HIST 480: CAPSTONE SEMINAR

FINAL PAPER

INTERESTING FINDINGS ON THE USE OF SWEET POTATO AND MAIZE IN CHINA: A STUDY OF THE ONGOING IMPACT OF THE COLUMBIAN

EXCHANGE

MAX GOLDMAN

4/29/2015

Given an ever-expanding understanding of the specious present, historians have

sought to explain the origins and historical development of the globalized world of today

through new lenses. Such an approach seems to have been adopted by the likes of Alfred

W. Crosby and Charles Mann, historians who were instrumental in fostering in students

of history radical new ideas regarding the beginnings of the world we are so familiar with

today. In their narratives, these historians have attempted to argue that European contact

with the New World produced a chain reaction leading to 1) the deaths of millions of

Natives, the ecological devastation of American environments by European animals

along with the Old World reaping the fruits of the Americas leading to the former’s

population growth, 2) Europe’s ecological and biological conquest of Neo Europes in the

Americas and in Oceania and 3) the origins of global ecological, biological and cultural

homogenization. What these trios of historians do not illustrate sufficiently is the role of

the Columbian Exchange- specifically the introduction of the sweet potato and maize- on

20th century China.

As an aspiring historian of China and East Asia, I was initially drawn to the

methodology employed by historians Dennis Flynn and Arturo Giraldez. Though focused

on the silver, I found this following statement to be of critical importance in describing

the important role of China, be it in a “Columbian Exchange” or otherwise.

We intentionally emphasize the role of China and its tributary system… because the scholarly literature in general has neglected this pivotal country, certainly in recognizing China as a prime causal actor.1

According to J.S. Cooley, the sweet potato’s origins are shrouded in mystery.

Specifically, he notes, “no single wild species has been found that is definitely known to

be the plant from which the sweet potato derives.”2 Cooley further comments that the

plant is not known to be native to any regions other than tropical America and its islands.3

However, Cooley also points out that prior to European contact, sweet potatoes served an

important function not only for the peoples of “tropical America but also for the Maori of

New Zealand, leading some anthropologists to theorize that the crop originated in New

Zealand.”4 Andrew Lawler would support this claim, and argues that as masters of the

sea, Polynesians were able to establish permanent biological contact with South America,

and thus were able to introduce sweet potatoes to Oceania.5 Alfred W. Crosby would also

point out that “sweet potatoes along with white potatoes allowed the Maoris to gain the

means to produce large quantities of food” and enter into a European created world

market.” 6

1 Dennis Flynn and Arturo Giraldez, “Born with a Silver Spoon: The Origin of World Trade n 1571”, Journal of World History, Vol.6, No. 2 (1995), 201-219, 202.

2 J.S. Cooley,” The Sweet Potato: Its Origins and Primitive Storage Practices”,Economic Botany, Vol.5, No.4. (1951), 378-386, 379.

3 Ibid., Also significant is that early historical literature documenting the “sweet potato” does not clearly distinguish between the yam or the sweet potato.

4 Ibid., 381.5 Andrew Lawler, “ Beyond Kon Tiki: Did Polynesians Sail to South America?”. AAAS, Vol. 328, No, 5984 (June 2010), 1344-1347: 1345.

6 Alfred W. Crosby, Ecological Imperialism: The Biological Expansion of Europe, 900-1900, new Ed( New York, NY: Cambridge University Press, 2004), 230. I conclude that Crosby would point out that New Zealand’s climate and soils were “nearly ideal”. Such is likely to be a major factor in the success of sweet potatoes in New Zealand.

In his book The Columbian Exchange, Crosby provides an empirical illustration

of the historical significance of the sweet potato crop to the Old World, along with

several others. In a chart titled “Varieties of Old and New World Staples” (in millions of

calories per hectare.”7 The chart indicates that sweet potatoes, along with maize, potatoes

and manioc produced higher caloric yields than Old World crops, with sweet potatoes

and maize producing 7.1 and 7.3 million calories per hectare, higher than the “chief Old

World Crops” rice and wheat, which yielded 7.3 and 4.2 million calories per hectare.8 In

support of these findings, historian Andre Gunder-Frank remarks that sweet potatoes,

along with maize, squash and beans” radically increased the cropping possibilities and

chances of survival in Europe and China,” since American crops were better adapted for

growing in harsher climates.9

Sweet potato cultivation, as noted by Gunder-Frank was first undertaken in China

during the 1560’s.10 But how did the sweet potatoes arrive in China? During the Ming

Dynasty, there lived certain Chen Zhenlong- an enigmatic figure. According to Historians

Charles Mann and Christopher Cumo, Chen served as a human agent of the Columbian

Exchange in China. Specifically, Mann points out Chen’s contribution in making China

the “world’s biggest sweet potato grower, producing more than three quarters of the

global harvest.”11 A merchant in the Fujian city of Yuegang,12 he first encountered the

7 Alfred. W Crosby, The Columbian Exchange: Biological and Cultural Consequences of 1492 (Westport, CT: Greenwood Publishing Group. Inc, 2003), 175. 8 Ibid.9 Andre Gunder-Frank, ReOrient:Global Economy in the Asian Age ( United States: University of California Press, 1998), 60.

