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READ: Crops that Grew the World

Humans have always moved plants around with us. But after 1500, a biological exchange between the Old and New Worlds changed global populations, trade networks, cultures, and environments.
The article below uses “Three Close Reads”. If you want to learn more about this strategy, click here.

First read: preview and skimming for gist

Before you read the article, you should skim it first. The skim should be very quick and give you the gist (general idea) of what the article is about. You should be looking at the title, author, headings, pictures, and opening sentences of paragraphs for the gist.

Second read: key ideas and understanding content

Now that you’ve skimmed the article, you should preview the questions you will be answering. These questions will help you get a better understanding of the concepts and arguments that are presented in the article. Keep in mind that when you read the article, it is a good idea to write down any vocab you see in the article that is unfamiliar to you.
By the end of the second close read, you should be able to answer the following questions:
  1. What’s the difference between staple crops and cash crops? What different effects did they have?
  2. How did European plantation owners maximize profits?
  3. In what ways did European colonists impact networks and production and distribution?
  4. How did European use of crops and animals affect the environment in the Americas?
  5. What effect did the introduction of the potato have on European populations? How did this change over time?

Third read: evaluating and corroborating

Finally, here are some questions that will help you focus on why this article matters and how it connects to other content you’ve studied.
At the end of the third read, you should be able to respond to this question:
  1. The author of this article argues that the “Columbian Exchange completely changed the face of the world.” Based on the evidence in this article, do you agree with this assessment? Why or why not?
Now that you know what to look for, it’s time to read! Remember to return to these questions once you’ve finished reading.

Crops that Grew the World

A painting of several women tending to the land. Their backs are bent over their work. The sky above them is dark and stormy.
By Bennett Sherry
Humans have always moved plants around with us. But after 1500, a biological exchange between the Old and New Worlds changed global populations, trade networks, cultures, and environments.

The long purée: Blending plants and cultures

Ever since humans began moving to new places, we've been bringing crops along with us. Ancient hunter-gatherers dropped seeds as they looked for new hunting grounds. From the eighth to thirteenth centuries, the Arab empires connected cultures from the Atlantic to the Indian Ocean in the "Islamic Green Revolution." This created a remarkable exchange network, spreading agricultural techniques. Crops like sugar, coffee, rice, and citrus fruits spread across their empire.
Global agriculture transformed again when Christopher Columbus stumbled upon the islands of the Bahamas in 1492. This connected the Eastern and Western Hemispheres for the first time in at least 10,000 years. History often focuses on the Spanish conquistadors who violently overthrew the Aztec and Inca Empires. But environmental historian Alfred Crosby has argued that the most important change brought about by the European conquests was not political. It was biological.
An image of a text that also features a drawing of a fruit-bearing tree.
Arab botanical treatise, twelfth century CE. Arab scholars pro- duced many such manuscripts on horticulture, animal husbandry, and irrigation. By Princeton University Library.
The story of plants is often lost in the story of colonization. Humans brought Afro-Eurasian plant species to the Americas, while American plant species were brought to Afro-Eurasia. Afro-Eurasia refers to the continents of Africa, Europe, and Asia. American plants became staple crops, or the most important foods, across Afro-Eurasia, transforming agriculture from Ireland to China. This exchange of crops between the Americas and Afro-Eurasia, also known as the "Columbian Exchange," reshaped the size, health, and wealth of global populations.

The spud that could: Potatoes and populations

Why was the Columbian Exchange so important? Let's start with the potato. Native to Peru, the potato provided Western and Northern Europe with a new source of calories, feeding European people and the armies that extended European empires into Africa and Asia.
Crops from the Americas saved millions of people in Afro-Eurasia from starvation. The extra nutrition provided by potatoes, maize (corn), and other American crops caused the world's population to rise after 1500. That's despite the millions of indigenous Americans who died from European disease and violence as a result of the Columbian Exchange.
How did potatoes and other crops do this? Potatoes are rich in nutrition and can be grown in places that are too dry for rice or too wet for wheat.
A painted portrait of a man. He is sitting at a desk, writing with a quill and ink, and holding a bouquet of flowers and corn in his other hand.
A portrait of the French scholar, Antoine Parmentier, who made it his life’s work to promote the potato from a food for pigs and livestock to a national staple. Pictured here holding crops from the Americas, including maize and the potato flower. His grave in Paris is surrounded by potato plants, and admirers still place potatoes on his tombstone. By François Dumont, public domain.
OK, the potato is pretty boring food. We love french fries, but when people in Europe and China first saw this misshapen brown lump that grew under the dirt, they didn't think it looked tasty. But rulers discovered that a field of potatoes could feed three times as many people as a field of wheat. After that, European governments encouraged farmers to grow potatoes. By the beginning of the nineteenth century, potatoes were a staple in Northern Europe. In Qing dynasty China, potatoes were used to feed armies and settlers, helping the Chinese empire to nearly triple in size.
Map shows the expansion of the Qing empire, which eventually covered an extremely large region.

