The studio recordings featured on "(Untitled)" mostly consisted of newly written, self-penned material, including a number of songs that had been composed by McGuinn and Broadway theatre impresario Jacques Levy for a planned country rock musical titled "Gene Tryp" that the pair were developing. Plans for the musical had fallen through and as a result, McGuinn decided to record some of the material originally intended for the production with the Byrds. Among the "Gene Tryp" songs included on "(Untitled)" was "Chestnut Mare", which had originally been written for a scene in which the musical's eponymous hero attempts to catch and tame a wild horse. The song was issued as a single in the U.S. on October 23, 1970, but it only managed to climb to number 121 on the "Billboard" chart. Nonetheless, the song went on to become a staple of FM radio programming in America during the 1970s. "Chestnut Mare" did much better in the UK, however, when it was released as a single on January 1, 1971, reaching number 19 on the UK Singles Chart and giving the Byrds their first UK Top 20 hit since their cover of Bob Dylan's "All I Really Want to Do" had peaked at number 4 in September 1965.