Fire in Ecosystems: Forests

Trees found in forests may be overwhelmingly similar or varied depending on location and other factors.

NPS

Forests cover a wide range of environments, from tropical to temperate to boreal. There may be one or two tree species in a forested system to dozens of tree species. A lot depends on the environmental and soil conditions, and/or natural disturbances, such as fire, insect outbreaks, and blowdown. In many forest systems, time between fires, their intensity, and season in which they burn, influence tree species that grow and their arrangement on the landscape.

In some forested areas, fires burn fairly often, and and at low intensity. The fires in these areas usually thin out and reduce the number of small trees and burn dead and down material on the ground in the forest, while the larger trees survive. Areas that once burned often, but later had fires suppressed or excluded, require active management to restore and maintain their health.

In other forested areas, fires occurred much less frequently and are often higher severity when they did occur, for example in lodgepole pine forests. The fires in these areas generally affect all trees in an area and change the system. It takes a number of years for the forest to grow back. Areas like these are altered less by past fire suppression, but are at risk of change due to changing climate conditions, allowing fires to burn more frequently than in the past.

The National Park Service studies forests to understand forest health. We use the information to develop plans to manage fires in each forest system. The goal is to restore and maintain a sustainable forest for the future where possible.