FURTHER to Rosemary Goring's article on the declining insect population ("We need a battle plan now if we are to save the planet", The Herald, February 13): as long as we allow chemical companies to manufacture pesticides and herbicides, and farmers to spray them over every field, we have problems. In the 1960s Rachel Carson described exactly what was happening to the insect population, but chemical companies tried to silence her. Her book Silent Spring was published just before she died of cancer.

Margaret Forbes,

Corlic Way, Kilmacolm.