From the LIFE magazine article, Horse Roping in Nevada is a Picturesque Feat; 21 June 1937.
The story: "A swank Nevada dude ranch in Reno's Nevada Stock Farm which covers 300 acres and boasts the greatest number of Palomino (Spanish origin) horses in the world. Here you see Cowboy Jack Case, a touring rodeo contestant who specializes in bronco-busting and horse roping, lasso one of the ranch's horses prior to trimming its hoofs - an operation which is performed every six weeks. . . "