Economic assessment of forage responses to mesquite control in the Rolling Plains of North Texas

Abstract

Encroachment of mesquite brush in the last 100 years has caused a major problem with rangeland in Texas. Many different methods to control brush problem encroachment have been used in the last 50 years, but no conclusions regarding the most economically viable method have been reached. The objective of this study was to determine the economic feasibility of three alternative mesquite control methods: aerial spray rootkill herbicide ($59.28/ha), aerial spray topkill herbicide ($37.05/ha), and controlled topkill fire ($6.18/ha). The objective was accomplished by collecting herbaceous production data in response to the alternative mesquite control treatments. This data was quantified and used to estimate the net present values and internal rates of return for each scenario from a deterministic standpoint. It was also used as a method of validating PHYGROW; a hydrologic based range plant growth simulation model. This model produced stocking rates for each year over the planning horizon, which was used as the source of variability for the stochastic analyses. The stochastic analyses returned probabilistic values for the net present values and internal rates of return for each scenario. The deterministic analyses and stochastic analyses produced similar results. Both indicate that brush management using prescribed fire was the "best" alternative followed by the rootkill herbicide treatment. They also agree that the topkill herbicide treatment was not an economically feasible brush management alternative.