The Agricultural Council of Nevada is seeking farms or ranches that have been in the family for 100 years or more. The Ag Council is the lead sponsor of Nevada's Centennial Ranch and Farm Awards Program. Forty-five Nevada families have been inducted into the program since it started in 2004. "Many of Nevada's Centennial award-winning ranches and farms date back to the 1860s," said Liz Warner, program coordinator. The oldest is the Cushman-Corkill Ranch in Churchill County. Other long-time ranches include the Snyder Livestock Co. in Mason Valley (1862), the Laura Springs Ranch in Carson Valley (1863), Stewart's Ninety-Six Ranch …