Rangelands

The Forest Service is a steward of many of our nation's most treasured landscapes, and within those landscapes are resources that people need and want, such as clean air and water, recreational opportunities and forest products. Impacts from increasing climate variability, extreme weather, and other disturbances—along with changing human demands—challenge our ability to ensure that ecosystems are healthy, resilient, and thus more adaptable to changing conditions. The Office of Sustainability and Climate supports national forests and grasslands with the tools, training, and resources they need to build resiliency into their landscapes in the face of a changing climate.

Several datasets that can be found in the Raster Data Warehouse can be downloaded from the links below. Other datasets from OSC can be downloaded from the Research Data Archive.


Dataset:

Extent of coterminous U.S. rangelands
This raster dataset depicts rangelands in the coterminous U.S., including transitional rangelands and small patch-size rangelands. Each 30 meter pixel is assigned a land cover category, including Rangeland, Afforested Rangeland (experiencing encroachment by trees [> 25% tree cover]) and Transitional Rangeland (currently dominated by herbs or shrubs that will likely become forested without management intervention).

Rangeland is land primarily composed of grasses, forbs, or shrubs. This includes lands vegetated naturally or artificially to provide a plant cover managed like native vegetation and does not meet the definition of pasture. The area must be at least 1.0 acre in size and 120.0 feet wide.

Rangeland extent is an important factor for evaluating critical indicators of rangeland sustainability. Rangeland areal extent was determined for the coterminous United States in a geospatial framework by evaluating spatially explicit data from the Landscape Fire and Resource Management Planning Tools (LANDFIRE) project describing historic and current vegetative composition, average height, and average cover through the viewpoint of the Natural Resources Inventory (NRI) administered by the Natural Resources Conservation Service. Three types of rangelands were differentiated using the NRI definition encompassing rangelands, afforested rangelands, and transitory rangelands.


Rangeland Productivity:

This dataset describes annual productivity in the non-forest domain of the coterminous US. Production data were generated using the Normalized Difference Vegetation Index (NDVI) from the Thematic Mapper Suite from 1984 to 2018 at 250 m2 resolution. This includes the Thematic Mapper (TM; Landsat 5), Enhanced Thematic Mapper (ETM+; Landsat 7) and Operational Land Imager (OLI; Landsat 8). The NDVI is converted to production estimates using two regression formulas depending on the level of the NDVI; there is one equation for lower values (and thus lower production values) and one for higher values. This dataset yields estimates of annual production of rangeland vegetation in pounds per acre and should be useful for understanding trends and variability in forage resources anywhere rangelands are common. There is an individual raster for each year included in the study (1984 – 2018). Separate data are available for the productivity as well as the Z-scores, which allow for easier comparison of annual relative productivity in coterminous U.S. rangelands, and for rapid display in online time-enabled applications.