Growing money: Cash crops, plantations, and global trade networks

We call potatoes and maize staple crops because they were a main food source that helped to increase global populations. But another type of crop also transformed the global economic system. These were known as cash crops.
Unlike staple crops, cash crops are grown to be sold for as much profit as possible. Europeans brought plants from Asia, such as sugar and coffee, to grow as cash crops in the Americas. They also turned American plants, like tobacco and cacao, into cash crops. European colonists learned that the best way to make a profit was to farm huge numbers of the same species of plant, also called monoculture. Then, the plantation systems forced enslaved people to farm vast fields of monoculture cash crops.
Cash crops and plantations were profitable because Europeans established global trading networks. European merchants sold American-grown cash crops in Asian and European markets at a huge profit. Often, they brought along new crops like potatoes and maize. This sped up the transfer of new foods and cultural tastes around the world.

Talking turkey: Biological exchange and cultural integration

The Columbian Exchange forever changed cultures around the world, especially in the kitchen. Try to imagine Italian food without tomatoes, or Indian food without chili peppers. Since 1500, the world's diet has been significantly shaped by the Columbian Exchange. People quickly made new foods a part of their culture, and soon it seemed like those foods were always there. To see just how quickly the Columbian Exchange changed culture and language, let's talk turkey.
In the English language, there's a bird known as the turkey. The English use the name turkey because the British thought the bird was from Türkiye, or the land the British called Turkey. But the Turks called the bird hindi because they thought it came from India. The Dutch also believed the bird came from India. So where did the bird come from?
None of these places–the turkey is actually from Mexico. The English and Dutch assumed the birds were Turkish because they bought them from Turkish and Indian merchants. In reality, those merchants had bought the birds from Spanish merchants, who brought the birds from Spanish colonies in Mexico. People did not always explain where food came from back then.
This misunderstanding about one bird symbolizes the rapid and widespread changes brought by the exchange. When a new species was introduced to Afro-Eurasia, it took only a few decades before most people assumed it had always been there.

Disaster: Community and environmental disruptions

In this system of biological exchange, the Americas gave and Afro-Eurasia took. Staple crops from the Americas helped grow Afro-Eurasian empires, while cash crops made fortunes for European colonizers.
Photo taken from afar shows extremely large piles of bright red chile peppers. From a distance, the peppers look like large patches of red dirt.
Chili peppers, which are native to Mexico, drying in the sun in Grandhasiri Village, Guntur district, India. By Adityamadhav83, CC BY-SA 3.0.
The crops that Europeans brought to the Americas devastated local ecosystems and cultural practices. European animals, especially cattle, destroyed indigenous plants. The Spanish replaced indigenous, or native, crops with wheat, barley, and sorghum. European plantation owners destroyed the food and habitats of indigenous animals to make farmland.
The Columbian Exchange wasn't all good news for Afro-Eurasia. Many European populations came to depend on the potato. Monoculture crops can get diseases too, and one disease could wipe out the food source for millions. Perhaps the most famous example is the Irish Famine of 1845 when millions of Irish starved after a plant disease destroyed the potato crop.


The global biological exchange that started in 1492 continues today. The networks and technology that let us travel faster and farther than ever before continue to bring new plants to new places, often with harmful effects on indigenous species. Of course, we also benefit from these exchanges. Go to the nearest grocery store, and you're certain to find food made from plants that started on a different continent.
Sculpted figures in a stone courtyard. The sculptures are devastatingly thin and carry pained expressions on their faces.
The Famine Memorial sculpture in Dublin, Ireland. By William Murphy, CC BY-SA 2.0.
Author bio
Bennett Sherry holds a PhD in history from the University of Pittsburgh and has undergraduate teaching experience in world history, human rights, and the Middle East at the University of Pittsburgh and the University of Maine at Augusta. Additionally, he is a research associate at Pitt's World History Center. Bennett writes about refugees and international organizations in the twentieth century.

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