FIELD: chemical treatment of agricultural lands by means of flying vehicles; treatment of large tracts of forest for protection against pests. SUBSTANCE: method includes treatment of field at subsequent approaches of helicopter from opposite sides. Specific feature of said method consists in treatment of agricultural lands by solution (emulsion, suspension) of definite concentration at definite flow rate, working width of coverage and flying speed determined from mathematical formulae including record of concentration of working agent in solution, length and width of field being treated, flow rate of solution, working width of coverage and indicated flying speed. EFFECT: enhanced economical efficiency and ecological safety. 1 ex
