Economic Assessment of Tebuthiuron-Fire Systems for Brush Management

Abstract

Economic performance of prescribed burning following aerial applications of tebuthiuron {N-[5-(1,1-dimethyiethyl)-1,3,4-thiadiazol-2-yl]-N,N′-dimethylurea} pellets was estimated for Texas whitebrush (Aloysia gratissima[Gillies & Hook.] Troncoso # ALYLY)-dominated rangeland and for post oak (Quercus stellataWangenh. # QUESL)-dominated mixed hardwood stands. Honey mesquite (Prosopis glandulosaTorr. # PRCJG) invasion largely negated differences in estimated beef production between treated and untreated pastures within 13 yr of controlling Texas whitebrush with tebuthiuron at 2 kg ai/ha. American beautyberry (Callicarpa americanaL.) and other shrubs increased such that the woody canopy cover was 87% of the original canopy 7 yr after applying tebuthiuron at 2.2 kg/ha to a heavy cover of oaks-mixed hardwoods. Burning at 2- to 4-yr intervals after tebuthiuron applications suppressed invading shrubs and increased projected internal rates of return by about 2% for each burning, compared to herbicide application only.