Joni Mitchell has released Blue 50, a five-track digital collection of outtakes and demos from songs off her acclaimed 1971 album Blue, which celebrates its 50th anniversary tomorrow.

The EP includes a rare recording of "Hunter," a song released only on the 2009 album Amchitka, which was recorded live at the 1970 Vancouver Greenpeace benefit with James Taylor and Phil Ochs. Blue 50 also contains alternate versions of album tracks “River” and “Urge for Going,” as well as early demos for “California” and “A Case of You."

Now lauded as one of the greatest albums of all time, the deeply vulnerable Blue, which showcased several songs written about Mitchell's breakup with Graham Nash, waded into uncharted singer-songwriter waters at the time of its release.

“The most feedback that I got was that I had gone too far and was exposing too much of myself," Mitchell recently told writer and director Cameron Crowe in a rare interview. (Mitchell suffered a brain aneurysm in 2015 that left her temporarily in a coma.)

"I couldn’t tell what I had created, really," she continued. "The initial response I got was critical, mostly from the male singer-songwriters. It was kind of like [Bob] Dylan going electric. They were afraid. Is this contagious? Do we all have to get this honest now? That's what the boys were telling me. 'Save something of yourself, Joni. Nobody's ever gonna cover these songs. They're too personal.'"

Blue is also being remastered as part of an upcoming box set featuring Mitchell's first four albums. That collection is due July 2 and will be followed by the five-disc Joni Mitchell Archives Vol. 2: The Reprise Years (1968 to 1971) on Oct. 29. That set includes previously unreleased live and studio tracks that chart Mitchell through a transitional period.

"I'm the same person," she said. "It's all still very present for me. I mean, I've changed styles and things, but not the core of who I am, ever. My old friends see me as being the same as I was when I was a teenager, and so do I."

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Individuality set her apart from other singer-songwriters in the '70s. 

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