The USGS Upper Midwest Environmental Sciences Center developed a Monarch Butterfly Relevant Land Cover data set covering the conterminous United States of America. This data set was used primarily to assist in forecasting the number of milkweed stems on the landscape. Milkweed are required by monarch butterflies for reproduction and one possible cause for the decline in monarch butterfly numbers is thought to be the loss of milkweed. We used the Cropland Data Layer 2015 as well as additional spatially explicit information to develop the monarch relevant land cover data set. Additional sources of information included 2014 United States Department of Agriculture Conservation Reserve Program enrollment locations; railroad,...