Patch Burning: Integrating Fire and Grazing to Promote Heterogeneity
Heterogeneity refers to the differences in habitats across the landscape, and it is required for diverse plant and wildlife communities. Some heterogeneity is inherent, caused by differences in soils, while most heterogeneity is disturbance driven. Climate, fire, and grazing are the main three disturbance factors that have historically shaped the landscape. All three are still very important to the continued diversity and health of the plants and animals associated with our prairies, shrublands, and forestlands across the Great Plains. While we cannot control the climate, we can manage grazing by stocking rate, season of use, and kind and type of animal. Fire can also be managed by frequency, season, and weather conditions. To keep biodiversity intact, these disturbances should be considered collectively, rather than independent of each other.
Fire alone cannot maintain the heterogeneity necessary for rangeland health, but fire with grazing is important in the creation and maintenance of the diverse habitats needed to support the numerous plants and animals across the land. Grazing distribution and habitat selection by feeding animals is determined by decisions made at multiple levels:
Landscapes (i.e. Tallgrass Praire) -> Communities (i.e. upland site) -> Patch (i.e. burned area) -> Feeding Station (i.e. site within burned area) -> Plant (i.e. Indiangrass) -> Plant Part
From historical fire and grazing patterns we know that animals preferentially select burned areas and graze them heavily. When another area was burned, they shift their utilization to this new patch. This allows the previously burned and closely grazed patch to rest until adequate fuel had grown back, which allowed the next fire event. This fire-grazing interaction would create a shifting mosaic over the entire landscape that was critical to the conservation of biodiversity.