10 Ibid.11 Charles Mann, 1493: Uncovering the New World Columbus Created ( Toronto, Canada: Random House of Canada, 2011), 167-168.

12 Fujian and Yuegang had been China’s “centers of maritime trade”. During the “Age of Sail”, this meant that both were centers of international trade. Also interesting to note is that Fujian province was “the worst affected by piracy” and was also chronically at rise of famines.

sweet potato during the 1590’s while visiting Manila. A shrewd businessman, Zhen

decided to bribe “the barbarians (probably a reference to the Spanish or the Portuguese)

to acquire segments of the vine.” 13 A similar narrative is told by Christopher Cumo, but

differs slightly from Mann’s version with the additional detail that “ the story leaves

unclear how and when the Philippines received the Sweet potato, if Portugal did not plant

it until 1600”.14 Both Mann and Cumo agree that the actual date of introduction of the

sweet potato is unknown, as Fujian merchants kept this information secret.15 However,

Mann suggests that the account of the sweet potato’s introduction into China comes from

a narrative composed by a descendant who wrote the True Account of the Story of

Planting Sweet Potatoes in Qinghai, Henan and Other Provinces an essay detailing how

the crop should be planted. 16 Another interesting hypothesis connects decisions made by

China’s historical bureaucratic leadership positive economic growth in China vis a vis the

cultivation of New World crops.17 According to Angus Madison,

the economic impact of the Chinese bureaucracy was very positive for agriculture…the bureaucracy promoted the introduction of new world crops such as maize, potatoes, sweet potatoes, peanuts and tobacco in the Ming.

Did the introduction of the sweet potato yield any tangible outcome? According to

Ruixue Jie, who relates climate change, sweet potatoes and peasant revolts, argues that

prior to the introduction of the crop, “exceptional droughts increased the probability of

13 Ibid., 168.14 Christopher Cumo, The Ongoing Columbian Exchange: Stories of Biological and Economic Transfer( United States of America: ABC Clio, 2015), 293.

15 Mann, 1493, 168. Ibid., 293. 16 Ibid.,17 Angus Madison, “China in the World Economy: 1300-2030”,International Journal of Business, Vol 11. No. 3( 2006), 239-254, 240-241. Madison also praises the historical Chinese bureaucracy by noting that it has helped improve agricultural yields, developed printing, and settled farmers in new regions. However, he also points out that Chinese bureaucrats considered agriculture the most significant sector “from which they could squeeze a surplus in the form of taxes and compulsory levies”.

peasant revolts by approximately 0.7 percent, while after the arrival of sweet potatoes,

droughts only increased the likelihood of peasant uprisings by 0.2 percent.”18

Further, it is important to note that since its Chan’s introduction of the crop into

China in the 16th century, one must take into consideration an argument made by

Jennifer Woolfe in her book Sweet Potato: An Untapped Resource. Woolfe describes

China as “ an excellent example of a country which has diversified into many products,

illustrating the versatility of sweet potatoes as a raw material for industrial and food

processing.”19 Historian Jonathan D. Spence would point out that in Modern China, the

sweet potato was a food associated with the peasantry.20 He points out that for farmers in

Shandong Province during the 1930’s, sweet potatoes rather than millet represented an

important crop for the world they lived in.21 Specifically, Spence notes that the poor in

Shandong consumed sweet potatoes at every meal, “every day throughout the year,”and

describes the variety of uses of the sweet potato in local cuisine

From harvest time until the spring of the following year, farmers eat fresh sweet potatoes; when these are gone, they eat the stored dried slices; these are boiled, ground into a meal that is mixed with other flour to make bread or noodles22

18 Ruixue Jia, “ Weather Shocks, Sweet Potatoes and Peasant Revolts in Historical China”, The Economic Journal, Vol. 124, Issue 575 ( 2013), 92-118, 92. Jia also comments that “Weather shocks” are often considered to increase the likelihood of civil unrest due to associated “negative income shocks”. However, Jia point out that this connection cannot be decisively confirmed as Jia lacks “systematic output data for historical China”.19 Jennfier A. Woolfe, Sweet Potato: An Untapped Resource (Victoria, Australia: Cambridge University Press, 1992), 288.

