Fig. 4
From: Not just crop or forest: an integrated land cover map for agricultural and natural areas
Percentage of county area with reference data for the conterminous United States. For 2017 CDL, reference data were from a USDA administrative crop database and National Land Cover Dataset imagery. For NVC, reference data were field plots in LANDFIRE reference database, with a minimum of 30 field plots per NVC class. For SPAN, we calculated coverage of reference data as a fraction of agricultural and unmanaged classes, respectively, while, for the merged product, coverage of reference data included agricultural and unmanaged classes. To facilitate mapping, we converted values to discrete intervals using Jenks natural breaks.
