The original banjo player in the progressive bluegrass band New Grass Revival, this Kentucky picker was known for whipping off solos in the five minutes and plus range in which it seemed like every possible permutation of the notes available on the instrument would be presented. Johnson began playing guitar when he was seven, but the banjo came into his life much later, when he was 25. One of his first and greatest influences from the old-time and bluegrass camp was Ralph Stanley, leader of the Clinch Mountain Boys. Johnson joined a bluegrass band named Poor Richard's Almanac in the late '60s, an era in which great amounts of experimentation and fence-bashing were taking place in all genres of music, bluegrass definitely included. A fellow member of this group and a man who would also become a great influence in progressive bluegrass on his instrument, was mandolinist Sam Bush. These two players hit it off and wound up splintering off to join the Bluegrass Alliance, an influential progressive bluegrass band with a huge following. Other members of this group included the talented fiddler Lonnie Peerce and bassist Ebo Walker. In 1971, the group added guitarist Curtis Burch.

In the following year there was yet another shifting of planks in the platform. With the Alliance on hiatus due to Peerce's poor health, the trio of Johnson, Bush, and Burch put together a new group named the New Grass Revival. Johnson recorded several albums for Flying Fish with New Grass and continued touring through the '70s with the band, during which time the group was also pressed into service as a backing band for Leon Russell. Coming down from the Mt. Olympus of being a rock star, Russell was switching over to more of a bluegrass repertoire in an attempt to leave the image of a drunken, swaggering Joe Cocker behind him. Johnson left New Grass in 1981. If a player can be judged by what kind of talent it takes to replace him, then it can be considered a tribute that the group brought in a young, talented upstart named Bela Fleck to be the new banjo player.

Johnson was mostly a freelance player after this, appearing for example on the lovely Doc Watson collection entitled Memories and jamming with Fleck at the 1992 Tennessee Banjo Institute. He was diagnosed with lung cancer in 1996, and a large scale charity tribute to him was held in Nashville a few months later. ~ Eugene Chadbourne, Rovi