Since Willie Nelson’s Fourth of July Picnic moved to Circuit of the Americas five years ago, certain elements of the iconic event have remained constant. The heat is a given. Afternoon sets from three-named pals such as Ray Wylie Hubbard and Billy Joe Shaver are a sure bet. And if you want to see Willie himself, you’ll need to stay till midnight or beyond.

But every Picnic is a little different, too. Last year’s two surprises were an afternoon rainstorm that carved a couple of hours out of the schedule and a Beto O’Rourke cameo during his 2018 U.S. Senate run. So what’s in store for 2019 that we haven’t seen before?

One intriguing focal point is the music of Guy Clark. The native Texan songwriter died in 2017 at age 74, but his legacy seems to have grown since he’s been gone. Willie’s new album, “Ride Me Back Home,” features two Clark songs: “My Favorite Picture of You,” the title track to Clark’s final album, and “Immigrant Eyes,” an older tune that’s suddenly very timely again.

Clark played Willie’s Picnic just once, in 1974, though he was in attendance at the 1972 Dripping Springs Reunion that gave rise to the annual Picnic extravaganza. But those attending this year’s Picnic will get to hear a bunch of Clark’s songs from Steve Earle, whose latest album, titled “Guy,” is a tribute to Clark.

RELATED: Austin remembers Guy Clark as one of the best-ever Texas songwriters

It made sense that Earle would record an album of Clark’s work: A decade ago, Earle released a similar tribute to Townes Van Zandt. Clark and Van Zandt were close friends, and they befriended Earle in his younger days.

“They both took an active interest in me,” Earle said in March, when he was previewing some of the material from “Guy” during the Luck Reunion on Nelson’s ranch west of Austin. “Neither one of them would have probably admitted that they took an active interest in anybody. But Guy hounded Pat Carter until Pat signed me to my first publishing deal.”

Earle remembers an outtake from the landmark 1975 documentary “Heartworn Highways” when Clark was urging folks in the room to listen to a song Earle was playing. “That was not an isolated incident,” Earle says. “He did that with me, he did it with Rodney (Crowell), he did it with a few other people.”

Crowell will be among the special guests joining Earle when he performs songs from “Guy” for an episode of the PBS television show “Austin City Limits” on Tuesday. (The taping, which also features a set from Austin singer-songwriter Patty Griffin, will livestream on the Austin City Limits YouTube channel starting at 8 p.m.)

I ASKED EARLE if it was hard to choose the 16 songs that ended up on “Guy” from a lifetime’s worth of Clark songs. “It would have been if I had tried to be fair and balanced about it,” he said. “But I finally decided, it’s my Guy Clark record, I should just do the stuff that I’m most connected to and that I knew.”

Some were probably obvious choices. “L.A. Freeway,” “Desperados Waiting for a Train” and “Heartbroke” are all well-known from versions by Jerry Jeff Walker, Ricky Skaggs and others. (And Nelson cut “Desperados” with Waylon Jennings, Johnny Cash and Kris Kristofferson on the 1985 debut of country supergroup the Highwaymen.)

But Earle dug deeper at times. “The Ballad of Laverne and Captain Flint” is a lesser-known track from Clark’s 1976 album “Texas Cookin’.” And he recorded “Don’t Let the Sunshine Fool Ya” — which appeared on a Van Zandt record but never was released by Clark himself — for a Record Store Day 7-inch that supplements the “Guy” album.

Earle and his band the Dukes — Austinite Ricky Ray Jackson, former Austin residents Eleanor Whitmore and Chris Masterson, and rhythm section Kelly Looney and Brad Pemberton — gave a full-on rockin’ treatment to “Out in the Parking Lot,” a song Clark performed acoustically. And the album-closing “Old Friends” fittingly features vocal cameos from several musicians Clark held near and dear: Crowell, Jerry Jeff Walker, Emmylou Harris, and Terry and Jo Harvey Allen.

Terry Allen, who’s also scheduled to appear on Earle’s “Austin City Limits” taping Tuesday, was given an unusual task from Clark near the end of his life. Allen, highly renowned as a visual artist as well as a songwriter, has been working on a sculpture that incorporates Clark’s ashes. The back cover of Earle’s album is a sketch for that sculpture.

Earle says Allen has now finished it. “You’re not going to see it until it finds a permanent home,” he adds. “Its location is secret because, I don’t know, he’s worried somebody will (expletive) with it. But it’s going someplace — someplace in Texas.”

