As part of the next generation NLCD 2019 mapping process, the NLCD research team developed a suite of intermediate products that were used to generate the final NLCD Land Cover products. Some of those products also have value as independent products and are provided here. Please read the product descriptions to understand what the product represents.
This product shows the most recent forest disturbance date between the years 1986-2019 for every 2-3 year interval. This product combines information from the NLCD 2019 change detection, land cover classification, and the LANDFIRE Vegetation Change Tracker (VCT) disturbance product from 1984-2010. For NLCD 2019, this product was used to assess where disturbance occurred for forest areas. This product was originally intended only for forest areas, but it also can be useful for other landcover classes. For example, agricultural areas are typically disturbed yearly by tillage are represented as being disturbed prior to 1986. This "prior to 86" disturbance call was used in some instances as a delineation between forested and non-forest areas. Other classes that are not forest may also be represented with a disturbance indication if the area was forest at some time point during 1986-2019.
NLCD Forest Disturbance Date
This product was derived using the 8-epoch NLCD land cover (2001, 2003, 2006, 2008, 2011, 2013, 2016, 2019) from the released NLCD 2019 product suite. Any change between two consecutive epochs is calculated and the total change frequency/time for each pixel is recorded. This product shows an integer count total of any recorded change for the time period 2001-2019. This product is meant to be used with the change index and individual dates of Land Cover to provide users with a more in depth look at where multiple change events in the same location are occurring on the landscape.
NLCD Land Cover Change Count
To better develop NLCD 2019 landcover, spectrally stable grass and shrub areas were separated from the spectrally changing areas of shrub and grass represented by forest harvest, burns, regrowth, and other disturbances. Essentially, this separation usually identifies shrub and grass climax areas from shrub and grass areas in transition back to a forest. This difference is expressed with two extra classes of land cover, called Shrub-Forest and Herbaceous-Forest which are representing areas of current shrub and grass expected to transition back to a forest. Alternatively, the shrub and grass classes of Shrub/Scrub and Grassland/Herbaceous will likely not transition to a forest. However, be cautioned that no extensive ecological analysis went into these class delineations, they are primarily spectral based separations used to delineate broad classes of grass and shrub. The change index associated with this and the regular NLCD classes are identical.
NLCD Land Cover with additional Forest Transition Classes All Years
NLCD Land Cover with additional Forest Transition Classes Change Index
NLCD 2019 Land Cover with additional Forest Transition Classes
NLCD 2016 Land Cover with additional Forest Transition Classes
NLCD 2013 Land Cover with additional Forest Transition Classes
NLCD 2011 Land Cover with additional Forest Transition Classes
NLCD 2008 Land Cover with additional Forest Transition Classes
NLCD 2006 Land Cover with additional Forest Transition Classes
NLCD 2004 Land Cover with additional Forest Transition Classes
NLCD 2001 Land Cover with additional Forest Transition Classes