main line is mounted with flat fan nozzles placed at 25 cm distances the condensed arrangement of nozzles provides a triple overlapping of the spray at each spot on the soil thus forming a uniform continuous film the nozzle specification as described below allows for adjustment of the sprayer the second spraying line on the boom is for the purpose of covering the aisles between the beds when full coverage of the field is needed this applies mainly when the beds are narrow such as in potato production for soil solarization or for preventing soil erosion the nozzles on this line can be moved along the line to adjust the spacing according to specific bed width the nozzles on this line should be flat fan with a narrow angle pattern to spray only the aisles nozzles on the main boom may be with a wide angle pattern 95 u00b0 110 u00b0 or a narrow angle pattern 65 u00b0 80 u00b0 and capacity of 1 2 l min according to the field specification when applying the mulch on sandy soil a high level of smooth surface can be accomplished therefore a wide angle nozzle type is used if spray is applied on loessial or clay soil then soil surface is more grainy in such cases a narrow angle nozzle type is used with the same capacity this provides larger droplets for better coverage of the grainy surface and for forming the film at the desired volume of spray the flexibility of the nozzle type to be used gives the advantage of adjusting boom height according to field conditions over sprinkles and weather wind as noted a two coat spray is applied these two coats may be applied in two consecutive passes the preferred application is.