Progressive bluegrass is one of two major subgenres of
bluegrass music. It is also known as
newgrass, a term attributed to
New Grass Revival member Ebo Walker. Musicians and bands
John Hartford,
New Grass Revival,
J.D. Crowe and the
New South,
The Dillards, Boone Creek,
Country Gazette, and the
Seldom Scene pioneered innovations in the genre. Some groups began using electric instruments and importing songs from other genres, particularly
rock & roll. Progressive bluegrass became popular in the late 1960s and 1970s, but it can be traced back to the
banjo and
contrabass duets that
Earl Scruggs played even in the earliest days of the
Foggy Mountain Boys. The four key distinguishing elements of progressive bluegrass are (1) instrumentation, frequently including
electric guitars,
drums,
piano, and more, (2) songs imported or styles imitated from other musical genres like
jazz,
rock and others, (3) non-traditional chord progressions, (4) lengthy "
jam band"-style improvisation. However, not all these elements are always present in progressive bluegrass.