By 1940 in the United States, the average farmer barely provided for ten people, but forty years later, that same farmer provided for over 100 people. During that time period, the number of farm laborers decreased sevenfold, and the number of farms decreased from seven million to two million.(Figure 1)[i]. How did this happen? The most direct answer is the application of technology to agriculture. Technology in the form of research, equipment, and hybridized seeds (known as precision agriculture) allowed for a linear increase in high yielding crops that is still observed today. The transfer of technology to agriculture was implemented by Norman Borlaug, who is known as the ‘Father of the Green Revolution.’[ii] He is credited with saving over a billion lives, primarily in Mexico and India. By comparing the current food production and the rate of population growth in the 1940-1950s, it was clear there would be a shortage of food unless food production increased. With the methods of the Green Revolution, Mexico and India introduced high yield varieties that allowed for each country to provide for its population. As the world’s current population continues to grow as expected, food production must continue to increase. Currently, enough food exists to feed the world, but food distribution problems result in multitudes going hungry. Food distribution problems must be addressed moving forward; however, unless we continue to improve farming and yield outputs through precision agriculture, we will not even have enough food to feed the world.
Farming before the 1940s differs from modern farming through one input: fossil fuels. Since 1940, fossil fuels have been used to develop fertilizers, insecticides, herbicides, hybridized seeds, and equipment. The mechanization of farming that began with the Green Revolution marked a significant input of fossil fuels. Planters, sprayers, windrowers, combines, and other tractors were the reason the number of farm laborers decreased sevenfold during the Green Revolution. The new equipment completed the same amount of work as hundreds, if not thousands, of laborers in less time. In the United States, nearly half of the wheat was imported in 1940; however, by 1950s and 1960s, it became self-sufficient and an exporter of wheat, respectively, as a result of the Green Revolution.[iii] Precision agriculture began with the practices introduced in the 1950-1960s and resulted in high yielding crops (Figure 2).
Precision agriculture and its practices aim to make farming inputs as efficient as possible, reduce costs, and minimize environmental impact. Nonrenewable resources in the form of fossil fuels and materials are often used, but precision agriculture strives to develop the best solution with the materials available. In the past, new technologies have been readily applied to agriculture. For example, GPS was used in farming tractors years before it was used in cellular phones. Differential GPS is used in farm equipment to improve efficiency and minimize the use of fossil fuels. Satellites drive the tractors along straight lines to reduce overlap on the subsequent passes, meaning the tractor covers almost entirely new ground with each pass. This means the field is completed faster with less fuel burned. The new technology of unmanned aircraft vehicles (UAVs) is modified for use in agriculture. Images taken by satellite reveal information on the rate of photosynthesis of a given field. However, the pixel size in these images is frequently a square with 10 feet sides (Figure 3). With UAVs that fly no more than 100 feet over the fields, the pixel size is reduced to a few centimeters or the size of a leaf.[iv] UAVs not only provide more accurate information but also provide it on demand. Farmers are able to fly the UAVs without concern for cloud cover and when needed, not having to worry about positioning of satellites.
Another example of precision agriculture is the practice of zone management. A monoculture field is segmented into small sections (Figure 4). The planter, sprayer, and combine record measurements for each section. Each section is represented by the type of seed, other inputs, and finally the yield as measured by the combine. The level of an input, such as fertilizer, is adjusted as necessary to increase the yield of a low performing section.[v] This improves efficiency and minimizes waste of materials as only the necessary inputs are allocated to a section.
Precision agriculture is not only technically advanced machines or techniques. One practice that has become popular is the spreading of humus on farmland. Humus is organic matter, such as cover crops or silage, that cannot be broken down further (Figure 5). When spread across the field, it improves the soil structure, nutrient absorption, and water retention for the growing crops. Humus reduces and nearly removes the need for nitrogenous and phosphorous fertilizers, which adversely affect the environment when used in excess.[vi]
Why should we continue to practice current farming techniques? One impetus to continue with current farming methods is the loss of farm land. Over a 25 year period from 1982-2007, nearly 23 million acres of agricultural land was lost to development. The states of California and Florida were in the top three that lost the most farm land. The two states are responsible for half of the fruit and vegetables produced in the United States.[vii] Infrastructure for housing, businesses, or other needs is clearly taking precedent over farm land. With diminishing land devoted to growing the nation’s crops, the yield outputs will have to continue to rise if United States’ citizens want to continue to have the benefits from the current farming system.
One major indicator of the benefit of current farming practices is the percent of annual income spent on food. This percent for the United States (6.8) is the lowest in the world (Figure 6)[viii] Of course, socioeconomic factors are to consider in the statistics, but an argument can be made that food is relatively inexpensive and available in the United States. When was the last time you thought you would be unable to find food? Our farming practices have allowed for a surplus of food that has driven down the cost of food. As fewer people are required to work in the production of food, more people can work in other fields, such as software development or the service industry, to improve overall quality of life.
Farming techniques have developed significantly since the Great Depression to the modern day. Mechanized equipment, fertilizers, hybridized seeds, and other advancements allow for there to be a surplus in food. Precision agriculture requires a large capital investment that results in few people working in actual food production in the field. Is that a tradeoff we are willing to take? There is an argument for a return to traditional farming, without the inputs of fossil fuels in the form of fertilizers and mechanized equipment. Traditional farming is expensive and does not yield the same outputs as modern farming to adequately feed the population. It is simply unsustainable to return to traditional farming with the current population growth, unless you are willing for people to starve. Thus, there should be hope in the direction of precision agriculture for the world. It is important to remember that the agriculture process starts with the farmer. Farming is a lifelong profession. You rarely do it for a few years and then stop. The land is what allows the farmer to produce a crop to feed the world and provide a profit. The farmer has no incentive to destroy the land. The farmer protects his most valuable asset, which in turn provides for you.
[i] “Growing a Nation: The Story of American Agriculture.” Ag Classroom.
[ii] ”Green Revolution in Mexico and India.” Holt, Rinehart, and Winston.
[iii] Nielsen, R.L. Bob. “Historical corn grain yields for Indiana and the U.S.” Purdue University. August 2012.
[iv] “Precision Agriculture.” Louisiana State University. November 2009.
[v] Eory, Vera. ”Advice on the inclusion of precision farming in RPP2.” Climate X Change. March 2012.
[vi] “Practices that influence the amount of organic matter.” FAO.
[vii] “Farmland by the Numbers.” American Farmland Trust.
[viii] “Annual income spent on food.” Washington State.