by brita humphrey n.
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  1. By: Brita Humphrey corn

  2. History of Corn • Scientists believe that corn developed about 7000 years ago in the Tehuacan Valley of Mexico • Bred from a wild grass called teosinte • Small kernels that were spread out • Extinct today • Without human interference, corn could not have survived

  3. Ancient Mesoamerican Civilizations • Maya, Aztec, Toltec, Zapotec, Mixtec, and Olmec all relied on corn for most of their sustenance • Mayans are especially known for their reliance on corn • Gift from the gods, their sacred duty to cultivate it • Highly valued- jade was used to symbolize it • Ancient book of the Mayans, the PopolVuh, says that humans were made of corn; the gods had tried other materials, but failed • 70-80% of their diet consisted of corn

  4. North America • Corn spread from Mexico through extensive trade networks • Evidence that it was cultivated in the southwestern part of the United States about 3200 years ago, and by about 2100 years ago it made it to the eastern part of the United States • In 1492 there were about fifty thousand acres of corn being cultivated by Native Americans -most prominent in the semi-desert regions of what is today Arizona and New Mexico

  5. Hopi • Understood the art of dry-land farming, and they deeply respected the corn • Incorporated corn into their religion • A special ear of corn was dedicated to each Hopi child as a “Corn Mother” Hopi corn plot in a sand dune in Arizona ©

  6. Hohokam • Lived in the area of modern day Phoenix, Arizona • The ruins of their civilization are known as Pueblo Grande • Has the remains of an extensive system of canals used to irrigate crops • Took advantage of the natural slope of the land as well as the natural course of the river • Some of the canals were lined with clay to minimize the loss of water • The city of Phoenix is built on the ruins of 1,750 miles of ancient Hohokam canals • The settlers that moved to this area recognized that they were building their settlement out of the ashes of an old one; they therefore named their city Phoenix

  7. Across the Sea • 1492: Christopher Columbus landed in what is today Cuba • He observed the natives preparing corn, and shipped the new crop back to Spain • Corn was planted and spread quickly throughout Europe • Appealing to the lower class; it was less expensive than wheat, which was the other major grain at the time, and it also had a higher yield than wheat • By the early 1600’s, corn had spread to nearly every country in Europe

  8. Africa • Introduced to corn in the seventeenth century • Portuguese most likely introduced corn as a staple food for slaves • Old World cereals would not grow so close to the equator, and shipping flour by sea was too expensive to feed an entire slave population • Corn was relatively cheap and had a much higher yield than any of the Africans grains

  9. United States • 1800s : Corn was grown throughout the United States- therefore, it was rarely shipped across the country • 1828 : With the beginning of the railroad, shipping costs dropped significantly- made it profitable to ship corn • Shipping led to the specialization of the American economy • Northeast: industry • West: farming • Three-quarters of the area of the Corn Belt states (Illinois, Indiana, Iowa, Missouri, Minnesota, Ohio, and Wisconsin) is farmland, and this land accounts for 25 percent of the nation’s agricultural production

  10. Hybrid Corn • Majority of farms grow hybrid corn • “Hybrid vigor”- Charles Darwin • The first to discover that crossing unrelated varieties of plants produced hybrid vigor, and that the descendents of these hybrids did not have the same vigor • Convergence of two distinct corn lineages • William Beal • George Shull

  11. Danger • Hybrids, like the inbred varieties, are all genetically identical and are therefore subject to the same risks • Donald Jones states, “These genetically uniform pure line varieties are very productive and highly desirable when environmental conditions are favorable and the varieties are well protected from pests of all kinds. When these external factors are not favorable the results can be disastrous”

  12. Corn & Gender • In most Native American groups women were responsible for planting corn while the men hunted and fished • Women would make a hole in the soil with a stick, and then drop four to six kernels in it • They would sing to the spirits while performing this task, asking them to grant them a healthy crop • Mexican men were the ones to cultivate corn, but corn was also linked to women • Women spent up to a third of their waking lives making tortillas • An old Mexican proverb defined a good housewife as a woman who fed her husband and children well • Used corn tortillas as a way to express their feelings

  13. Nationality • Because corn was developed in central Mexico, it could be considered a national Mexican food • Most Americans tend to associate corn more with Native Americans, as we received corn from them- Thanksgiving • No link to nationality? • Corn has become completely incorporated into American society, and has spread throughout the world

