Commentary on “Effect of brush control on evapotranspiration in the North Concho River watershed using the eddy covariance technique” by Saleh et al. (2009)

Excerpt

In a paper “Effect of brush control on evapotranspiration in the North Concho River watershed using the eddy covariance technique,” published in the September/October 2009 issue of the Journal of Soil and Water Conservation, Saleh et al. argue that clearing mesquite has “great potential” for increasing water yield in the North Concho River watershed near San Angelo, Texas. The clear implication is that shrub removal is a viable strategy for increasing water supply to the city of San Angelo. The authors make this argument mainly on the basis of the small differences in evapotranspiration rates they measured between pastures with mesquite and those without mesquite.

We do not dispute the fact that the timing and amount of evapotranspiration may be affected by differences in tree cover and density, but we do not agree that these modest differences will translate to meaningful changes in water supply. There is already overwhelming evidence that brush management in the North Concho watershed will not lead to increases in water flow in the North Concho. A brush control project was begun in the North Concho watershed 10 years ago, and even though this period included one of the wettest years on record (2007), there has…