Engineering and ecological evaluation of antitranspirants for increasing runoff in Colorado watersheds

Abstract

Experiments were performed in the laboratory and in the field to determine the effectiveness of 3 different types of film forming antitranspirants in reducing the evapotranspiration from phreatophytes, with·special emphasis on salt cedar. The antitranspirants tested in this study were Mobil-Leaf [Mobil Chemical Co.], wilt proof [Nursery Specialty Products] and XEF-4-3561 [Dow Corning Corp.]. The laboratory experiments indicated that a single antitranspirant.treatment can reduce the water loss from salt cedar by as much as 50% for several days and that the long term effectiveness of Mobil-Leaf is significantly better than that of the other two antitranspirants. None of the plants treated with Mobil-Leaf showed any discoloration or other physiological injury within a month after treatment. Field studies were conducted in cooperation with the Bureau of Land Management at the BLM Evapotranspirometer Installation at Bernardo, New Mexico with Mobil-Leaf. The·decrease in evapetranspiration from salt cedar observed in the field was less than that in the laboratory and current indications are that the resulting water savings was probably somewhat less than 30%. It is possible that the differences between laboratory in-field effect is due to a lack of uniformity and thoroughness of the spray covering.