Three core members — lead guitarist Joe Ginet, keyboard player Erik Vestnys and bassist Ryan Redding — make up State of Jefferson.
Sidemen such as trumpet player Mikey Stevens and drummer Michael St. John join the band at various gigs.
The Grants Pass-based band, along with Ras Cricket and The Cultivators, will perform at 9 p.m. Friday, May 17, at Club 66, 1951 Ashland St., Ashland. The cover is $5.
"We're an Americana jam band, but there's overtones of reggae and world music rhythms in there too," Vestnys says.
State of Jefferson organizes two of Southern Oregon's largest outdoor music festivals: The Jefferson State Music Festival, tentatively set for June 29, and the Jefferson State Hemp Expo, set for Aug. 23-25, both in Grants Pass.
The band also collaborates with singers and songwriters from around the world for its series of sampler recordings.
"They lay down their guitar and vocal tracks, and we take it from there and engineer around it," Vestnys says. "These are compilation CDs with music by the State of Jefferson and songs by different composers."