Fire Management

Prescribed burn on Waubay NWR. Photo by USFWS

Fire, whether set intentionally or caused by lightning, has been a part of prairie ecosystems for thousands of years. 


Fire provides one or more of the following benefits in grasslands:


  •   removes dead vegetation   
  •   releases nutrients to enrich the soil  
  •   sets back non-native invasive plants   
  •   encourages growth of native species   
  •   creates habitats attractive to wildlife     


Grasslands are burned primarily to increase biological productivity and diversity to accomplish specific goals. The goals may be broad (prairie restoration and maintenance) or narrow (management for endangered or rare species or reduction of woody plants). 

Where native prairie is not a major component of the grassland, nearly all prescribed fires are used to reduce old plant growth, to control weeds, or to improve the height and density of plants. This results in improved nesting cover for waterfowl, and some migratory and resident bird species. Where native prairie is a major part of a grassland, the primary reasons for burning are to restore, improve, or enhance prairie habitat for wildlife, particularly grassland birds and pollinators. Prescribed burning in native prairies helps to reduce exotic cool season grasses, shrubs or trees, and stimulates growth of native grasses and forbs (flowers).    

Timing of burns is important to achieving management goals.  Most prairies are invaded by non-native Kentucky bluegrass or smooth brome.  To reduce these species and allow more space and nutrients for native grasses and forbs, prescribed fires are planned for mid to late spring. Another way of affecting non-native grasses is to burn a site in the fall when all grasses are dormant and allow cows to graze the area in the spring just when the early non-native grasses are growing.  This slows down the growth of exotic grasses allowing native grasses to out compete them. 

There are many factors that complicate the use and results of prescribed burning.  First and foremost is being able to burn safely, making sure fires do not get out of control and damage other property or cause personal injuries.  The U.S. Fish & Wildlife Service requires all personnel that conduct prescribed fires are properly trained and in good physical condition.  A certain amount of people and equipment are needed to conduct burns safely and efficiently. Finally, all burns require a burn plan that outlines why we are conducting a burn, what we want to accomplish, and how we plan to carry out the burn.  An important component of the burn plan is weather conditions that take into account temperature, wind speed and direction, humidity level, and any expected changes while the burn is carried out.  If conditions are outside of the prescribed measures the fire will not be started or will be put out if the burn is already taking place.    

The results of a prescribed burn will depend on past management of a site which will influence the type of vegetation present and litter layer, weather conditions on the day of the burn, precipitation, the size of an area burned, and the landscape.  Ideally, a site will burn unevenly, leaving some patches green or lightly burned and others black and covered with ash.  This mosaic effect provides more habitat for insects and wildlife both during and after a fire. 

Patchy burn