"Words to "A Roundup Lullaby" (correctly given above but no 'e' on lullaby) were published by Charles Badger Clark in 1915 in his "Sun and Saddle Leather," a thin volume of 56 pages. The volume was re-issued in 1917, illustrated with photographs by the famous Montanan, L. A. Huffman, at one time post photographer for General Miles at Ft. Keogh. Several other editions followed, with new poems added in 1919. The collected edition, with "Grass Grown Trails," and additional poems, came out in 1920.
Clark was raised in the Deadwood area, South Dakota. He went to Cuba with a colonizing effort after the "Spanish War" and later worked on a plantation. He was jailed in connection with a shooting but was later acquited. On his return, he briefly edited a paper in Lead, S. Dak., then went to Arizona, where for four years he was in charge of a small ranch near the Mexican border. He returned to South Dakota. (From preface by 'R. H.' in a Chapman and Grimes edition.

"A Roundup Lullaby" has been set to several tunes.

By Clifton W. Barnes, mentioned above. Not Found. Does anyone know where to find a copy? Date?

By Estelle Philleo, 1919, sheet music pub. by M. St. Vrain Sanford, NY, reprinted 1920. Full copies can be seen in the University of Colorado Digital Sheet Music Collection (Link below).

By Gertrude Ross, 1922, sheet music published by White-Smith Music Pub. Co., Boston. Full copy in Univ. Colorado Collection (Link below)

Unknown. Bob Nolan, Sons of Pioneers, was suggested by Katie Lee. Music p. 219, Katie Lee, 1976, "Ten Thousand Goddam Cattle," Northland Press.
Colorado Sheet Music: http://uclibraries.colorado.edu/cgi-bin/sheetmusic.pl?WesternTrails&titlepages&5
Sheet Music