Grassland String Band’s origin story is refreshingly simple. At a bluegrass jam session on Athens’ Eastside in 2012, banjo player Jody Daniels was introduced to a young mandolin player and singer brimming with talent and energy.

“At the end of that evening, I asked him who he was and who he played with,” says Daniels. “And the answer was, ‘I’m Michael Lesousky, and I'm kind of new here.’ And [that] was the beginning of a friendship, and the birth of Grassland String Band.”

The bond between the twentysomething Lesousky and sexagenarian Daniels is as unconventional as Grassland String Band’s music, which uses acoustic traditionalism as its base but adds elements of pop, rock and gospel to create a composite sound that caters to old-school purists and music-fest millennials alike.

The group’s six members vary in terms of age, background and experience. Guitarist Kevin Fleming is classically trained, while Daniels learned banjo later in life. Fiddler Adam Poulin has honed his chops by gigging steadily with seemingly everyone in town. The band revolves around Lesousky, a singer-songwriter with a soulful wail, and the rhythm section of drummer Todd Ferguson and bassist Nathan Elder employs a jazz-like grasp of dynamics to round out the sound.

After releasing a 2014 full-length, Before the Feast, the group holed up in an Asheville, NC studio during a snowstorm to record a four-song EP, The Echo Mountain Sessions. The storm “[forced] the engineer and support staff to live in-studio for the weekend, only [adding] to the experience,” says Ferguson. The EP, recorded live in two days, radiates familial warmth, from poignant opener “American Flag” to single “Give Me a Reason,” slow jam “Diamond” and rollicking closer “Boom Boom.”

The Echo Mountain Sessions reflects Grassland’s continued evolution, as Lesousky’s probing folk tunes and Daniels’ spirited anthems have both become rounder and more inclusive.

“The style shift was just a natural progression into the deeper realms of the heart and mind,” says Lesousky. ”I’ve grown a lot personally [and] as a songwriter, and the band grew over the past three years… I think that allowed us to tread into territories that had more meaning and to be comfortable with leaving the trappings of bluegrass and the conventional songwriting devices.”

The group’s process is deliberate, Lesousky adds. “We tinker with [a song] until it's right. We usually don't settle on an arrangement for months. We make sure the feel of the song fits the story and emotion we want to evoke.”

Though this level of professionalism may be at odds with Athens’ prevailing punk ethos, Grassland String Band has amassed a sizable local fan base of folks who might not otherwise find themselves downtown on a Friday night. From the beginning, says Daniels, “we were all over the spectrum in terms of musical influences and in our ages, [and] that diversity seemed to widen our appeal. We could look out at an audience and see young and old and every manner of cultures.”

In addition to the new Grassland EP, Lesousky released a seven-track solo album earlier this month. Deep Shade of Blue is country-tinged, featuring only voice and guitar. In contrast to his band’s intensive creative approach, Lesousky’s solo record is nakedly direct. “These songs are expressly raw and immediate,” he says. “I recorded them [at] a demo session and decided that ‘good enough’ was good enough.”

Grassland String Band is busy in general, and extremely so this week. The band will play twice—an unofficial Wildwood Revival kickoff Thursday and an EP-release show Saturday—and Lesousky will celebrate Deep Shade of Blue Sunday with a performance at The World Famous. Look for each show to offer something a little different.

“The mystery is the fun part of it all,” says Lesousky. “We usually don't know exactly what we are gonna do until we are doing it. I like it that way.”