Tallgrass prairie may respond differently to prescribed burning and subsequent preferential grazing, termed pyric herbivory, under variable climate conditions. This 6-yr study (2011−2016) compared tallgrass prairie pastures that were subjected to burned and unburned conditions while exposed to grazing under differing climate conditions in the Southern Great Plains of the United States. The study area consisted of six pastures, three burned and three unburned. Each burned pasture was further divided into three patches and subjected to a 3-yr rotational burning cycle. The Enhanced Vegetation Index (EVI) derived from Landsat 7/8 (EVI<inf>LS</inf>) and Moderate Resolution Imaging Spectroradiometer (MODIS, EVI<inf>MOD</inf>) was used to indicate vegetation production depending on size of pastures. On the basis of EVI<inf>LS</inf>, most burned patches (11 of 18) had lesser production (overall difference of 3%) than unburned patches within the same pasture. The differences were larger (13%) in a drought yr (2011) compared with normal (3% in 2013) and wet (<1% in 2015) yrs. The distribution of precipitation controlled EVI<inf>LS</inf> for periods during and after grazing. The burned patches tended to have lower EVI<inf>LS</inf> during grazing periods than the unburned patches within the same pasture, probably because of selective grazing of newly grown grass in recently burned patches. In contrast, the differences in EVI<inf>LS</inf> between during and after grazing periods were mostly (78%) smaller in burned than unburned patches. However, more variations in EVI<inf>LS</inf> existed among pasture comparisons due to landscape heterogeneity. Similar results were observed with EVI<inf>MOD</inf>. Overall, results demonstrated that pyric herbivory management and climate determine the impacts of grazing on tallgrass prairie systems. The contrasting seasonal forage availabilities in burned and unburned patches, indicated by different seasonality of EVI, also suggests that patch burning might better balance the quantity and quality of the grass available for cattle grazing. © 2019 The Society for Range Management
Scholarly peer-reviewed articles published by the Society for Range Management. Access articles on a rolling-window basis from vol. 1, 1948 up to 5 years from the current year. Formerly Journal of Range Management (JRM). More recent content is available by subscription from SRM.