The USGS has been at the core of land cover and land use research and applications since the late 1960's. Under the geography banner within the survey, it is arguably the largest operational land cover agency in the world today. Land cover has historically been part of USGS's research heritage, and has been significantly influential in the science of mapping
land cover and land use.
Current mapping techniques of land cover would not be possible today without milestones such as James Anderson's 1976
publication entitled A Land Cover Classification System for Use with Remote Sensor Data. Anderson et al., produced three hierarchical levels of classifying land cover and land use with level three being the most detailed, representing over 100 landuse types. Development of such techniques has facilitated the mapping, modeling and measurement of many land cover applications, which in turn has
stimulated collaborative partnerships with other outside agencies.