Earle’s tribute record, and the two Clark songs on Nelson’s new album, are just part of what appears to be a significant increase in the presence of Clark’s work since his death. Two other Texas greats included his songs on new albums last year: Jerry Jeff Walker recorded “My Favorite Picture of You” on “It’s About Time,” and Asleep at the Wheel did “Dublin Blues” on “New Routes.”

RELATED: Asleep at the Wheel is back with a splendid new record

“Dublin Blues” — with its ATX-centric opening line, “I wish I was in Austin, at the Chili Parlor Bar” — also turns up frequently in the live sets of Pat Byrne, an Irish singer-songwriter who moved to Austin earlier this year. Byrne learned it from local pianist Chris Gage, who often plays the song during his Monday-night residency at Donn’s Depot.

A KEY FIGURE in Clark’s heightened visibility is Tamara Saviano, who wrote the Clark biography “Without Getting Killed or Caught,” published by Texas A&M Press in 2016. “I hope that it just continues to grow,” said Saviano, who noted that Austin troubadour Joe Ely has recorded but not yet released his own album of Clark songs. “I think of Guy like Shakespeare — that 100 years from now they’re going to be teaching it.”

Saviano, who lives part-time in Austin, is also working on a documentary film about Clark’s life that she’s hoping will debut at the South by Southwest Film Festival next year. Sandra Adair, Oscar-nominated editor for Austin filmmaker Richard Linklater, is helping to get a rough cut of the film ready for SXSW submission by this fall.

Saviano’s film will be a documentary — not part of the current biopic trend with movies about Elton John, Queen and others — but it will have an intriguing twist: The film will be told from the perspective of Guy’s wife, Susanna Clark, with narration taken directly from Susanna’s diaries.

Susanna was a well-known songwriter in her own right, and also an accomplished painter. Here’s where another connection to Willie comes in: The cover of Nelson’s multimillion-selling 1978 album “Stardust” features one of her paintings on the cover.

Saviano says she was overjoyed when she heard Nelson had cut two of Clark’s songs on “Ride Me Back Home.” “And especially those two,” she stresses. “‘My Favorite Picture of You,’ to me, is Guy’s last masterpiece that he wrote and recorded. And ‘Immigrant Eyes’ is perfect for right now.”

Released on Clark’s album “Old Friends” in 1988, “Immigrant Eyes” — written with Roger Murrah — indeed resonates deeply amid current controversies over the treatment of those seeking asylum at the Texas border. It’s no surprise that Nelson chose this song, given his statements in 2018 when President Trump’s policy of separating children from their parents first stirred up a firestorm.

“What’s going on at our southern border is outrageous,” Nelson told Rolling Stone in June 2018. “Christians everywhere should be up in arms.” With "Immigrant Eyes," he put his politics where his music is: “Some were one desk away from freedom, some were torn from someone they love,” he sings in verses that harken back to the Ellis Island immigrations from Europe a century ago.

AMY NELSON, WILLIE'S DAUGHTER and a member of the Austin duo Folk Uke, directed a video for the song that was released last week. Willie speaks words inscribed on the Statue of Liberty as the video opens: “Give me your tired, your poor, your huddled masses, yearning to breathe free.”

When her father first played the song for her a few months ago, “I was like, 'Dad, you’ve got to do a video for this one, because it totally reflects the times that we're in right now,'” Amy recalls. “He said, ‘Why don't you do it?’”

 

She wove together various sources of film for the video, including shots of her father singing and playing guitar, historical clips from the Library of Congress and footage from rallies she attended at the Texas Capitol last year and at a South Texas detention center in 2015.

Participants in that 2015 demonstration, organized in part by Texas organization Grassroots Leadership, called for a shutdown of what was then the largest immigration detention center in the nation. “I felt that was a  s sad as it could get. I had no idea where we were headed,” Amy says.

Amy will also perform at this year’s Picnic with Folk Uke, which includes Cathy Guthrie, daughter of folk singer Arlo Guthrie. They’ll play a short set on the main stage during a set change before Jamey Johnson’s performance.

Folk Uke’s material centers on humor rather than politics, but Amy said she might use the occasion to raise awareness about immigration issues. After O’Rourke’s appearance at the 2018 Picnic, the door seems open for more activism at the Independence Day event.

“Dad doesn’t get on the soapbox very often; he usually just does his show,” she notes. “But maybe I'll say something. I’ll try to get people to support Grassroots Leadership, because they are doing some amazing stuff.”

If nothing else, she points out, Clark’s “Immigrant Eyes” speaks for itself. “I'd never heard Guy sing it until after Dad recorded it,” she said. “We're hearing it with different ears today, now that this reality has set in.”

LISTEN — Peter Blackstock talks about Willie's Picnic on Austin360 Radio: