Three Sisters (agriculture)

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Maize, climbing beans, and winter squash planted together Three Sisters companion planting technique.jpg
Maize, climbing beans, and winter squash planted together

The Three Sisters (Spanish : tres hermanas) are the three main agricultural crops of various indigenous peoples of Central and North America: squash, maize ("corn"), and climbing beans (typically tepary beans or common beans). In a technique known as companion planting, the maize and beans are often planted together in mounds formed by hilling soil around the base of the plants each year; squash is typically planted between the mounds. The cornstalk serves as a trellis for climbing beans, the beans fix nitrogen in their root nodules and stabilize the maize in high winds, and the wide leaves of the squash plant shade the ground, keeping the soil moist and helping prevent the establishment of weeds.


Indigenous peoples throughout North America cultivated different varieties of the Three Sisters, adapted to varying local environments. The individual crops and their use in polyculture originated in Mesoamerica, where squash was domesticated first, followed by maize and then beans, over a period of 5,000–6,500 years. European records from the sixteenth century describe highly productive Indigenous agriculture based on cultivation of the Three Sisters throughout what are now the Eastern United States and Canada, where the crops were used for both food and trade. Geographer Carl O. Sauer described the Three Sisters as "a symbiotic plant complex of North and Central America without an equal elsewhere".

Cultivation methods

The Three Sisters planting method is featured on the reverse of the 2009 US Sacagawea dollar. 2009NativeAmericanRev.jpg
The Three Sisters planting method is featured on the reverse of the 2009 US Sacagawea dollar.

Agricultural history in the Americas differed from the Old World in that the Americas lacked large-seeded, easily domesticated grains (such as wheat and barley) and large domesticated animals that could be used for agricultural labor. At the time of first contact between the Europeans and the Americans, Carlos Sempat Assadourian writes that Europeans practiced "extensive agriculture, based on the plough and draught animals" while the Indigenous peoples of the Americas practiced "intensive agriculture, based on human labour". [2]

In Indigenous American companion planting, maize (Zea mays), beans (wild beans and vetches [3] spp.), and squash ( Cucurbita pepo ) are planted close together. The maize and beans are often planted together in mounds formed by hilling soil around the base of the plants each year; squash is typically planted between the mounds. [4] In the northeastern U.S., this practice increases soil temperature in the mound and improves drainage, both of which benefit maize planted in spring. [4] In Haudenosaunee or Iroquois farming, the fields were not tilled, enhancing soil fertility and the sustainability of the cropping system by limiting soil erosion and oxidation of soil organic matter. [5] A modern experiment found that the Haudenosaunee Three Sisters polyculture provided both more energy and more protein than any local monoculture. [5]

The three crops benefit by being grown together. [4] [3] The cornstalk serves as a trellis for the beans to climb, the beans fix nitrogen in the soil, and their twining vines stabilize the maize in high winds, and the wide leaves of the squash plant shade the ground, keeping the soil moist and helping prevent the establishment of weeds. [6] [7] The prickly hairs of some squash varieties deter pests, such as deer and raccoons. [7]

Although this synergy had been traditionally reputed among American cultures, scientific confirmation has arrived only much more recently. [3] Much of this research was performed in the Soviet Union in the early 1970s and published in several volumes of Biochemical and Physiological Bases for Plant Interactions in Phytocenosis edited by Andrey Mikhailovich Grodzinsky  [ uk; ru ]. [3] Dzubenko & Petrenko 1971, Lykhvar & Nazarova 1970 and Pronin et al. 1970 find a wide number of leguminous crops increase the growth and yield of maize, while Gulyaev et al. 1970 select later maturing lines of beans to produce the converse effect, increasing even further the yield gain of beans when planted with maize. [3] Pronin et al. 1972 find increased productivity and root exudate in both crops when combining faba beans with maize, and even more so in soils with preexisting high nitrogen fixing microorganism activity. [3]

Three Sisters mound planting in Arizona, 2022 Three Sisters mound culture in Arizona Mountains.jpg
Three Sisters mound planting in Arizona, 2022

Indigenous peoples throughout North America cultivated different varieties of the Three Sisters, adapted to varying local environments. [8] The milpas of Mesoamerica are farms or gardens that employ companion planting on a larger scale. [9] The Ancestral Puebloans adopted this garden design in the drier deserts and xeric shrublands environment. The Tewa and other peoples of the North American Southwest often included a "fourth Sister", the Rocky Mountain beeplant, which attracts bees to help pollinate the beans and squash. [10] The Three Sisters crop model was widely used by a number of First Nations in the Great Lakes–St. Lawrence Lowlands region. [11]


