If you have some land you would like to preserve for Agricultural or Open Space use, you might want to check out the Williamson Act:
Williamson Act - Agricultural & Open Space lands
The California Legislature passed the California Land Conservation Act - commonly referred to as the Williamson Act - in 1965 to preserve agricultural and open space lands by discouraging premature and unnecessary conversion to urban uses. The Act creates an arrangement whereby private landowners contract with counties and cities to voluntarily restrict land to agricultural and open-space uses. The California Department of Conservation has more details.
For property in Nevada County, applications for a Williamson Act contract are filed with the Nevada County Planning Department. Application forms and processing Guidelines are available on the Planning Department website.
You can also speak to a Planner by contacting the Community Development Agency at (530) 265-1222.
If you questions regarding valuation of your Nevada County property under a Williamson Act contract, please contact the Nevada County Assessor at (530) 265-1232.