  14. Class • When the Spanish conquistadors first colonized Mexico, they looked down on corn • They believed that wheat was the superior grain; Spanish missionaries even preached the goodness of wheat as a part of their attempt to convert the indigenous people to Catholicism • Thought that a person’s class, or caste, was reflected in their diet • In family portraits meant to catalog racially mixed castes, darker skinned people were always portrayed with native foods

  15. Corn Production • Over the years, corn has become an extremely prominent crop in the United States • United States produces a little more than 40 percent of the world’s corn

  16. Technology • Planter: machine pulled by a tractor, makes furrows in the soil that are three to four inches deep, and then disperses the seeds inside them • Furrows are thirty inches apart, and one planter can sow eight to sixteen rows at a time • Typical cornfield will have 16,000 to 32,000 corn stalks per acre • Central pivot: device that spins on wheels around a focal point, spraying water evenly over the cornfield • Chemical Fertilizers: replenish phosphorous and nitrogen in the soil

  17. Technology Planter Central Pivot

  18. Technology • Combine: contains a corn head, which cuts the stalk just above the ground • It can cut up to eight rows at a time • Once the stalks are cut, they are fed into the combine where the stalks, ears, and kernels are separated • The kernels are stored in a tank in the combine, and the remaining parts are dumped back on the ground • Grain elevator: Kernels have to be kept at 30◦F after they are dried to prevent mold from growing • Often owned by companies that buy corn from many different farmers; after cleaning it and storing it, they will sell it to refineries or food processors

  19. Technology Combine Grain Elevator

  20. Refinery • Wet milling: kernels are soaked in warm water, cooked, ground up by machines, then sent through a series of screens that separate the kernels into their parts (embryo, endosperm, and seed coat) • Used in the making of food and industrial products • Dry milling: kernels are ground into meal or flour • Sold to companies that make bread, cereal, or other such products

  21. Side Effects • A farmer’s profit is contingent on how much product he has, which makes it more profitable to produce more • More production drives the price of corn down, which means the farmer has to produce more to earn the same profit • This means they have to have more land for cultivation, which leads to an increase in farm size • The small farmers that cannot keep up are driven out of business • In 1988, research showed that even though the national acreage has held steady at 340 million acres, the average farm size has tripled while the total number of farms has been cut in half, from 5.9 million in 1945 to 2.2 million in 1985

  22. Political writer George Mills wrote,“The old definition of a farmer was a man with one hundred and sixty acres who kept some hogs and some cows and whose wife kept chickens and sold eggs and took their milk to the milk station. Now the average farmer in Warren County tills eight hundred acres because you can barely make a living on three hundred. The land hasn’t gone away but the farmer has.”

  23. Production Concerns • Environment • Health

  24. Environmental Concerns • Corn consumes a large amount of the nutrients in the soil • If the soil is not allowed to recover and the nutrients are not replenished, the soil will lose its fertility and dry out • According to the Department of Agriculture, one-quarter of all soil erosion in the United States can be attributed to corn alone • Application of chemical pesticides, herbicides, and fertilizers • Corn farming today consumes 44 percent of all chemical fertilizers in the United States and half of all farm pesticides and herbicides

  25. Health Concerns • Corn is being fed to livestock • Fattier meat- obesity crisis in the United States • In a 2010 study from the University of Melbourne, red meat that comes from corn-fed animals can be associated with an increased risk of mental health problems • Researchers also found that people in Australia (where the cattle are grass-fed) who ate more beef and lamb were less likely to have depression or anxiety • Chemicals • Can cause cancer and other diseases

  26. Why Hasn’t Production Changed? • In a 1986 Register editorial, Lauren Soth, a man whose editorials on corn politics over the last forty years won him a Pulitzer Prize, wrote “The hard fact that the USDA top command and the Fertilizer Institute cannot face is that agriculture in this country is substantially overexpanded. So is the agribusiness superstructure that serves it”

  27. Transnational Corporations • The history of Transnational Corporations goes back to the mentality of colonialism (especially European colonialism) • When colonizing a place such as Africa or the West Indies, they viewed the native ways as primitive and backward; the English way was much better, so they forced the natives to follow suit • The best summary of the colonialist attitude can be seen in a quote from British economist John Stuart Mill, who suggested that the colonized West Indies should not be seen as a country, but instead as a “place where England finds it convenient to carry on the production of sugar, coffee, and a few other tropical commodities”

