Weeds, Corn, and Drinking Water: An Interconnected History of Industrialized Corn in the U.S. and West Germany

Corn in Industrialized Cropscapes

Just before landing in Minneapolis, Minnesota, in the winter of 2017-2018, I was lucky to catch a beautiful view of twenty-first century agriculture: a patchwork of flawless rural rectangles, perfectly aligned. In other words, a cropscape.[1]

Such fields have developed throughout the twentieth century as a result of rationalization, specialization, and mechanization of agriculture. While this generated high yields and less fluctuation in crop quality, industrial agriculture also caused a variety of unintended environmental consequences, which began to appear in the 1950s. My research takes a deeper look into the use of chemical weed killers in twentieth-century corn production and their effects on ground and drinking water in the United States and West Germany. Despite differences in scale, size, and organization, German agriculture is fundamentally based on U.S. ideas of twentieth-century agricultural production: achieving high yields with hybrid seeds and substituting human work with the use of machinery, synthetic pesticides, and artificial fertilizers. 

A black-and-white photograph showing a machine driving over a field, spraying atrazine on the crops.
Spraying Gesaprim (atrazine) after corn emerged in 1965. Johannes Zscheischler and Friedrich Groß, Mais: Anbau und Verwertung (Frankfurt a.M.: DLG-Verlag, 1966), 54.
[Image description: black-and-white photo that depicts a farmer driving a crop sprayer through a corn field.]

Corn in West Germany

Before the Second World War, only a few farmers in the south of Germany grew corn. Those who did grew it at a very small scale to add to their animal feed. Most German farmers did not even know anything about this plant when sacks of U.S. hybrid corn seed crossed the border into West Germany as part of the European Recovery Plan (ERP) in 1947. Supported and encouraged by the German and U.S. Departments for Agriculture, the United Nations and other private, public, and federal institutions, U.S. breeders exchanged their corn-growing knowledge with West German agronomists and breeders. [2]

One crucial element of convincing German farmers to start growing corn was the method of weed control. Weeds take away nutrients, space, and light from the young corn plants, so preventing their growth was an important and obligatory task to achieve high yields, and it had to be done several times throughout the growing season. But mechanical solutions of weed killing, either done by hand or by hoe, were often unaffordable during times of declining numbers of agricultural workers. The chemical industry, encouraged by the success of substances like DDT to kill insects a decade earlier, increased their research on herbicides—chemicals that can kill weeds. In 1958, a group of chemists from J.R. Geigy Ltd. in Basel, Switzerland synthesized the herbicide atrazine.[3] The chemical removed all weeds from corn fields and showed no effects on the corn plant, even when applied in high doses. 

From this point, West German agronomists and agricultural scientists strongly recommended growing corn with atrazine. As a result, West German corn acreage grew rapidly throughout the 1960s, with 95% of corn acreage sprayed with the herbacide. 

A graph showing the development of crops for animal feed in West Germany.
Development of crops for fodder in West Germany between 1968 and 1988; Silomais = corn for silage; K.-Mais = corn to feed. Johannes Zscheischler et al., Handbuch Mais: Umweltgerechter Anbau, wirtschaftliche Verwertung (Frankfurt a.M.: DLG-Verlag, 1990), 24.
[Image description: a graph with various lines and symbols to depict development of crops for fodder.]

Atrazine in the Environment

Increased use of atrazine in corn—and, in the West German case, also on the train tracks of the Deutsche Bundesbahn—had immediate unintended consequences. Farmers in the 1960s in corn-growing areas throughout the United States and Europe witnessed severe damages to some crops grown on land previously planted with corn and treated with atrazine. Atrazine was chemically active in the soil longer than expected. It soon became clear that if atrazine did not fully degrade in the soil, the chances were high that the substance could leach into groundwater. Regional monitoring programs were established at the end of the 1960s in the U.S. Corn Belt as well as in areas of West Germany. Scientists continued to collect atrazine data throughout the 1970s. By the end of the 1980s, research on atrazine had surpassed that done on any other pesticide, including DDT. The results overwhelmingly proved that the chemical remained in the soil long enough to seep into water systems. It was only a matter of time that atrazine residue would mix into the tap water of private homes in corn-growing areas. 

