Rancho Omochumnes (also called "Rancho Río de los Cosumnes al Norte") was a 18,662-acre (75.52 km2) Mexican land grant in what is now Sacramento County, California, given in 1844 by Governor Manuel Micheltorena to Jared Dixon Sheldon. The grant extended about seventeen miles along the north bank of the Cosumnes River opposite Rancho Cosumnes, and encompassed present day Elk Grove and Sheldon, south of Sacramento.
Jared Dixon (Joaquín) Sheldon (1813–1851) was born in Vermont and came to California in 1839. He spent one season in sea-otter hunting, and then worked building a house in Monterey. He formed a partnership with William Daylor (1810–1850). In 1844, Sheldon built a flour mill at the Russian settlement of Fort Ross and another mill in San Jose. Sheldon was granted the five square league Rancho Omochumnes in 1844. He did some building work for John Marsh and obtained three hundred head of cattle in exchange. In 1845 Sheldon permanently settled on his ranch, which had been attended to by William Daylor. Originally was known as the Sheldon Grant, the rancho was divided into Sheldon's Ranch, and Daylor's Ranch. In 1846 Sheldon’s flour-mill on the Cosumnes was in operation. In 1847, Sheldon married Catherine Rhoads (1832–1905) and Daylor married her sister, Sarah Rhoads (1830–1898). William Daylor died of cholera in 1850. In 1851 Sheldon erected a dam near Clark’s Bar for the irrigation of his lands. He was shot July 11, 1851 in a quarrel over a dam he had built that flooded miners' claims.
With the cession of California to the United States following the Mexican-American War, the 1848 Treaty of Guadalupe Hidalgo provided that the land grants would be honored. As required by the Land Act of 1851, a claim for Rancho Omochumnes was filed with the Public Land Commission in 1852, and the grant was patented to his widow, Catherine Rhoads Sheldon and the administrator of the estate, Gabriel W. Gunn in 1870.
In 1852 Catherine married John T.R. Mahone, who had been a soldier in the Mexican-American War. In 1872, Catherine married Dennis Dalton (1846–1908), a young Irishman who came to California in 1869. They settled on Rancho Omochumnes, where Catherine remained (almost) until her death in 1905.
Historic sites of the Rancho
- Site of Grist Mill. Grist mill built by Jared Dixon Sheldon in 1846.
- Ogden Hoffman, 1862, Reports of Land Cases Determined in the United States District Court for the Northern District of California, Numa Hubert, San Francisco
- Diseño del Rancho Omochumnes
- Winfield J. Davis, 1890, An Illustrated History of Sacramento County, California,. Pages 588-590. Lewis Publishing Company
- United States. District Court (California : Northern District) Land Case 182 ND
- Report of the Surveyor General 1844 - 1886
- Gunn v Bates, 1855,Reports of cases determined in the Supreme Court of the state of California, Volume 6, Bancroft-Whitney Company
- "Catherine Foster Rhoads Dalton". Find a Grave. Retrieved October 18, 2010.
- Site Of Grist Mill Built By Jared Dixon Sheldon (No. 439)