• Sundaram, K. M. S.
  Chemical Control Research Institute, Ottawa, Ontario
  

Organophosphorus insecticides are becoming increasingly important for the control of insect pests in Canadian forest spray programs. Fenitrothion (0, 0-dimethyl 0-(4-nitro-m-totyl) phosphorothioate) has been used since 1969 in place of DDT for operational control of spruce budworm (Choristoneura fumiferana Clemens) without causing any gross damage to the forest flora and fauna (Fettes 1968). Yule and Duffy (1972) observed that when the insecticide was applied aerially in New Brunswick forests at the rate of 4 oz/acre, it disappeared rapidly from mixed spruce foliage with a half life of ca 4.5 days but persisted in trace amounts up to a year whereas in soil it disappeared within 32 days.

So far no information is available on the distribution and persistence of the compound in aquatic environments of forest areas. This report summarizes an operational experiment carried out in Larose Forest to study the persistence of aerially applied fenitrothion and its metabolites (the oxon analgue and 4-nitro-cresol) in white spruce foliage, soil and water samples collected from sprayed areas.