Neither John Brown Sr. nor any of his four sons, John Brown Jr., Joseph, James or Newton, homesteaded any property in San Bernardino County.
In checking rootsweb.com and Bureau of Land Management records for all of the property supposedly owned by the Browns, it was discovered that much of the ranch was patented to the Southern Pacific Railroad in the 20th Century, including all of Section 15 and three-quarters of Section 23. This means that a good deal of the ranch was made up of possessory claims, grazing rights or something other than a full and complete title.
Also, there were other parcels which purportedly belonged to the ranch but were patented to various individuals, all in the 20th Century. In fact, the only property patented to the Browns, other than the original purchase by John Jr. and Joseph Thorn (480 acres), was 160 acres which the youngest brother Newton purchased in the 1880s.
How the Section 36 property was obtained is unknown, but it would have been administered by the state, and could not have been homesteaded. Sections 16 and 36 in each township were granted to California by the Congressional Act of March 3, 1853, the proceeds from which were to be used for public education.
This gives some significance to the statement in the McClure report that James "had 1,500 acres fenced." It was fenced but apparently not owned. The railroad patents were issued long after the Browns had lost the ranch, but the legal entanglements must have been a mess for their successors, which is another whole story in itself.