"Sam Bush is a Bluegrass institution."

A true statement, but possibly a misleading one. Institutions are stodgy and tradition-bound, and even though Bush--who's headlining this Sunday's show at Beartrap Summer Festival--recently embarked on his sixth decade of life, nobody has ever accused him of being either.

It's true there was an official and somber moment a while back, when the Kentucky General Assembly convened inBowling Greenand approved a bill naming Bush (who wore an unaccustomed necktie) "The Father of NewGrass Music." He told those assembled, "For a kid who was raised on a farm out onMorgantown Road, this is very humbling. I'm very proud of where I'm from."

But afterward, he livened up the occasion with a wisecrack: "If Bill Monroe is the Father of Bluegrass, I could be the Mother of Bluegrass. Because if Bill were here and saw me, he'd say, 'Here comes that mother now!'"

Bush is also credited with coining the term "NewGrass," and one of his early bands was named, not surprisingly, The NewGrass Revival. NewGrass (which Wiki prefers to disambiguate as "progressiveBluegrass") is defined as "using electric instruments and importing songs from other genres, especially rock and roll," and "incorporating non-traditional chord progressions and lengthy jam band-style improvisations.

Hearing Bush perform, a listener might add jazz, reggae, and world music to those crossover categories, even if the blend is sometimes subtle. It's tempting to think that his ancient Gibson mandolin is the source of his magic. Until you see him pick up the nearest fiddle at hand and set off on a staid, traditional string tune only to suddenly branch into chords and tempos that would keep a good modern jazz group on their toes providing accompaniment.

The young Sam Bush came to country andBluegrassvia his father Charlie's comprehensive record collection, and by watching the Flatt and Scruggs TV show. He got his first mandolin at age 11, and soon added a fiddle. As a teenager, he won first place three times in the junior division of the National Old-Time Fiddler's Contest in Weiser, ID.

Much more recently, the International Bluegrass Music Association (IBMA) named him Mandolin Player of the Year four times, and called on him to host the 22nd annual event at the Grand Ol' Opry House inNashville. The Americana Music Association (AMA) presented him its Lifetime Achievement for Instrumentalist Award at the Ryman Auditorium in 2009.

Oh, and add three Grammys to that: Best Country Performance by a Duo or Group with Vocal (Emmylou Harris & the Nash Ramblers, eponymous album, in 1992), Best Pop Instrumental Performance (Bela Fleck & the Flecktones, "Sinister Minister," 1996), and Album of the Year, with various artists on "O Brother, Where Art Thou" in 2001. He was nominated for a fourth: Best Country Instrumental Performance, with Jerry Douglas and Bela Fleck on "Who's Your Uncle?" (2006).

Bush has long been considered a main attraction at the legendary Telluride Music Festival in Telluride, Colorado, where he plays the Saturday, 8 pm set each year as well as guest performances throughout the weekend. The number of virtuoso musicians that Bush has performed and collaborated with, there and elsewhere, would form a list that taxed Internet bandwidth, but just a few are: Doc Watson, Linda Ronstadt, Dolly Parton, Tony Rice, Peter Rowan, David Grisman, and Mark O'Connor.

The Telluride sessions have resulted in a new band for Bush. He plays with Rice, O'Connor, Bela Fleck, Edgar Meyer, and Jerry Douglas in a group known as "Strength in Numbers."

But despite his list of accomplishments, Bush remains characteristically self-effacing. As he told a reporter on the release of his 2009 album "Circles Around Me," “I tend to rejuvenate every so often. I do different projects and move in different circles. I started out in high school playing my mandolin and being progressive that way, and I do feel comfortable as a singer and player. I’ve dabbled in reggae, South African, jazz, rock, and I played with Jean-Luc Ponty on a record.

"But with this album, I feel like I'm just now starting to get somewhere."