Results are described of field research conducted at the University of Nebraska Evapotranspiration Research Facility at Mead during the growing seasons of 1969 and 1970. Advances in analytical methods and instrumentation achieved are also described. Windbreaks were shown to markedly reduce the water use by irrigated soybeans with no significant reduction in photosynthetic rate. The watersaving effect was particularly important on days of strong regional advection of sensible heat. Instrumentation developments and field studies during 1969 and 1970 now provide the methodology needed for accurate estimation of CO2 flux rates in the field. These methods depend upon lysimetric determination of the exchange coefficient for water vapor. Sensors for the measurement of net radiation in plant canopies, temperature and humidity gradients above canopies, albedo, surface temperature and CO2 concentrations and gradients were developed or improved. Sufficient data were assembled so that probability statements of daily water demand can be made for use in models of regional hydrology, for current water distribution decision making and for use by irrigators on their individual farms. (Author)