Effects of film-forming antitranspirants on rates of transpiration and photosynthesis were evaluated by leaf chamber studies using dew-point hygrometer and infrared gas analyzer to monitor water vapor and carbon dioxide content of the air stream. Promising antitranspirant materials were evaluated as to foliar coverage with the aid of a scanning electron microscope, evaluated as to techniques of application, influence of stomatal conditions, plant-water potential and transmission of photosynthetically active wave lengths of light. Various antitranspirants were also field tested for possible use in highway landscaping, extension of life of cut flowers, aid in survival of transplants and cuttings, and improvement in fruit quality. Possible use of antitranspirants in reducing water loss by phreatophytes without destroying vegetation and ecological balance were also considered. Portions of this document are not fully legible.