"Roundup-Series III" is not illustrated in Joseph Traugott's catalog "Stony Silence" analyzing the prints of Frederick O'Hara, but is perhaps listed in the checklist in the back.
O'Hara learned the color woodcut technique from Adja Yunkers in Albuquerque, New Mexico, probably in 1949. He then went on to study lithography with Elmer Schooley who taught it at Highlands University in Las Vegas, NM.
O'Hara's printmaking was always pushing the edges of imagery and technique, always experimental. In this print he has enhanced the woodgrain of the background block and printed the resulting grainy texture in a couple of passes using different colors. On top of this he has created a herd of longhorn cattle and a cowboy and horse using small blocks, printed in blacks and browns.
The overall composition could well be a response to the 1948 Stan Jones western song "(Ghost) Riders in the Sky" the first two verses of which reads: An old cowboy went riding out / One dark and windy day / Upon a ridge he rested / As he went along his way / When all at once a mighty herd / Of red eyed cows he saw / Plowin' through the ragged skies / And up the cloudy draw