  28. Transnational Corporations • Transnational Corporations also take this approach when dealing with American farms • Convenient places for them to make a profit • Focus on efficiency - push heavily for the use of technology and new innovations • Ex) Bt Corn: genetically engineered to produce a toxin against the corn borer • Companies such as Monsanto advertise this as being the “miracle” cure for the corn borer, and tell farmers that if they want their crop to be protected they need to buy Bt corn • Monocropping consequences, or Bt toxin problems

  29. Alternative: Organic • One of the key aspects of organic production is crop rotation • rotating corn with a legume, especially alfalfa, will replenish nitrogen in the soil • Using livestock manure is another way to replenish the nitrogen supply in the soil • The application of raw manure is forbidden within 90 days of harvesting when the corn is being harvested for human consumption, but this is typically not a problem because most field corn is grown for animal feed anyway • The most important thing to consider when applying manure is not to apply it in a way that could contaminate the water with bacteria or nitrates- Composting is a good idea

  30. Organic Pest Control • One option to avoid pests like the corn borer is to rotate the corn crop with a non-susceptible crop • Another option is to use biological controls- introduce natural pest predators into the cornfield • possible controls for the corn borer include the Ichneumonid, Braconid, and Trichogramma wasps, assassin bugs (right), damsel bugs, mantids, and spiders

  31. Organic Disease Management • Interestingly, the crop rotation practiced on organic farms along with proper fertility management seems to protect corn against disease quite effectively • Studies done in the late 1970s demonstrated that the Diplodia stalk rot was measurably less severe on organically managed corn fields in comparison to conventional production • Corn cam also be protected through selection • Organic and conventional farmers both tend to select varieties of corn based on regional performance, and so they often find that resistance or tolerance is bred into the corn itself • There are some new protection methods becoming available • Ex) fungus Trichodermaharzianum is now available and can be used to protect corn from infection by Pythium and Rhizoctonia species that cause seedling diseases

  32. Critics • Many people are under the misconception that organic agriculture cannot produce enough food to feed everyone • Mindset that large corporations and factory farms have been pushing • Experts: • Nobel Prize-winning plant breeder Norman Borlaug: “We aren’t going to feed 6 billion people with organic fertilizer. If we tried to do it, we would level most of our forest and many of those lands would be productive only for a short period of time.” • John Emsley, a chemist at Cambridge University: “The greatest catastrophe that the human race could face this century is not global warming but a global conversion to ‘organic farming’-an estimated 2 billion people would perish.”

  33. The Truth • Many agribusiness executives, agricultural and ecological scientists, and international agriculture experts believe that a large-scale shift to organic farming would not only increase the world’s food supply, but might be the only way to eradicate hunger

  34. The Truth • Variety of studies that were done around the world that show organic farms can produce as much or even more than conventional farms • Agricultural scientist Bill Liebhardt from the University of California-Davis studied 154 growing seasons’ worth of data on rain-fed and irrigated land in the United States, and found that organic corn yields were 94 percent of conventional yields • In the world’s poorer nations where hunger is the most prevalent, there is no yield gap between conventional and organic crops

  35. Is Change Viable? • The government gives subsidies based on the proportion of the amount of yield to total land area-therefore, farmers with higher yields and larger farms receive more benefits from the government, making it even harder for small farms to compete • Oversupply also encourages the processing of corn • Because corn is so cheap, companies can “add value” and create a new commodity for a higher price and profit • Farmers who use non-chemical methods for monitoring soil fertility and pest control by planting crops such as clover or alfalfa are not given government support for those crops

  36. Conclusion • Perhaps the best way to change corn production is to drastically reduce the consumption and production of corn • No more grain-fed meat • Large-scale monocrop production is in direct conflict with the idea of sustainable agriculture, which works together with the environment • Government policies • Give subsidies to farmers that successfully manage the water and soil without the use of chemicals • Farmers that do pollute the environment should be fined • Author Paul Faeth: “The challenge to agricultural policy-makers will be to create consistent incentives for all farmers to take up practices that are in line with what is most economical for society”