OCR Text |
Show Agency. The information obtained by the study on the present levels of pesticide residual in return flow in the Unit area will serve as baseline index for future conditions. The study revealed the present level of contamination is low in the Utah Lake drainage area and DDT levels in the fish tested were 0.05 to 0.09 Wm> well below the Federal standard of 5 to 7 ppm for edible fish. 1^ Insecticides Insecticides are toxic to man, livestock, and wildlife and should be used and stored carefully and according to the manufacturer's instructions. It is known that there are many hundreds of insects common to a cropped field. Of these, only a few are considered harmful and cause damage to the crop. It is important that the farmer identify the insect and determine the actual or potential effect of the insect on the crop before the use of insecticide. State extension services, universities, and several private companies have expertise to assist the farmer in identification and solution of the insect problem. Several different insecticides have been or are presently being used in the Bonneville Unit area. Representative of these are:. BHC ( lindane), Heptachlor, Aldrin, Dieldrin, and DDT. Almost all uses of DDT have been cancelled and should not be used any longer. BHC is seldom used any more because it leaves a bad taste on products. All uses of lindane, Heptachlor, Aldrin, and Dieldrin are under review by the Environmental Protection Agency and will probably be phased out of agricultural use in the near future. It is expected that the use of insecticides would increase under Unit conditions as additional acreage was brought into production. On the other hand, it would be expected that the adverse effects of the use of these chemicals would be reduced by the use of low or nonresidual sprays and dusts and by the use of alternative measures such as timely cultivation and harvest, the introduction of sterile male insects to control reproduction cycles, the development of resistant plants and the introduction of new plants, and the protection of known insect predators. Overall the impact of the additional use of insecticides associated with the Unit development would be minor. Herbicides Herbicide residues in soils may cause injury to sensitive crops. This injury can be avoided or minimized by using only the 402 |