Dolly Parton, Linda Ronstadt and Emmylou Harris have released a new lyric video to help share a previously unreleased version of their song "Wildflowers."

"Wildflowers" was penned by Parton and originally released on her, Ronstadt and Harris' collaborative album, Trio, in 1987. This new version of the song appears on the upcoming three-album set The Complete Trio Collection.

In addition to releasing Trio together in 1987, the threesome also released Trio II in 1999. Together, the two albums sold more than 5 million copies and won Parton, Ronstadt and Harris three Grammy Awards. The new album set will feature remastered versions of both Trio and Trio II as well as a third album made up of previously unreleased songs and alternate takes that were recorded during sessions in 1985, 1986, 1993, 1994 and 1998.

“We had a lot of outtakes,” Harris, who produced the project, says. “I didn’t realize how many … And it is some pretty great stuff. I go back and say, ‘Damn, we sounded good. Why didn’t we put that one on there?’”

The Complete Trio Collection is set for release on Sept. 9. Also set for release on that date are a single-disc album, My Dear Companion: Selections From the Trio Collection, which features a mix of tracks from the three-disc set, and Farther Along, a double-LP featuring all of the bonus songs from the collection.

“We’ve been trying for years to put out the thing that we had in the can and repackage the things that we did,” Parton explains. “Emmylou has been working at this for a long time.”

The new project is bittersweet for the threesome, as Ronstadt’s ongoing battle with Parkison’s disease has left her unable to sing.

“I can’t get to the note,” Ronstadt says. “I can’t make any quality sound. I can’t arrange pitch. I might aim for a note and hit another one. It sounds like shouting.”

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