The division of the Potrero de San Luis Obispo into farmsteads represents the pattern and boundaries of Cal Poly land acquisition.

1. The Serrano Ranch was owned by Miguel Serrano, the son-in-law of Estevan Quintana. He and his son farmed and grazed cattle until 1919 when they sold and leased portions of ranch. Victor Bello purchased the ranch in 1925, and eventually sold it to Walter Wells in 1944. Wells held onto the land as a benevolent act until 1950 when Cal Poly was in a position to purchase it. The ranch continues to be used for rangeland and grazing as it had since the beginning.

2. The Peterson Ranch, owned by Millard and Silvia Peterson, ran cattle and horses, thus continuing many of the same land use practices as the original Potrero and the neighboring Serrano Ranch. In 1950, Cal Poly purchased the ranch after years of pressure due to a need for more quality grazing land and its recent purchase of the adjoining Wells Ranch.

3. The Cheda Ranch, owned by John Cheda and his family, was originally developed for dairying. Cal Poly acquired it in a condemnation suit in 1952 to expand its outgrown campus dairy.