The United States government has been making legal and appropriate decisions for the welfare of man for years. They've been making decisions about the things we own, how we live day to day, even how we drive. But one of the most important decision making is based on the health of the citizens. Chemicals we use, foods we eat, and the insect population are some concerns that enter this category of health issues. Some of the biggest questions we may ask ourselves are: How much are the insects affecting our agriculture? How can we stop them from destroying plant growth? Will that do more damage than good?.
Crop losses from insects and other biological competitors are unquestionably important. What value we may assign to their alleviation is not always clear. But the extent of loss is now at least partly measurable. The losses to pests are usually based on "before and after" estimates, or, or less often, actual yield figures. Yield changes may be translated into dollar gain or loss, and hence provide the only good measure of the worth of a pest control procedure. Even at that, they do not represent the only measures of worth that can be applied. What is meant by loss must first be made clear. It is one thing to recognize that losses occur, another to do something about them, and still another to determine whether the alleviation of loss is necessarily socially advantageous.
In 1940-44, one of the best-known fruit pests, the codling moth, caused an annual loss of 15 per cent of American apple crops, or about $25 million (Haeussler, 1953). The cost of control was perhaps the same. In 1944 to 1948, the annual loss was about 4 per cent, or about $9 million dollars. The marked reduction in loss was due almost entirely to the widespread use of DDT. However, insecticide resistance and rise in spider mites as pests, because of DDT, might be charged against the DDT gains (Pesticides and the living landscape-Robert L.
