Abstract: A measuring, mixing and spraying apparatus for a tractor is a combination of, generally, four distinct component parts. The entire apparatus is operated under pressure from a compressor mounted onto the front of the tractor. Along one side of the tractor is a diluent storage tank which provides storage on the tractor for the diluent used to dilute a test sample being sprayed. Connected to the storage tank is a diluent measuring tank specifically designed to receive a predetermined amount of diluent from the diluent storage tank. The diluent measuring tank is connected to a diluent mixing tank, and in this mixing tank the measured amount of diluent from the diluent measuring tank is mixed with a specific quantity of the test sample. The diluent mixing tank in turn, leads to a spray boom which disperses the diluted and mixed test sample.