20 Jonathan D. Spence, The Search for Modern China (United States of America: W.W Norton&Company, 1990), 432. In an interesting contrast with Jia, Spence does not seem to mention whether peasants revolts were still linked to sweet potatoes, or he might have lacked records detailing a connection.

21 Ibid.22 Ibid. Spence suggests that such a monotonous diet was an “indelible part of the rural poor’s existence.

Woolfe provides a supplementary account of the sweet potato to Spence’s, and statesthat

the “sweet potato was no doubt an important staple food for most Chinese people until

1949”.23 Specifically, she provides a table indicating “Total Area Devoted to Sweet

Potato Growing in China, 1946-88.” From the table, one can infer that sweet potato

cultivation has been experiencing steady increases since 1946, but these figures decline

gradually from the 1980’s onwards.24 For example, sweet potato cultivation area

achieved a high of 9.6 million hectares in 1963 – and began to slowly decline in the

1970’s leading to a cultivation of only 6.9 million hectares in 1982, and 6.5 million by

1985.25 Another fact worth noting- earlier, I noted that Spence tells us that for rural

farmers in Shandong province, sweet potatoes served as the basis for a rather

monotonous diet. On that note, Woolfe notes that in Shandong Province sweet potato

production is described as “insufficient but profitable.”26 Yet despite this, the area for

sweet potato cultivation there continues to decline.27

Another New World crop that impacted China in a significant way was American

maize. Much like that of the sweet potato, the exact date when maize was first cultivated

remains unknown.28 Specifically, James McCann notes that although it is unclear when

the crop was first grown, by 1500 AD the Aztec and Mayans civilizations begun calling

the plant descended from a “single unknown ancestor” maize- which meant that which

23 Woolfe, Sweet Potato: An Untapped Food Resource, 488.24 Ibid. 25 Ibid., Woolfe points out that although sweet potatoes continued to play an important role in subsistence agriculture, its function began to radically change after the 1970’s as a result of a government initiative to increase wheat and rice production.

26 Ibid., 492.27 Ibid.28 James McCann, “Maize and Grace: History, Corn, and Africa’s New Landscapes, 1500-1999”, Comparative Studies in Society and History, Vol. 43, No. 2(2001), 246-272, 248.

sustains life.29 McCann also states that maize, like sweet potatoes serve as a major raw

material, as “agribusiness uses its starches for and cellulose for fuel, food, fodder, paint

and penicillin.30” Though McCann suggests that maize evolved from a mysterious

ancestor, Mary Eubanks would argue that scientists have discovered evidence linking

maize to “teosinte”- a “closely related wild grass endemic to Mexico where maize is

believed to have originated.”31 Further, Eubanks exclaims that a great mystery in botany

lies in how teosinte was able to radically transform into a “structure that is unparalleled

anywhere in the plant kingdom, the highly prolific ear that produces hundreds of

kernels.”32

Many theories circulate around when maize was actually introduced into China.

Some historians, such as Joseph Needham provide varying accounts detailing the origins

of maize in China. One suggests that maize had been known in China since

approximately 1570 as “tribute wheat”, “jade wheat”, “jade grain “or “wrapped

grain.’’33 It was also referred as “barbarian wheat” since it came to China from the West,

but other hypotheses postulated that maize arrived in China from India and Burma, yet

other accounts suggest an even earlier date of introduction- 1511- arguing that maize

must have arrived from coastal regions.34 Still others have cited Spanish historical

documents, stating that “enormous quantities of maize were paid as tax grain in the late

29 Ibid. 30 Mary W. Eubanks, “The Mysterious Origin of Maize”, Economic Botany, Vol.55 No. 4 (2001), 492-514, 494.31 Ibid.32 Ibid. Eubanks does note that one possible reason for the mystery of the aforementioned “radical transformation” is progressive evolution, during which time “mutations accumulated over a long period”. 33 Joseph Needham, Science and Civilization in China:Volume 5, Chemistry and Chemical Technology, Part 2, Spagyrical Discovery and Invention: Magisteries of Gold and Immortality (Cambridge, UK: Cambridge University Press, 1984), 455. 34 Ibid.

