This layer is geographically based on Bureau of Land Management (BLM) and U.S. General Land Office Geographic Coordinate Data Base (GCDB) 1:24,000-scale Land survey Information System Data Base (LSIS) data for the states of Nevada and Utah sourced from the U.S. Geological Survey (USGS) Digital Line Graph (DLG) dataset. Tabular data is derived from the Nevada Division of Water Resources (NDWR) Crop Inventory Data. NDWR inventories irrigated acreage for Newark and Steptoe Valleys on an annual basis. Estimates of irrigated acreage are developed from observations made during field work performed primarily during the August through December time period and are reported annually in a series of crop inventories. The Newark Valley inventory includes irrigation in the northern part of Little Smoky Valley. NDWR crop inventories identify and define irrigated acreage by township, range, section, quarter section, and quarter-quarter section. Only NDWR crop inventories for 2000, 2002, and 2005 are stored in the geodatabase.