European records from the sixteenth century describe highly productive Indigenous agriculture based on cultivation of the Three Sisters throughout what are now the Eastern United States and Canada, from Florida to Ontario. [5] The geographer Carl O. Sauer described the Three Sisters as "a symbiotic plant complex of North and Central America without an equal elsewhere". [12] The agronomist Jane Mt. Pleasant writes that the Three Sisters mound system "enhances the soil physical and biochemical environment, minimizes soil erosion, improves soil tilth, manages plant population and spacing, provides for plant nutrients in appropriate quantities, and at the time needed, and controls weeds". [4] After several thousand years of selective breeding, the hemisphere's most important crop, maize, was more productive than Old World grain crops. Maize produced two and one-half times more calories per given land area than wheat and barley. [13]

Nutritionally, maize, beans, and squash contain all nine essential amino acids. [5] The protein from maize is further enhanced by protein contributions from beans and pumpkin seeds, while pumpkin flesh provides large amounts of vitamin A; with the Three Sisters, farmers harvest about the same amount of energy as from maize monoculture, but get more protein yield from the inter-planted bean and pumpkin. Mt. Pleasant writes that this largely explains the value of the Three Sisters over monoculture cropping, as the system yields large amounts of energy, and at the same time increases protein yields; this polyculture cropping system yielded more food and supported more people per hectare compared to monocultures of the individual crops or mixtures of monocultures. [5]


Scholars Mt. Pleasant and Burt reproduced Iroquois methods of cultivation with Iroquoian varieties of maize at several locations in New York. They reported maize yields of 22 to 76 bushels per acre (1.4 to 4.8 tonnes per hectare). Soil fertility and weather were the main determinants of yield. [14] Mt. Pleasant also questioned the conventional wisdom that the Iroquois practiced slash-and-burn agriculture, abandoning fields when the soil was depleted of nutrients after several years of farming, but instead claimed that Iroquoian no-till farming techniques preserved soil fertility. [15] In a similar experiment to reproduce Native American agricultural practices in Minnesota, Munson-Scullin and Scullin reported that over three years, the per-acre annual maize yields declined from 40 to 30 to 25 bushels (2.5, 1.9, and 1.6 t/ha). [16]

Other scholars have estimated lower average yields of maize. Hart and Feranec estimated the yield of Huron agriculture at 8 to 22 bushels per acre (0.5 to 1.4 t/ha), the higher yields coming from newly cultivated land. The Huron lived in Ontario near the northern limit of where agriculture was feasible and had less fertile soils than many other regions. Nevertheless, they produced surpluses for trading with nearby non-agricultural peoples. [17] Bruce Trigger estimates that the Hurons required .4 to .8 acres (1,600 to 3,200 m2) of land under cultivation per capita for their subsistence with more cultivated land required for trade. [18] Sissel Schroeder estimates that the average yield of Native American farms in the 19th century was 18.9 bushels per acre (1.2 t/ha), but opines that pre-historic yields might have been as low as 10 bushels per acre (0.6 t/ha). [19] As the Iroquois and other Native Americans did not plow their land, Mt. Pleasant and Burt concluded that their lands retained more organic matter and thus were higher in yields of maize than early Euro-American farms in North America. [20]

Society and culture

Maize, beans, and squash, whether grown individually or together, have a very long history in the Americas. [5] The process to develop the agricultural knowledge for cultivation took place over a 5,000 to 6,500 year period. Squash was domesticated first, with maize second and beans third. [21] [22] Squash was first domesticated some 8,000–10,000 years ago. [23] [24]

Cahokian, Mississippian and Muscogee culture

From 800 AD, Three Sisters crop organization was used in the largest Native American city north of the Rio Grande known as Cahokia, located in the Mississippi floodplain to the east of modern St. Louis, Missouri. It spanned over 13 km2 and supported populations of at least thousands. [25] Cahokia was notable for its delineated community zones, including those for administration, several residential areas, and a large agricultural complex. [25] Domesticated squash, gourds, and maize were initially grown alongside wild beans; domesticated beans were not grown at Cahokia until 1250. [26] The cultivation of the Three Sisters crops by Cahokian residents produced a food surplus large enough to support Cahokia's expanded population, as well as further cultures throughout the extended Mississippi River system such as those of the Mississippian and Muscogee. [25]

There is evidence that Cahokia held at least one great feast around 1050-1100 AD. The food served at these gatherings included, alongside a variety of other plants and animals, several domesticated squash varieties, maize, and wild beans. [26] Food that needed to be processed, like cornmeal, would commonly be prepared at the feast site alongside non-food items that gave the feasts ritual or ceremonial importance. [26]