16th century” which might refer to a Spanish origin for Chinese maize.35 However,

Zheng Yangwen suggests a more concrete origin to maize cultivation in China and notes

that it arrived several decades prior to 1550, prior to yams, which were introduced in

1594.36 Maize was initially introduced into the coastal provinces of Jiangsu, Zhejiang

and Fujian37(interestingly, Fujian was also the site where Zhenlong Chen, the merchant

who introduced sweet potatoes into China, hailed from and is likely also where sweet

potatoes first entered China). Thus when maize was introduced into China, it was

discovered that a major advantage that crop had was that it was capable of growing in

differing climates, specifically “ cold, hot, dry, or wet climates- even on mountains,

valleys or plains.” 38 E.N. Anderson would support this claim and remarks that during

the Ming Dynasty, maize began a massive regional proliferation as the crop “took over

vast stretches of the West and South and began to encroach everywhere.”39 Rebecca

Earle, who suggests that maize, like the sweet potato was a crop more highly valued by

peasants than elites, supports this claim. Specifically, she claims “peasants embraced

these new foods because they required less labor than rice to cultivate.”40 It would seem

that maize was generally a successful crop in urban regions during the 1970’s and

35 Ibid. 36 Yangwen Zhen, China on the Seas: How the Maritime World Shaped Modern China (Leiden, Netherlands: BRILL, 2011), 120. 37 Ibid. 38 Ibid., 124-125. It is interesting to note that while Chinese peasants dedicated the most fertile lands to cultivating rice, they utilized the sides of mountains and valleys to cultivate maize. 39 E.N. Anderson, The Food of China ( United States of America: Yale University Press, 1988), 115. Anderson also relates the presence of maize and the occurrence of rebellions in the South and South West of China. Specifically, he argues that such a connection exists because the presence of maize allowed for increases in population.40 Rebecca Earle, “ The Columbian Exchange” in The Oxford Handbook of Food History ed. Jeffrey M. Pilcher (New York, NY: Oxford University Press, 2012), 351.

1980’s.41 In fact, maize quickly became a crucial ingredient in many local seasonal

cuisines. In one case( in the city of Shenyang), during the spring 15% of families

claimed that they consumed corn at 5% of their meals,42 while a study conducted in the

fall in Kangping County showed a high incidence of maize consumption where 50% of

families consumed it at 17% of their meals.43 These figures are significant not only

illustrating the significance of the crop in allowing the people of Shenyang and

Kangping County to have a more diversified pallet, but these statistics also provide

evidence supporting the notion that maize was a resilient crop, capable of producing

enough in multiple seasons. In comparing maize to rice, Leppman points out that maize

“requires less water but produces more calories per unit of land.”44

Historically, maize was not only of use to China urban dwellers, for it also had

major impacts on the environment. Specifically, historian Robert B. Marks states

that because general New World crops were available, certain ethnic minorities in

China were able to migrate “throughout the mountainous areas of the south of

China.”45 One such group was the Hakka peoples. Marks notes that in order for the

Hakka to plant maize, they had to cut down “upland forest to open fields.”46 Further,

because maize was a “heavy feeder,” it was able to rapidly decrease the fertility of

upland soils in which it was grown within 2 years.47 In support of this evidence,

41 Elizabeth J. Leppman, Changing Rice Bowl: Economic Development and Diet in China (Hong Kong: Hong Kong University Press, 2005), 133.

42 Ibid., 133.43 Ibid.44 Ibid., 135.45 Robert B. Marks, China: Its Environment and History (Lanham, MD: Rowman& Littlefield Publishers, 2012), 206. Marks also notes that because “hungry crops depleted the soil, soil naturally returned to a state of infertility, lack of humus, acidity, podsolization or latosolization”.46 Ibid.47 Ibid., 214.

Evelyn S. Rawski states that maize supplanted millet as the major “autumn crop” in

some places. Quoting Yen Ju-I, Rawski notes that although mountains harvests in

the fall largely yielded millet, maize yielded more profit.48 Further, Rawski points

out that for those who settled on “marginal lands,” maize became a dominant

staple.49 According to an 18th century gazetteer, who commented on the significance

of the crop to settlers on marginal lands,” what the peasants rely on for food is

barley, buckwheat, millet and primarily, maize.”50 After having several successful

harvests, mountain peasants began relying solely on this crop for food.

