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food production grew. In 13 years between 1962 and 1975, 32,000 new chemical products showed up on the market. In 1962, 730 million pounds of chemicals were produced; by 1975, the total skyrocketed to over a billion pounds.
According to Johnson, science is now into a new generation of chemicals — biological pest controls that act on a specific stage in the life cycle of an organism or attack only a certain species. Use of this third generation of chemicals is more than just a science, Johnson maintained. “It’s still an art form and may stay that way for a long, long time,” he said.
Later, he warned that biological pest controls could spread to effect beneficial as well as harmful insects. As an example, he cited chemicals that interfer with the normal development of an insect’s external skeleton. These chemicals are a help in controlling orchard pests but could prove damaging if spread accidentally to a bee hive.
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