditions. "Still Is Still Moving To Me" brings the more frenetic tempo and multi-part harmonies that the genre is known for at its most ferocious; but iconic songs like "Sad Songs and Waltzes" and "Yesterday's Wine" may not even strike listeners as bluegrass if they're not listening for it — just very string-heavy traditional country tunes.

"On the Road Again," "Man With the Blues," and album-opener "No Love Around" are perhaps the tracks that benefit the most from the Bluegrass treatment. All three seem a little more cheerful, a little more upbeat, and a little more reassuring than their original forms. There's nothing warmer than hearing the iconic "On the Road Again" melody on gut strings — except perhaps listening to the country legend offer his "advice" over that plucky, self-assured backcountry orchestra.

Most important, the arrangements rework rather than rewriting the songs. None of the renditions give off an air of hokeyness or trying to shake things up; These are just great country songs that sound even better with a banjo. It makes sense that the change in instrumentation wouldn't shift much, since according to the release, Nelson decided to record the tribute because the style informed so much of his natural songwriting style.

"Using his own catalog as source material, in the spirit of traditional bluegrass sourcing hillbilly folk music, Willie chose songs combining the kind of strong melodies, memorable storylines and tight ensemble-interplay found in traditional bluegrass interpretations of the roots (from European melodies to African rhythms) of American folk songs," acknowledges the release.

By Texas Monthly'scount (shared in the release), this is Nelson's 151st album. Avid collectors can look forward to a 12-inch special edition pressed in blue vinyl, available for purchase on September 29. Preorder ($29.98) at willienelson.com.

This year the songwriter was honored with a five-part documentary series, a blowout 90th birthday concert, the naming of a prestigious arts endowment by the University of Texas at Austin, and two Grammy Awards. His book, Energy Follows Thought: The Stories Behind My Songs, comes out October 23. He will be inducted into the Rock and Roll Hall of Fame days later, on November 3.

Listen to Bluegrass on your favorite streaming platform. More information is available at willienelson.com.