In a table provided by Ashtok Gulati, John Dixon, and John Mezies Dixon titled

“ Sown Area and Production of China’s Maize Economy and its Place in the World,

1970-2000”, one can infer that from the 1970’s until the present, the amount of land

dedicated to cultivating maize, along with maize production, has steadily increased.51

Specifically, the editors point out that in 1970, maize cultivation represented 17

percent of China’s arable area, while also making up 16.9 percent of agricultural

production.52 These figures increase gradually- by the end of the twentieth century

and the beginning of the 21st century, maize cultivation in China took up between 23

and 27 percent of China’s agriculturally useful land area, representing

approximately 25 to 26 percent of China’s agricultural production.53 Another

intriguing statistic is also given- “China’s maize in World Maize Economy.” By

48 Evelyn S. Rawski, “Agricultural Development in the Han River Highlands”, Ching-shih wen t’i, Vol. 3 , No.4 (`1975), 63-81, 68. 49 Ibid.50 Ibid.51 Ashok Gulati, John Dixon and John Mezies, eds., Maize in Asia: Changing Markets and Incentives( New Delhi, India: Academic Foundation, 2008), 97.52 Ibid.53 Ibid.

2000, the area of maize cultivation levels in China was 16.6 percent of global levels,

while Chinese production of the crop represented 18 percent of world totals. 54 As of

2010, maize has become China’s “third most important grain, and China has become

the world’s second largest producer of it.”55 Perhaps one the most significant new

uses of maize are in the production of ethanol, in response to rising oil prices and the

search for “cleaner energy sources to combat global warming.”56 These facts and

statistics would no doubt impress the 3rd to 10th century CE Zapotec and Moche

native Americans of Central Mexico, who would likely marvel at how the crop they

once worshipped by “displaying it on ceremonial ancestral figures in the Zapotec

pantheon associated with growing maize”57, has not only served as a staple crop for

the mountain dwelling peasantry of a faraway land but also as one of that same

land’s most important grains.

Ultimately, it can be inferred that though some of the commodities of the

Columbian Exchange have impacted China’s population in profound ways, in none of the

sources I explored did I find a relationship between the cultivation and consumption of

sweet potatoes and maize in 20th century China and China’s population growth, a

hypothesis I had originally intended to formulate. What can be known to historians,

however, are the following: both the sweet potato and maize served as crops that helped

54 Ibid. Gulati, Dixon and Mezies point out that “currently, maize is grown in every province in China”, although major differences exist between the types of maize grown and cropping patterns.” Further, much of China’s maize in grown in the Northeast and Northwest, regions with a temperate climate.55 Ibid.56 Jennifer Huang McBeath, Jerry McBeath, Environmental Change and Food Security in China( Dordrecht, Heidelberg, London, New York: Springer, 2010), 35. The authors also point out a controversial fact regarding the 21st century usage of maize in China- specifically, the authors note that “most corn is used as animal feed”. 57 Eubanks, “Mysterious Origin of Maize”, 493.

diversify the diets of China’s poor. Though we may never know for sure the exact role of

individual agents of the Columbian Exchange such as the Ming Dynasty Fujian merchant

Chen Zhenlong in introducing the sweet potato into China nor the true means by which

maize first was introduced there, fortunately, tangible, empirical evidence abounds

detailing the impact of these crops on China’s population. As Spence points out , during

the first half of the 20th century, the sweet potato proved to be a reliable staple for the

rural poor in Shandong Province, and experienced a period of rapid increase in

cultivation area, but declined after the after the 1970’s. Even more interesting is the

proposed link between droughts, sweet potatoes and uprisings in China, as Jie remarks

that the introductions of sweet potatoes, “droughts increased the probability of peasant

movements slightly.” 58Evidence suggests that maize impacted China in equally profound

ways-for example, maize allowed urban Chinese resident to enjoy a wider array of foods,

quickly becoming a crucial ingredient in many local cuisines. Kangping County

demonstrated a high incidence of maize consumption where at least half of families there

consumed maize in some form at their meals. Maize however did impact China in more

observable ways as well. When planted by the Shack people in mountainous regions,

maize- what Marks describes as a “heavy feeder”, was capable of causing soils to become

unfertile. 59However in another example, almost ironically, this “heavy feeder” has also

found a new role as a clean source of energy.60 Thus, the findings that have been

presented are significant in supporting the notion that the Columbian Exchange and its

associated commodities continue to significantly affect regions of the world today-in this

case, one can infer that though sweet potato cultivation rates have likely declined,( as I

58 Jia, “ Weather Shocks, Sweet Potatoes and Peasant Revolts”, 92. 59 Marks, China: Its Environment and History, 214.60 McBeath and McBeath, Environmental Change and Food Security, 35.

have already illustrated), other commodities such as maize continue to be a major

agricultural staple in China and may continue to benefit China and the world as an

alternative energy source in years to come.

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