Slow-moving fires can do more damage than those that move rapidly across a site. In forest settings, crown fires that travel from the crown of one tree to another often are more damaging than other types because they destroy the foliage and thus reduce the plants' capacity to photosynthesize. This inability to manufacture carbohydrates weakens the plant and makes it more susceptible to subsequent winter damage and pest infestations. Young trees are more severely affected by this type of fire than older trees. However, new tissue laid down in the following spring allows many damaged trees to survive.
Shrubs often survive by their ability to re-sprout from their bases.
Degradation of Site Quality Fires burn soil organic matter, reducing the soil's capacity to store water and fostering compaction. They accelerate erosion and increase the magnitude of fluctuations in soil temperatures. As much as 70 percent of the nitrogen and some other nutrients are lost by volatilization, ash convection, and subsequent leaching after hot fires. However, the nitrogen is often replaced quickly by rain, increased soil microbial activity, and nitrogen fixation. Some nutrients are also released from burned organic matter, often making the total availability of mineral nutrients to the plants higher after the fire than before.