This product ("Prairie fires") presents burned area boundaries for The Flint Hills Ecoregion (KS and OK), one of the most fire prone ecosystems in the United States where hundreds of thousands of acres burn annually as prescribed fire and wildfire. The prairie fire products provide the extent of larger prairie fires in the Flint Hills to record the occurrence of fire and can be used to identify individual burned areas within the perimeters. This product is published to provide fire information of the most fire prone ecosystems to individuals and land management communities for assessing burn extent and impacts on a time sensitive basis. The methods used to produce the prairie fire products from 2009 to present are different than Monitoring Trends in Burn Severity Program (MTBS) methods. The product is developed by running a classification tree model on Landsat and Sentinel imagery for all available image dates with visible fires and without greater than 80 percent cloud cover in the spring of each year. The model takes each image, uses all Landsat bands 2-7 or Sentinel 2b bands 2-4, 8, 11, and 12, and finds thresholds between burnt and unburnt areas to create perimeters. Fire perimeters are created by the model and no manual editing is performed. Thus, these data are 100 percent (model based) auto-generated, however, analysts do review and remove small polygons less than 3 acres. The Prairie Fire dataset will include multi-part polygons and have one record for each source image date. These new methods are optimized to efficiently map and characterize the large number of fires that occur in this region on an annual basis. Prior to 2009, the standard MTBS fire mapping methods were used. Because of the unique frequency and extent of fire in this prairie biome, these fire products are now delivered through the Burn Severity Portal and are no longer included as part of the MTBS products unless a fire is identified in IRWIN, NFPORS or a legacy federal fire occurrence database. The provided data products will vary slightly based on the mapping methodology applied at the time of fire occurrence (pre-2019 or 2019 and later). This map layer is a vector polygon shapefile of fires occurring three acres and greater in size between calendar year 1986 and 2024 for the Flint Hills Ecoregion.