Description of Burn Severity Rankings LOW: The majority of the delineated area has not been significantly altered by the fire. Significant amount of organic layers remain intact or singed leaf litter and duff remain, ash is sparse, small unburned fuels remain, canopy is largely intact, and grass and shrub root crowns are intact. Areas where pre-fire vegetation was sparse, and/or bare soil and rock fragments dominate should be classified as Low severity since there was little fuel to burn to begin with. Low severity burn areas do not contribute to an emergency watershed condition, but they may act as buffer areas to mitigate flood hazards that originate on more severely burned areas. Over-story mortality is generally minimal but can be significant in some cases. MODERATE: This class is the most difficult to define, but think of it as intermediate between Low and High Its specific characteristics may vary depending on the ecosystem types involved in the fire area. Less than 40 percent...