From Los Angeles, Nelson moved to Berkeley and worked at Discount Records while she looked for musicians who could fit her repertoire of blues, R&B and gospel, declining an invitation to audition for the Jefferson Airplane (singer Signe Anderson was retiring). Nelson was looking for an environment that would showcase her musical preferences, and she decided that the Airplane’s psychedelic acid rock wasn’t that environment. She found it in the form of a group of expatriate Texans.
Between 1965 and 1968, the Haight-Ashbury and the East Bay attracted a number of Texans fleeing law enforcement agencies (Doug Sahm and the Sir Douglas Quintet, for example) or the repressive, red-neck culture at home whose musical skills and interests were similar to Nelson's. They included Janis Joplin, Steve Miller, Boz Scaggs, members of Austin's Thirteenth Floor Elevators and Travis Rivers, publisher of The San Francisco Oracle, who is generally credited with discovering' Janis Joplin and bringing her to San Francisco. Impressed with Nelson's singing, Rivers became her manager, and matched her up with musicians from Texas and elsewhere to form Mother Earth, naming the band after the Memphis Slim song Tracy sang at his funeral in 1988.
While Rivers may have been looking for another Janis, Tracy sang with more delicacy than Joplin and drew her material from various genres, blues, R&B, psychedelic, gospel and pop ballads, which the band mixed with Texas-influenced sounds and phrases. By late 1966 Mother Earth was gigging regularly at the Auditorium, opening for the likes of the Grateful Dead, Jefferson Airplane, Big Brother & The Holding Company, Jimi Hendrix, and Eric Burdon. Their live show was, reputedly, quite a spectacle - Tracy barefoot in a long velvet gown singing most of the lead numbers while Powell St. John sang the others, usually wearing protective headgear made for airport workers. An appearance on the soundtrack to the 1968 movie Revolution (which also featured Quicksilver Messenger Service and the Steve Miller Band) led to a recording contract with Mercury Records, a relative latecomer to the San Francisco music scene.
The line-up that went into the studio included: Tracy on piano and vocals; Powell on vocals and harp; guitarist John Toad Andrews and Bob Arthur on bass, two Texans who'd come off a lengthy road tour with Margie Hendrix, one of Ray Charles' Raelettes: Texan drummer George Rains (who went on to tour and record with Boz Scaggs and Doug Sahm); arranger and keyboardist Mark Naftalin (from Minnesota via Chicago’s Butterfield Blues Band); a Texas horn section, including Bay Area great Martin Fierro and Link Davis, Jr. (whose father wrote the Cajun classic Big Mamou) and a group of background singers called the Earthettes (including Tracy herself under the name Shalimar Samuelson)