A prototype system was designed to inject dry flowable formulations directly into the hydraulic conduit of a liquid spraying system. Representative samples of dry flowable pesticides were obtained to evaluate parameters which affect liquid dispersion and metering characteristics of each material. Laboratory tests were conducted to quantify the dispersion times of the formulations at labeled rates. Preliminary tests indicated that the dispersion times for packaged formulations were lengthy, but reduced with increased amounts of agitation. Reduction of formulation particle sizes was investigated to determine effects on dispersion times. Tests were performed to evaluate the accuracy and repeatability of the metering unit with different pesticide formulations. A laboratory test apparatus was assembled to evaluate the overall performance of the system on an agricultural sprayer. Tests involved the collection of pump effluent to determine the compatibility of the unit with field sprayers equipped with hydraulic nozzles which can accommodate dispersible granular formulations.