Eventual overuse of the environment in the areas surrounding Cahokia began to degrade the land. As the surrounding woodlands were cleared through overuse, runoff frequently flooded the crop fields throughout the growing season, limiting the ability to grow the squash, maize, and corn Cahokia subsisted upon. [25] By c.1350, the Cahokia site had been mostly abandoned and the large population dispersed, though the Mississippian and Muscogee cultures continued to thrive until c.1600, when contact with Spanish explorers brought Eurasian diseases, death, and cultural collapse. [25]

Haudenosaunee culture

Historic marker in Madison County, New York Grain pits.JPG
Historic marker in Madison County, New York

In the Handbook of North American Indians , the Three Sisters are called the "foundation of (Iroquois) subsistence", allowing the Haudenosaunee or Iroquois to develop the institutions of sedentary life. [27] The Three Sisters appear prominently in Haudenosaunee oral traditions and ceremonies, such as Iroquois myths and the Haudenosaunee Thanksgiving Address. [28]

According to legend, the Three Sisters grew out of Earth Woman's dead body. During the time of creation, Sky Woman fell to Earth, where she had a daughter named Earth Woman. With the west wind, Earth Woman conceived twin sons. The first twin, Sapling, was born normally, but his evil twin brother, Flint, was so impatient that he came out of his mother's side, killing her during childbirth. As Earth Woman died, either she wished for her body to sustain the people [29] or Sky Woman sowed on her grave the seeds she had brought when she fell to Earth, but never planted before. [30] Out of Earth Woman's body parts grew various plants: the spirits of the corn, beans, and squash came from her breasts, hands, and navel respectively; sunflowers from her legs; strawberries from her heart; tobacco from her head; and purple potatoes or sunchokes from her feet.

It is said that in 1779, Seneca Chief Handsome Lake wished to die after the US military killed Haudenosaunee communities and villagers. Handsome Lake, grief-stricken, envisioned a visit by the spirits of the Three Sisters, prompting him to return to and re-teach his fellow Haudenosaunee their traditional agricultural practices. [31]

Researchers in the early 20th century described more than a dozen varieties of maize and similar numbers of bean varieties, as well as many types of squash, such as pumpkin and winter squash, grown in Haudenosaunee communities. The first academic description of the Three Sisters cropping system in 1910 reported that the Iroquois preferred to plant the three crops together, since it took less time and effort than planting them individually, and because they believed the plants were "guarded by three inseparable spirits and would not thrive apart". [5]

Among the Haudenosaunee, women were responsible for cultivation and distribution of the three crops, which raised their social status. Male roles traditionally included extended periods of travel, such as for hunting expeditions, diplomatic missions, or military raids. Men took part in the initial preparation for the planting of the Three Sisters by clearing the planting ground, after which groups of related women, working communally, performed the planting, weeding, and harvesting. [32] Based on archaeological findings, paleobotanist John Hart concludes that the Haudenosaunee began growing the three crops as a polyculture sometime after 700 BP. [5] The Haudenosaunee frequently traded their crops, so the need for each crop could vary substantially from year to year. Jane Mt. Pleasant surmises that the Haudenosaunee may have typically inter-planted the three crops, but they could also have planted monocultures of the individual crops to meet specific needs. [5]

Maya culture

The Maya diet focused on the Three Sisters. Maize was the central component of the diet of the ancient Maya and figured prominently in Maya mythology and ideology. Archaeological evidence suggests that Chapalote-Nal-Tel was the dominant maize species, though it is likely others were being exploited also. [33]

See also

Related Research Articles

Vegetable farming is the growing of vegetables for human consumption. The practice probably started in several parts of the world over ten thousand years ago, with families growing vegetables for their own consumption or to trade locally. At first manual labour was used but in time livestock were domesticated and the ground could be turned by the plough. More recently, mechanisation has revolutionised vegetable farming with nearly all processes being able to be performed by machine. Specialist producers grow the particular crops that do well in their locality. New methods—such as aquaponics, raised beds and cultivation under glass—are used. Marketing can be done locally in farmer's markets, traditional markets or pick-your-own operations, or farmers can contract their whole crops to wholesalers, canners or retailers.

<span class="mw-page-title-main">Companion planting</span> Agricultural technique

Companion planting in gardening and agriculture is the planting of different crops in proximity for any of a number of different reasons, including weed suppression, pest control, pollination, providing habitat for beneficial insects, maximizing use of space, and to otherwise increase crop productivity. Companion planting is a form of polyculture.

<span class="mw-page-title-main">Agriculture in Mesoamerica</span> Account of archaic North American agriculture

Agriculture in Mesoamerica dates to the Archaic period of Mesoamerican chronology. At the beginning of the Archaic period, the Early Hunters of the late Pleistocene era led nomadic lifestyles, relying on hunting and gathering for sustenance. However, the nomadic lifestyle that dominated the late Pleistocene and the early Archaic slowly transitioned into a more sedentary lifestyle as the hunter gatherer micro-bands in the region began to cultivate wild plants. The cultivation of these plants provided security to the Mesoamericans, allowing them to increase surplus of "starvation foods" near seasonal camps; this surplus could be utilized when hunting was bad, during times of drought, and when resources were low. The cultivation of plants could have been started purposefully, or by accident. The former could have been done by bringing a wild plant closer to a camp site, or to a frequented area, so it was easier access and collect. The latter could have happened as certain plant seeds were eaten and not fully digested, causing these plants to grow wherever human habitation would take them.

