Selecting a nozzle

• Select ground speed (rate of travel) to be used.
• Determine the distance between tree rows.
• Decide gallons of spray wanted per acre based on tree size, material to be applied, and efficient operation of your sprayer.
• From Table 3-1 determine spray output per minute needed for the entire sprayer (two sides). For example, to apply 50 gallons of spray per acre at 2 mph, 4.0 gallons per minute will be needed for rows 20 feet apart and 6.1 for 30-foot rows. If one-side delivery is used, the amount needed is one-half the amount in the table.
• Consult the dealer or the operator's manual for capacity of discs and whirlers, after determining the pressure at the nozzle outlet. Then select those needed to give the desired output per minute, with conventional air-blast sprayers, nozzles should be selected and installed to allow delivery of 85 percent of the spray volume to the top two-thirds of the tree; 50 percent of the spray volume should be delivered to the top third of the tree. Sprayers with air-shear nozzles should be adjusted for similar distribution. Tower air-blast sprayers should have even or nearly uniform nozzles with slightly bigger ones on the top. On full dwarf and trellised trees, the nozzles can be nearly uniform since all parts of the trees are about the same distance from the nozzles. Table 3-2 illustrates how various combinations of discs and whirl plates can be used to achieve a wide range of flow rates. See your sprayer dealer or company representative for a complete range of choices.