Open-range grazing

In the Western United States and Canada, open range is rangeland where cattle roam freely regardless of land ownership. Where there are "open range" laws, those wanting to keep animals off their property must erect a fence to keep animals out; this applies to public roads as well. Land in open range that is designated as part of a "herd district" reverses liabilities, requiring an animal's owner to fence it in or otherwise keep it on the person's own property. Most eastern states and jurisdictions in Canada require owners to fence in or herd their livestock.

The Western open-range tradition originated from the early practice of unregulated grazing in newly acquired western territories, which was codified in the laws of Western US states as they developed written statutes. Over time, as the Western lands became more developed (railroads, mining, farming, etc.) the open range laws started to be challenged and were significantly curtailed, but they still exist in certain areas of most western states. Open range conditions also existed in Western Canada prior to amendments the Dominion Lands Act in 1889 which prohibited cattle from grazing on unleased land, though the practice did not disappear immediately. Open range management has also been practiced in other areas, such as Caribbean and even the eastern state of South Carolina during the colonial period.

The practice was used in Mexico, and some argue it may have been the predecessor to the open range practice in the American West, which borrowed many other cattle raising techniques from Mexico.

Unlike the eastern United States, the western prairies of the 19th century were vast, undeveloped, and uncultivated, with scarce, widely separated sources of water. Until the invention of barbed wire in the 1870s, it was more practical to fence the livestock out of developed land, rather than to fence it in. As the United States government acquired western territories, land not yet placed into private ownership was publicly owned and freely available for grazing cattle, though conflicting land claims and periodic warfare with Native Americans of the Great Plains placed some practical limits on grazing areas at various times.

...
Wikipedia