Thought I would join in just for the fun of it.
The term that comes to mind is "deeded acres". Our initial ranch consisted of 7,000 "deeded acres" all irrigated, and was supplemented by all of the integrated school and railroad sections that bordered the deeded acres which we leased from the government.
I realize that is not a mega-ranch by any stretch. But the method by which it was built was pretty standard.
The deeded acres were acquired during the depression. My grandfather, a ranch hand working for between $10-35 a month, never believed in banks and so saved his cash. My grandmother saved all of her salary as a school teacher - grandpa was determined to support his wife, so her money was not touched for living expense. When area ranches were lost and the cost of land went down after the crash, cash was king at the time, and he was able to buy the 7,000 acres at a dollar an acre.
He managed the ranch to become self-sustaining. He never borrowed money from a bank. He did not believe in "operating" lines of credit, a mortgage on the land was a sacrilege. He just saved and spent wisely, and over the years built a beautiful operation. His position was that regardless of the economic situation, our ranch would not be threatened by foreclosure, and his family would have a home that would sustain it.
We did border a couple of mega-ranches - and when visiting home last year I learned that those outfits have continued to grow. One was financed (and later fertilized) by a garbage hauling business in Denver, the profits from which were used to buy up land during the depression. The other was built by a "remittance man". There were several in early Colorado history -- an English Lord whose family back home paid him to stay away -- evidently they had committed some act that threatened the family's good name. Some continued the "rogue" behavior and lost their shirts in ranching -- others grew up so to speak and succeeded.
The point being that most mega-ranches were actually purchased initially by people with money from another businesses following a dive in the price of land. Some of those ranches were purchased solely to provide "tax deductions" for the other business. I remember one wealthy rancher glorying in his poor calf crop -- saying nothing creates tax deductions like a ranch. He was a state senator and also owned a meat packing business.
Anyway, often, the "deeded" land was augmented by leases of adjoining federal and state lands for pasture. When the government sold that land, which it sometimes did, area ranches bought it, and continue that practice today. Many of the ranches also relied on cash flow from the other business -- some were managed successfully, some not.
[This message has been edited by Connie Muggli (4/4/2012)]