Sirch, M.W., D.S. Sullins, N.J. Parker, D.A. Haukos, J.D. Kraft, C.A. Hagen, and K.A. Fricke. 2022. Woody species mortality due to a megafire within the mixed-grass prairie. Prairie Naturalist 54:11-23. https://www.eaglehill.us/prna-pdfs-regular/prna-54/prna-008-Sirch.pdf
Lack of fire in contemporary grasslands has contributed to the invasion of woody plants that often survive low- to moderate-intensity fire upon maturity. Knowledge of the effect of megafires (>40,000 ha) on grassland tree mortality and role of megafires in maintaining large grasslands is limited. We first quantified severity and spatial extent of a megafire using remote sensing techniques and then evaluated the effect of the megafire on woody canopy cover and tree mortality within the mixed-grass prairie of Clark County, Kansas, USA. We also used remote sensing techniques to estimate woody cover change and performed ground surveys to estimate woody species mortality, top-kill rates of woody species, size of remaining woody vegetation, postfire herbaceous composition, and the influence of herbicide and wildfire interaction on non-native saltcedar (Tamarix ramosissima Ledeb.). The megafire killed 33 ± 2% of saltcedar and 18 ± 1% (mean ± SD) of all other trees, including all eastern redcedar (Juniperus virginiana L.), and another 54 ± 2% of trees were top-killed and resprouted. Herbicide treatments in the burned area before the fire did not reliably increase saltcedar mortality. We conclude that further postfire management may be required to limit woody encroachment following megafire.