Evaluating an attempt to restore summer fire in the Northern Great Plains

Authors: McGranahan, Devan; Angerer, Jay

Submitted to: Environmental Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/30/2025
Publication Date: 6/13/2025
Citation: McGranahan, D.A., Angerer, J.P. 2025. Evaluating an attempt to restore summer fire in the Northern Great Plains. Environmental Management. 75:1656-1664. https://doi.org/10.1007/s00267-025-02209-y.
DOI: https://doi.org/10.1007/s00267-025-02209-y

Interpretive Summary: Prescribed fire managers often talk about burning in different seasons. Although there is information about fire effects in different seasons, little research has specifically addressed the opportunities for successfully burning in different seasons and under different conditions. We used historical data to compare successful and unsuccessful summer burn seasons in central North Dakota. Although grassland fuels in the summer were always more green than in the spring, summer burns could still be as severe as spring burns. Unsuccessful burn seasons were characterized by very green fuel and above average seasonal rainfall. An historical analysis did not indicate substantial changes in the fire environment at this specific location over the last 40 years. Slight increases in spring fuelbed greenness and slight decreases in spring relative humidity could likely counteract each other in terms of prescribed fire management.

Technical Abstract: There is growing interest in diversifying human-managed fire regimes. In many North American grasslands, late growing season burns re-introduce fire to periods most prone to lightning-driven fire prior to wildfire suppression policies. We report here on restoring summer fire in central North Dakota, USA, from a research project in which summer fire was only successfully achieved in two out of four years. We use remotely sensed imagery and local weather data to assess whether fuel or weather conditions limited burning in the summer, and to compare fire environmental conditions and subsequent burn severity across prescribed burns conducted in the spring and summer. Finally, we review historical data to determine if conditions have changed in either the spring or summer burn seasons over 42 years. We found that burn severity declined with fuelbed greenness but was independent of burn season—summer burns could effect as high of severity as spring burns despite having greener fuelbeds. What little phenological change seems to have occurred at the study location—slightly greener fuelbeds and slightly lower relative humidity in spring—likely offset each other to some degree. Overall, we found little evidence that successful summer burns were anomalies, and conclude that it is reasonable for managers to incorporate late growing season fire into prescribed fire programs with the caveat that some summers will simply be too wet and/or too green to burn.