Conservation is often portrayed as a battle between environmentalists and polluters, but this perspective can overlook the complexity of the issue. What happens to conservation when ideas about nature transcend political boundaries? In my book, “Chemical Lands: Pesticides, Aerial Spraying and Health in North America’s Grasslands since 1945,” I examine how pilots, scientists, and farmers refined “cropdusting” techniques on the Great Plains after World War II. This industry emerged well before Rachel Carson’s 1962 publication of “Silent Spring,” which criticized the widespread use of synthetic pesticides. Chemical companies touted these substances as “miracle” solutions, often glossing over potential risks. In contrast, pilots and scientists approached the situation with caution. Even before a national environmental movement took hold, local producers began their own investigations into safety and health concerns as early as the 1950s. While meeting production demands with pesticides was often necessary, they sought to understand the related risks.
Following World War II, U.S. farmers started using new chemicals, many developed during the war, to combat pests like grassland weeds and insects such as corn borers. As markets expanded during the postwar economic boom, pesticides were seen as a ready solution. Companies like DuPont and Dow assured farmers that, just as insecticides like DDT had protected soldiers from diseases during the war, they could also protect crops at home. However, many cropdusting pilots, referred to as “ag pilots,” and agricultural scientists from land-grant universities did not fully accept these assurances. They were concerned that the risks of using pesticides could be as severe as not using them. Seeking answers, these individuals attended annual conferences at universities and rural convention centers. Events like the North Central Weed Control Conference, which began in 1944, provided a forum for learning about new developments and discussing existing methods. Records of these conferences reveal an evolving sense of “chemical stewardship” on the Plains. Farmers and experts were often acutely aware of their limited knowledge about the impacts of pesticides and herbicides. In a plenary speech at the 1947 NCWCC meeting in Topeka, Kansas, University of Nebraska agricultural extension scientist Noel Hanson warned of the challenges in managing agricultural chemicals:
“We all know that it will take years of research, education, regulation, manufacture, distribution of materials, and plain good farming in a sound agriculture and industry before the weeds that are now present can be most efficiently and economically brought under control. Little progress can be made until the biological foundations … are better known.”
Reporter Dick Mann noted in the Kansas Farmer that wheat farmers were also apprehensive about the new pesticides and the potential effects of aerial spraying. He wrote: “These chemicals compare with some of the new miracle drugs in medicine. They have the power for tremendous good, but they also have the power for great harm if improperly used. … With this information as background you can see that many persons are deeply concerned over the possibilities of this thing getting out of hand.”
In Hays, Kansas, pilot Donald E. Pratt, dubbed the “Spray King of the West,” founded the P-T Air Service, an aerial spraying school combining spraying education with agricultural science. Pratt ensured his pilots thoroughly understood the latest pest control chemicals available. His team collaborated with state entomologists and weed scientists to gain insights into crop-pest dynamics, and Pratt personally conducted experiments on private test plots to evaluate effectiveness and dangers. Pilots across the Great Plains established similar flight schools. However, some operators took shortcuts. These renegade pilots neglected factors like wind direction, resulting in numerous chemical poisonings in the fields and surrounding communities. Some suppliers developed a method called “incorporating,” which involved mixing various pesticides and mislabeling them as different products. These adulterated poisons either excessively contaminated fields or were ineffective against pests, tarnishing the reputations of ag pilots. Nonetheless, reputable weed scientists and ag pilots continued to investigate aerial pesticide application risks. They also took measures to curb unscrupulous practices, like designing certification documents for the industry and supporting aerial spraying regulations.
Then came Rachel Carson’s widely read book. In “Silent Spring,” a major question was about the methods used for applying agricultural chemicals, particularly insecticides. Carson did not advocate for an outright ban on widely used insecticides or suggest that farmers completely cease using chemicals. However, she highlighted indiscriminate aerial spraying as a prime example of the significant ecological hazards posed by DDT and other agricultural chemicals: “Although today’s poisons are more dangerous than any known before, they have amazingly become something to be showered down indiscriminately from the skies. Not only the target insect or plant, but anything human and nonhuman within range of the chemical fallout has known the sinister touch of the poison.”
According to Carson, health was holistic, encompassing humans, wildlife, and the environment. She held both producers and the chemicals they employed accountable for threatening all forms of life. Farmers, ranchers, livestock, crops, water supplies, and cities were all at risk. “Silent Spring” spurred calls for regulation in the 1960s and 1970s, resulting in the establishment of the Environmental Protection Agency in 1970 and the ban on DDT in 1972.
Many ag pilots resisted these changes, arguing that they had already devised practical methods to minimize risks. While they acknowledged the dangers of pesticides, they also pointed out the risks posed by pests. Safety and protection on farmland required “safe,” “standardized” use of agricultural chemicals. Following the ban on DDT, newer and more toxic alternatives emerged, such as organophosphates and, more recently, neonicotinoids. However, pests and weeds have developed resistance to each successive generation of products. Currently, many farmers are grappling with weeds that have become resistant to the widely used herbicide glyphosate, marking the latest phase in this cycle of chemical and pest challenges.
Agricultural chemicals remain a staple of conventional farming, and aerial spraying is still widely practiced on large-scale farms across the Great Plains. Many pilots and farmers continue to engage in chemical stewardship, employing GPS technology to accurately apply pesticides and ensure they use no more than necessary.