On this date 50 years ago, Rachel Carson’s Silent Spring was published, launching a new awareness about the environment and pesticide use. As many of you have probably already read on the many articles about this subject that have appeared in the past few weeks, her book sparked a hot controversy about the use of pesticides. Many in IPM professions credit her with bringing attention to the concept of integrated pest management.
Carson grew up in rural Pennsylvania and learned from her mother how to appreciate nature and wildlife. She majored in marine biology and later received a masters in zoology, but her scientific degrees led her instead to a career of writing rather than scientific research. She wrote pamphlets and press releases for the U.S. Bureau of Fisheries (now the U.S. Fish and Wildlife Service) and on the side wrote articles designed to lead people into the same sense of wonder that she had about the natural world. (Rachelcarson.org)
Shortly after World War II, Carson began to question the widespread use of pesticides. In the mid-1940s, two of Carson’s colleagues wrote scientific papers about the dangers of DDT, and Carson approached the Reader’s Digest about an article about DDT, but the magazine declined. Carson did nothing else about the idea until 1957, when a friend wrote to tell her that airplanes spraying for mosquitoes were flying back and forth over her wooded yard. The next day she noticed dead birds in her yard and wanted to know if the Fish and Wildlife Service could stop the sprays. For the next several years, Carson researched for and wrote what would become Silent Spring. (A Science Odyssey)
Although Carson is credited with being the major reason for the cancellation of DDT (for which many have lambasted her, citing thousands of deaths to malaria because of the book), Silent Spring served only to call attention to the overuse of pesticides. In fact, by the time of Carson’s book, scientists were beginning to document widespread resistance to DDT. By 1947, even before DDT was abundantly used during WWII, scientists documented resistant houseflies in Europe. By 1949, mosquitoes resistant to DDT were being reported on two continents. By the time DDT was banned in 1972, 19 species of mosquitoes capable of transmitting malaria were resistant to DDT. (Berenbaum, “If Malaria’s the Problem, DDT’s Not the Only Answer”)
Silent Spring did usher in the official development of integrated pest management as pest population management concept. In the late 1960s, entomologists at the University of California introduced IPM as a multi-strategy pest management system. The Huffaker Project of 1972 introduced the idea of IPM cooperative research, coordinating USDA Agricultural Research Service, the Forest Service and the Cooperative State Research Service.
While Carson did not actually advocate for a total ban on pesticides, she did question their exclusive use. In fact, her concerns have been backed by scientific evidence for years. Weed scientists have recently been searching for alternatives to glyphosate, which was long used as an exclusive weed control strategy, as more and more weeds become resistant to the chemical. Much funding for IPM goes to researchers who try to find time-efficient methods to managing pests to prevent them from becoming resistant to insecticides. Plant pathologists at the University of Georgia and Clemson University have used funding to develop a test for fungicide-resistant peach brown rot to help growers choose an effective fungicide.
Although pesticide resistance is primarily responsible for the development of IPM, Silent Spring may have helped it to be more accepted. Public skepticism of pesticide overuse is still very much alive, as the increasing popularity of organic foods suggests, making IPM an ever-important strategy in agricultural production.
Berenbaum, M. 5 June 2005. “If Malaria’s the Problem, DDT’s Not the Only Answer.” The Washington Post. Online: http://www.washingtonpost.com/wp-dyn/content/article/2005/06/04/AR2005060400130.html.
Silent Spring is published. 1998. A Science Odyssey: People and Discoveries. Produced by WGBH for PBS. Online at http://www.pbs.org/wgbh/aso/.
Rachel Carson Biography. Online at rachelcarson.org.