Some considerations on the choice of a field sprayer1

An analysis comparing conventional and air-assisted sprayers indicates that even over relatively small areas air-assisted spraying offers advantages of both economics and efficacy. An analysis of Danish meteorological data from 1989 to 1991 indicates that, without including any savings on plant protection products, air-assisted sprayers proved most economic at total sprayed areas of over 600 ha, which with a typical Danish rotation equals a farm area of approx. 160 ha. Danish users of air-assisted sprayers claim reduction in their use of plant protection products of 25-30%. If more modest reductions of only 20 or 10% are considered, the break-even occurs at total sprayed areas of only 300 or 200 ha, equalling typical farms of 77 or 52 ha, respectively.