It’s inevitable - if there are plants, there are going to be pests. Farmers, home gardeners, commercial growers, and food suppliers worldwide struggle to deal with the pests that compete for humankind's food supply or are simply undesirable.
As part of their efforts to rid growing areas of these pests, pesticides were developed. Pesticide is now used to refer to any number of devices, methods, or chemicals used to remove pests from plants and animals. To understand the reliance of growers on pesticides, it’s important to understand the development of both farming and pest removal.
Early Forms of Pest Removal
Since the advent of agriculture, man has been locked in a perpetual battle against pests that invade crops and wreak havoc on food supplies. The earliest farmers dealt with the invasion of pests with natural methods. For example, some farmers would plant their crops during particular phases of the moon.
Other farmers relied on crop rotation to reduce pest infiltration. By planting small amounts of varied crops, farmers were able to manage the number of pests. Ancient records suggest that farmers discovered naturally pest-resistant plants, and would grow those plants in abundance. Primitive methods also included picking pests off by hand, using scare tactics such as loud noises to chase away grasshoppers, or introducing natural predators to manage insect populations.
Introduction of Pesticides
While many believe that man-made pesticides are a recent development, the ancient Chinese were among the first to introduce the idea of applying chemicals to plants. In fact, farmers in the Middle East, Rome, and China were the originators of pesticide development.
In ancient times, Chinese farmers crushed the flowers of the pyrethrum plant, Middle Eastern farmers used sulfur to control their pest problems, and Romans used crushed arsenic to keep their crops safe. These methods were effective, but labor intensive. As the size and scope of farms grew, farmers needed more reliable and manageable resources.
It wasn’t until the 1840s that pesticides were used on a large scale. A fungus invaded Britain, and sulfur was successfully used to control the epidemic. Within thirty years, farmers were depending on mass-produced pesticides. For example, potato farmers in Colorado used paris green, a water-insoluble chemical that protected crops from the Colorado beetle.
Tar oil, quassia and other types of pesticides were used in limited quantities until World War II. Research conducted during that time led to the development of DDT and other substances, beginning a science devoted solely to the production of pesticides and other aids for farming.
Application of Pesticides
Early pesticide distribution was done manually, with farmers applying small quantities to specific zones or plants. The late 1800s introduced the large-scale application of pesticides through the use of giant machines. In the 1920s, airplanes were adopted as a means of covering large crop fields.
By the 1950s, regulations were in place to ensure low-flying, well-controlled application. Today’s pesticides are applied in a variety of manners, ensuring limited environmental impact, concentrated applications, and maximum efficiency.
As farms began producing larger crop yields and the demand for food supply increased, the demand for easier application of pesticides grew as well. Crop dusting, the application of large amounts of pesticide to large, flat growing fields via airplane, is still used in many parts of the world.
Hand-held applicators, held by workers as they walk through fields, are used in smaller settings or where more precise spray coverage is needed. Large, tractor-like applicators can be driven through fields to spray areas between trees or tall crops.
Integrated Pest Management
In the 1960s, the Integrated Pest Management process was developed to reduce dependence on chemical application and increase the effectiveness of pest removal. Integrated Pest Management (IPM) is the process of using multiple methods within a single farm.
IPM involves using chemical pesticides in addition to natural methods. These methods may include using bacterial, fungal, or viral insecticides as well as introducing natural predators and parasites. Many of the methods used are the same as those discovered by early farmers: crop rotation, using pest-resistant plants, and plowing at the most effective time are all still effective ways to manage pests and are still widely used today.
Another component of the IPM process may be to introduce sexual-attractant traps, sterilized male insects, or insects that have been genetically engineered to remain juveniles into the fields. Global use of pesticides varies as countries begin to capitalize on the development of newer, more efficient man-made products and as they find the correct balance of IPM to manage their region’s pests.
Man will continue to depend on farmers to supply the world’s foods, and farmers will continue to rely on pesticides to help maximize their crop yields. Scientific advances and developments will continue to increase effectiveness and reduce environmental impact as farmers and scientists work together to find sustainable solutions. As the world’s population increases, the demand for food will continue to grow, creating an increased need for pesticides and the benefits they bring to the farm.