LANDFIRE's 2023 Update (LF 2023) Forest Canopy Height (CH) describes the average height of the top of the canopy for a stand. CH is used in the calculation of Forest Canopy Bulk Density (CBD) and Base Height (CBH). CH supplies information for fire behavior models, such as FARSITE (Finney 1998), that can determine the starting point of embers in the spotting model, wind reductions, and the volume of crown fuels. To create CH, LANDFIRE's Existing Vegetation Height (EVH) product must be produced first. EVH is a continuous scaled product which assigns height to all life forms in the LF data, this product is created using an image-based process (within the Conterminous United States (CONUS)) to assess canopy structure for areas disturbed in the past twenty years. CH is then derived from EVH by assigning bins of 13 height classes for fuel production and use in fire behavior software. In LF 2023, fuel products are created with LF 2016 Remap vegetation in areas that were un-disturbed in the last twenty years. To designate disturbed areas where CH is modified, the aggregated Annual Disturbance products from 2014 to 2023 in the LF Fuel Disturbance (FDist) product are used. All existing disturbances between 2014-2023 are represented in LF 2023, and the products are intended to be used in 2024 (the year of release).
When using any product from the LF 2023 fuel product suite, users should consider adjusting fuel layers for disturbances that occurred after the end of the 2023 fiscal year (after October 1st, 2023). Disturbances that occurred after the end of the 2023 fiscal year are not accounted for within LF 2023 fuel products. Learn more about LF 2023 at https://www.landfire.gov/data/lf2023.