2,4-D for Post-Emergence Weed Control pressures the spray delivery angle of this nozzle will vary from 52 to 94 degrees. Fig. 11.-Commercial types of fish-tail nozzles. Principal parts of one nozzle are shown at right. The factors influencing the height at which the nozzles should be placed above the tops of the weeds are illustrated in Figure 13A. The four nozzles described in Figure 12, with angles of spray delivery of 650, 800, 950 and 110" at 40 pounds pressure per square inch, will cover a swath of 25.5, 33.6, 43.7 and 57.1 inches, respectively, when the nozzle is located 20 inches above the tops of the weeds. High nozzle placement may allow an undesirable modification of the spray pattern by wind.