Because fire is a natural component of Northern Great Plains grassland ecosystems, prairie vegetation is very well adapted to recover following a fire. Unfortunately, several of the conditions that can make fire a beneficial management tool with prescribed burning are absent in many wildfires. A fire prescription or burn plan designed to reduced one species or group and encourage another would include specific conditions such as a target fuel load, favorable growing conditions, good moisture and acceptable wind speed, wind direction and relative humidity. These conditions most often exist early in the growing season. If prescribed conditions are not met, the burn is not conducted. In contrast, wildfires occur when conditions may be very unfavorable.

Wildfire impacts both components of the soil-plant complex. Under optimum conditions, the soil surface is protected by a layer of litter, old plant material undergoing the decay process. This litter layer along with standing vegetation reduce evaporation and serve to protect the surface from soil movement caused by wind or rain. In addition, litter promotes the infiltration of rainwater, reducing runoff and enhancing soil moisture. During winter, standing vegetation is important for snow capture, which contributes to later soil moisture.

Wildfires also remove whatever live plant tissue was present at the time of the burn. As plants initiate new growth following the fire to reestablish photosynthetic leaf tissue, they will draw down stored reserves in the same manner that occurs with new growth in the spring. If reserves have not been replenished by the time autumn freezes occur, the plant’s reserve status will be compromised and spring recovery may be less vigorous.

Although the landscape may appear devastated following a fire, grassland species are adapted to fire, they will recover. In contrast to woodland fires where fuel loads may lead to extended periods of very hot temperatures, grassland fires generally move over individual plants very rapidly, minimizing the duration and intensity of elevated temperatures. The rate of post-fire recovery is controlled primarily by the condition of the vegetation before the fire and moisture conditions following the burn. Healthy, vigorous rangeland will recover rapidly following a fire, just as it does after a drought. The rate of recovery of rangeland vegetation stressed by long term overgrazing will be much slower.

When favorable growing conditions return, the first plants to respond will be annual broadleaves. These weedy species are nature’s mechanism to protect the soil surface as rapidly as possible. While this flush of growth is normally transient and will be replaced by perennial plants, land managers must be alert to the invasion of troublesome weeds during the early stages of post-fire recovery. Early treatment of small plants or patches will be much more effective than later treatment of well established weeds.

Best management for rangeland following a burn is rest from grazing. Unfortunately, regrowth following a burn is both palatable and nutritious. Precaution will have to be taken to ensure that livestock are excluded from burned areas for as long as possible. For example, if only a portion of a pasture has burned, a temporary fence to exclude grazing should be established.

The greatest benefit for vegetation following a fire will be a complete growing season rest, perhaps grazing again after vegetation is dormant in the fall. If an area must be grazed, delaying at least until important plants have reached maturity and set seed will be beneficial. Productivity of plants surviving after a fire will be reduced. Stocking rates will need to be adjusted downward, perhaps as much as 50% when grazing is resumed.

While there is a strong desire to “do something” following a fire, there is no evidence that tillage or other soil treatments or reseeding will be of any benefit. Some research indicates they can be detrimental. Management following a fire boils down to reducing matching animal demand and feed supply by reducing animal numbers and/or identifying alternative sources of feed. Delaying a return to grazing on burned areas will benefit the vegetation and restore its productivity.