Fig. 2

Spatial scale of lightning-generated and prescribed fires. In our literature review to determine how fire attributes were discussed, we found that, according to observations in the Federal Wildland Fire Occurrence (n = 9511), most lightning-generated fires that occurred between 1980 and 2016 in the US were less than 1 ha in size. In contrast, less than 20% of prescribed burns occurred at a spatial scale of less than 1 ha. The most massive lightning-generated fire (61 903 ha) was 55% larger than the most massive prescribed burn. However, prescribed burns accounted for most of the fires >5000 hectares. We transformed fire size by taking the logarithm of the hectare value by the base of the mathematical constant e (natural logarithm transformation). The axis tick labels are back-transformed to ease interpretation