Sagebrush can be scarce after fires in a semiarid ecosystem and their paucity over vast burn areas creates challenges for detection by remote sensing.
USGS researchers considered how a vegetation model based on Landsat satellite imagery known as the National Land Cover Database (NLCD) compared with field-based vegetation measurements. They measured eight previously burned areas across the Great Basin to assess recovery of big sagebrush. Estimates of sagebrush cover from the NLCD were on average 6.5 percent greater than field-based estimates, a considerable difference given that maximum cover values of sagebrush were roughly 35 percent in the field. The NLCD detected consistent, reliable signs of sagebrush recovery after four to six years, contrasting with previous field-based studies that observed fluctuations over longer time periods. Results showed that Landsat satellite imagery can detect the influence of burns on shrub recovery, though authors note that further improvement of post-fire remote sensing products is warranted.
Applestein, C.V., Germino, M.J., 2021, Detecting shrub recovery in sagebrush steppe: comparing Landsat-derived maps with field data on historical wildfires: Fire Ecology, v. 17, no. 5, https://doi.org/10.1186/s42408-021-00091-7