Summary

Description

The National Land Cover Database (NLCD) Percent Tree Canopy Collection is a product of the U.S. Forest Service (USFS), and is produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC) Consortium (www.mrlc.gov). The MRLC Consortium is a partnership of Federal agencies, consisting of the U.S. Geological Survey, the National Oceanic and Atmospheric Administration, the U.S. Environmental Protection Agency, the U.S. Department of Agriculture (USDA) National Agricultural Statistics Service, the U.S. Forest Service, the National Park Service, the U.S. Fish and Wildlife Service, the Bureau of Land Management, NASA, and the U.S. Army Corps of Engineers. A primary goal of the MRLC Consortium is to generate current, consistent, and seamless national datasets of land cover, percent developed imperviousness, and percent tree canopy. NLCD 2001 Percent Tree Canopy was developed in three key steps: 1. Reference data of tree canopy density was derived from the high spatial resolution images. 2. Density prediction models were calibrated using reference data and Landsat spectral bands. 3. The models developed in step 2 were extrapolated spatially to map per-pixel tree canopy density. This method is described in detail in Huang et al. (2001). NLCD 2011 Percent Tree Canopy – Cartographic is the cartographic version of the NLCD 2011 Percent Tree Canopy – Analytical dataset for the 48 conterminous states. It was produced by the USDA Forest Service Remote Sensing Applications Center (RSAC). Tree canopy values range from 0 to 100 percent. The analytic tree canopy layer was produced using a Random Forests™ regression algorithm. The cartographic product is a filtered version of the regression algorithm output. Questions about the NLCD Percent Tree Canopy Collection can be directed to the NLCD land cover mapping team at USGS EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov.