| Table: Fire Severity Classification System |
| | Low fire severity | Moderate fire severity | High fire severity |
| Description | low soil heating or light ground char | moderate soil heating or moderate ground char | high soil heating or deep ground char |
| Litter | scorched, charred, or consumed | consumed | consumed |
| Duff | left largely intact, may be charred | deeply charred or consumed, light colored ash present | completely consumed |
| Mineral soil | not visibly altered | not visibly altered | top of mineral soil is reddish or orange on severely burned sites; below 1 cm, soil can be charred to a depth of 10 cm or more; surface soil texture altered, "fusions evidenced by clinkers" |
| Woody debris | partially consumed or charred | mostly consumed except for logs, which are deeply charred | logs are consumed or deeply charred |
| Soil temperatures at 1 cm | < 50o C | 100-200o C | >250o C |
| Depth of lethal temperatures for soil organisms | 1 cm | 3 to 5 cm. | 9 to 16 cm |
