In pure form nobody applies diesel fuel to processing of an orchard, but mix with a large amount of water and other substances, reducing its destructive activity. But processing by the diluted diesel fuel can even be recommended in case the apple-tree or plum have an acute angle which with a current of years started rotting. In this case annual application of this substance can interfere with rotting processes.
Mechanical models it is much more convenient manual, but are several times more expensive and provided that the gardener has a small garden, are unjustified luxury. At the same time, the manual device demands created for processing of pears, plums, apple-trees and other representatives of an orchard of constant pressure which is provided with pumping by the gardener's hands. But also the principle of pumping at different devices the different: one devices work at preliminary pumping, and others ― at a constant. Each of these options has advantages and shortcomings. The gardener has to choose the model which is most suitable for itself.