For as long as farmers have been farming, they’ve battled animal pests, diseases, and weeds. These “agripests” pose obvious burdens to farmers, both financially and time wise. However, what many urbanites and critics of crop chemicals fail to realize is that these pests are a serious threat everyone – if farmers can’t control them, a lot of people could end up going hungry.
One of the worst famines in history (that wasn’t manmade) was caused by a pathogen called “Phytophthora infestans.” Better known as “potato blight,” a series of outbreaks of the disease starting around 1840 in Ireland led to the “Great Hunger” or “Great Famine,” a mass starvation event that killed some 1 million people in the country, and hundreds of thousands in neighboring Europe. Historical accounts talk of not just whole families dying, but entire villages being wiped out.
It’s estimated that between 1840 and 1855, the worst of the blight years, another 3 million Irish fled the country. All told, blight and famine saw the population of Ireland reduced by more than half, from 8.5 million in 1847 to around just 4.4 million by 1901. Historians today say many factors contributed to the Great Hunger’s depth of destruction and despair but the main culprit remains potato blight, a novel disease at the time that farmers were powerless to control.
During the early centuries of human agriculture, the causes of crop failures were a mystery, even for the 19th century’s Irish potato famine. It was the scientific investigations of potato blight that led to the discovery that plant diseases were caused by microorganisms. This in turn led to the birth of plant pathology as a science.
Scientists were already investigating pesticides by the 1800s. In the late 1800s, a California almond farmer invented a pressure sprayer that led to more efficient applications in crops. By the 1900s, the US enacted its first pesticide legislation, the Federal Insecticide Act (FIA) was enacted to protect farmers and consumers from fraudulent manufacturers, setting standards to ensure quality pesticides were produced.
Up until the 1940s, chemicals derived from plants and inorganic compounds were the source of pest control. During World War II, the synthetic compound DDT played a significant role in saving Allied soldiers from insect transmitted diseases and subsequently was hailed as the insecticide to solve all insect issues. At this time, synthetic pesticide production increased significantly, and the modern-day chemical industry was launched, thus starting a new era of pest control.
The widespread adoption of modern synthetic pesticides, beginning in the mid-20th century, was a major driver of the dramatic increase in global food production that occurred during the “Green Revolution”. Between 1961 and 2020, global agricultural output grew at an average annual rate of +2.3%. While many factors contributed to this growth, pesticides were a key component. Some sources estimate that without pesticides, there would be a stunning -78% reduction in fruit production, a -54% decrease in vegetable production, and a -32% decline in cereal production.
Pesticides also contribute to the sustainability of agricultural practices by allowing farmers to produce more food on less land, thereby conserving natural habitats and reducing the pressure to expand agricultural areas into ecologically sensitive areas.
It’s worth noting that “organic” food products are grown according to stricter standards when it comes to chemical usage. However, they are often understood by the public and farmers alike to be free from pesticides, but this is not the case. While organic farming avoids synthetic pesticides, it allows for the use of natural pesticides, which, like their synthetic counterparts, are designed to kill pests and can leave residues on product. They also break down more quickly and need to reapplied more often, potentially leading to a higher overall pesticide load compared to conventional farming. (Sources: With or Without You?—A Critical Review on Pesticides in Food, CSIRO, Phys.org)