Political Decisions on Environmental Risks

Atrazine residue appeared in drinking water around the world starting in the mid-1970s. This prompted another global wave of studies on the chemical’s toxicity and potential harm to human health if consumed in low doses. While the controversy over atrazine’s effects on human health is still going on today, there is no doubt that residue still exist in drinking water. 

The debate over water purity and acceptance of anthropogenic substances in water reached its peak in Europe at the end of the 1970s. Referring to the “precautionary principle” (basing decisions on potential risks and “non-knowledge”), the European Union released a guideline for drinking water purity in 1980, where it established a zero-tolerance policy for pesticide residues altogether.[4] With a threshold of 0.1 parts per billion (ppb) per substance and 0.5 ppb of all pesticides in drinking water, the EU chose a scale that was not even technically measurable for most substances in use. In doing so, it made a clear statement: pesticides should not be in drinking water—no matter their effect on the human body. 

Throughout the 1980s, industrial chemists, agronomists, and regional departments of agriculture worked together to find ways to reduce atrazine residue in West German bodies of water: applying it at different times to minimize leaching, using limited amounts of the active substance, and establishing atrazine-free zones around drinking water wells. Despite many attempts to meet the EU’s threshold, scientists determined that they could not control atrazine from seeping into water sources. In 1991, departments of agriculture, economy, and environment across Europe decided to ban atrazine from the pesticide market entirely.

Outside of Europe, atrazine is still one of the most commonly used herbicides. In the United States, the maximum contamination level of atrazine in drinking water was set to 3 ppb in 1991, and agricultural use of the substance has been accompanied by continuing monitoring programs of its residues since the 1970s. For example, in the areas I flew over a few years ago, the Minnesota Department for Agriculture collected data on atrazine in groundwater since 1985. Atrazine is considered “a groundwater ‘common detection’ chemical […] and a pesticide of concern for surface waters,” but its concentrations are typically below the threshold.[5]

Thus the debate over atrizine’s health impacts continues.

[1] Cropscapes is a concept currently in the making at the Max-Planck-Institut for the History of Science in Berlin by Francesca Bray (University of Edinburgh), Barbara Hahn (Texas Tech University), John Bosco Lourdusamy (Indian Institute of Technology Madras), and Tiago Saraiva (Drexel University). “By cropscape we denote an assemblage formed around a crop, the heterogeneous elements deliberately or fortuitously brought together in a specific location and moment to make and grow a crop: plants, people and pests; technologies, skills and ideas; tastes and markets; environment and biology; labour and capital; labour regimes.” Tiago Saraiva, John Lourdusamy, Barbara Hahn, and Francesca Bray, “The Republic of Plants: Plant Agency in the Movement of Cropscapes,” session proposal for the Annual Meeting of the Society of the History of Technology (2017).

[2] See e.g. Johannes Zscheischler, “Wie mich das Maisvirus befallen hat,” Mais: Die Fachzeitschrift für Spezialisten 17 (1989): 26-29.

[3] The history of this pesticide company is fairly complicated. J.R. Geigy Ltd. originated in 1758, becoming a “Ltd” in 1914. “J.R.” are the initials of its founder, Johann Rudolf Geigy. J.R. Geigy Ltd. is the same company that synthesized DDT. The corporation later changed their name multiple times, merging with several global players until it became Syngenta in 2000, and purchased by ChemChina in 2017.

[4] For the precautionary principle (Vorsorgeprinzip) in Europe, see e.g. Ursula Marti, Das Vorsorgeprinzip im Umweltrecht: Am Beispiel der internationalen, europäischen und schweizerischen Rechtsordnung (Zurich: Schulthess Verlag, 2011).

[5] Under Minn. Stat. Chapter 103H; see also Atrazine Special Registration Review FAQs on the website of the Minnesota Department for Agriculture.

*Cover image: A view of Minneapolis, Minnesota from the window of an airplane. Photo by author.

[Cover image description: A view from an airplane window. The sky is clear and blue. The ground looks like a patchwork, with squares of farmland with two rivers cutting across.]