"Bob was the singing voice for Ken Maynard in the 1934 film, In Old Santa Fe and appeared in at least 88 low-budget Western films, first for Columbia Pictures and later with cowboy stars Gene Autry and Roy Rogers. With the Sons of the Pioneers, he made guest appearances in high-budget A-movies like Hollywood Canteen, with Bing Crosby in Rhythm on the Range and in the Walt Disney short, Melody Time."
Wiki also says that Tumbling Tumbleweeds was a song that Nolan reworked from an earlier song he had written that was not a "western" song:
"Tumbling Tumbleweeds" is a song composed by Bob Nolan, one of the founding (albeit reluctant) members of the Sons of the Pioneers. Although one of the most famous songs associated with cowboys, the song was composed by Nolan back in the 1930s while he was working as a caddy and living in Los Angeles. Originally titled "Tumbling Tumble Leaves", the song was reworked into the title "Tumbling Tumbleweeds" and into fame with the Gene Autry film of the same name.