IMPACTS OF PATCH-BURN GRAZING ON BOTANICAL COMPOSITION OF THE TALLGRASS PRAIRIE
Rensink,* C.B.1; Fick, W.H.21District Extension Agent, K-State Research & Extension - Central Kansas District, Minneapolis, KS, 67467
2Associate Professor and State Extension Range Specialist, Kansas State University - Department of Agronomy, Manhattan, KS, 66506
Abstract:
Patch-burn grazing is a relatively new concept in terms of rangeland management. While this system has been promoted as a way to increase heterogeneity and wildlife habitat, preserving the integrity of the native tallgrass prairie is critical. In 2006, 253 ha at the KSU Bressner Range Research Unit in Woodson County, Kansas were subjected to spring patch-burn grazing (using one-third portions) and traditional full-burn grazing. Each treatment within the split-block design was replicated four times for 3 years. The objectives were to monitor the health of the prairie through botanical composition using modified step-point and to determine if a 3-year patch-burn cycle allows enough rest for the initial prescribed burn portion to recover. The mean changes in percent composition were analyzed by calculating 90% confidence intervals. Results of the study show that, while forb and woody plant composition did not differ between treatments, statistical differences (p<0.10) in grass composition existed. Total annual grasses increased 19.1 percentage units under patch-burning and 2.1 percentage units under full-burning, while total perennial grasses decreased 18.4 and 1.1 percentage units, respectively. When evaluated by treatment area (one-third portion), results indicated that the first 3-year cycle did allow enough time for recovery. At 2 years after treatment (2-YAT), no significant difference in composition (p>0.10) existed between the first patch-burn portions and the full-burn pastures. Patch-burn grazing may be attractive to those land managers who are seeking to potentially enhance the biodiversity or heterogeneity in portions of their operation without having to commit to a long-term approach.