<span class="mw-page-title-main">Intercropping</span> Multiple cropping practice involving growing two or more crops in proximity

Intercropping is a multiple cropping practice that involves the cultivation of two or more crops simultaneously on the same field, a form of polyculture. The most common goal of intercropping is to produce a greater yield on a given piece of land by making use of resources or ecological processes that would otherwise not be utilized by a single crop.

<span class="mw-page-title-main">Polyculture</span> Growing multiple crops together in agriculture

In agriculture, polyculture is the practice of growing more than one crop species together in the same place at the same time, in contrast to monoculture, which had become the dominant approach in developed countries by 1950. Traditional examples include the intercropping of the Three Sisters, namely maize, beans, and squashes, by indigenous peoples of Central and North America, the rice-fish systems of Asia, and the complex mixed cropping systems of Nigeria.

The Huron-Wendat Nation is an Iroquoian-speaking nation that was established in the 17th century. In the French language, used by most members of the First Nation, they are known as the Nation Huronne-Wendat. The French gave the nickname “Huron” to the Wendat, from the French word "hure" meaning “boar's head” because of the hairstyle of Huron men, who had their hair standing in bristles on their heads. Wendat (Quendat) was their confederacy name, meaning “people of the island” or "dwellers on a peninsula."

In agriculture, monocropping is the practice of growing a single crop year after year on the same land. Maize, soybeans, and wheat are three common crops often monocropped. Monocropping is also referred to as continuous cropping, as in "continuous corn." Monocropping allows for farmers to have consistent crops throughout their entire farm. They can plant only the most profitable crop, use the same seed, pest control, machinery, and growing method on their entire farm, which may increase overall farm profitability.

<span class="mw-page-title-main">History of agriculture</span>

Agriculture began independently in different parts of the globe, and included a diverse range of taxa. At least eleven separate regions of the Old and New World were involved as independent centers of origin. The development of agriculture about 12,000 years ago changed the way humans lived. They switched from nomadic hunter-gatherer lifestyles to permanent settlements and farming.

Domesticated plants of Mesoamerica, established by agricultural developments and practices over several thousand years of pre-Columbian history, include maize and capsicum. A list of Mesoamerican cultivars and staples:

<span class="mw-page-title-main">Indigenous peoples of the Northeastern Woodlands</span> Native peoples in Eastern Canada and Northeastern United States

Indigenous peoples of the Northeastern Woodlands include Native American tribes and First Nation bands residing in or originating from a cultural area encompassing the northeastern and Midwest United States and southeastern Canada. It is part of a broader grouping known as the Eastern Woodlands. The Northeastern Woodlands is divided into three major areas: the Coastal, Saint Lawrence Lowlands, and Great Lakes-Riverine zones.

<span class="mw-page-title-main">Eastern Agricultural Complex</span> Agricultural practices of pre-historic native cultures in the eastern United States and Canada

The Eastern Agricultural Complex in the woodlands of eastern North America was one of about 10 independent centers of plant domestication in the pre-historic world. Incipient agriculture dates back to about 5300 BCE. By about 1800 BCE the Native Americans of the woodlands were cultivating several species of food plants, thus beginning a transition from a hunter-gatherer economy to agriculture. After 200 BCE when maize from Mexico was introduced to the Eastern Woodlands, the Native Americans of the eastern United States and adjacent Canada slowly changed from growing local indigenous plants to a maize-based agricultural economy. The cultivation of local indigenous plants other than squash and sunflower declined and was eventually abandoned. The formerly domesticated plants returned to their wild forms.

<span class="mw-page-title-main">Ancient Maya cuisine</span> Diet of the Ancient Mesoamerican civilization

Ancient Maya cuisine was varied and extensive. Many different types of resources were consumed, including maritime, flora, and faunal material, and food was obtained or produced through strategies such as hunting, foraging, and large-scale agricultural production. Plant domestication concentrated upon several core foods, the most important of which was maize.

<span class="mw-page-title-main">Intensive crop farming</span> Modern form of farming

Intensive crop farming is a modern industrialized form of crop farming. Intensive crop farming's methods include innovation in agricultural machinery, farming methods, genetic engineering technology, techniques for achieving economies of scale in production, the creation of new markets for consumption, patent protection of genetic information, and global trade. These methods are widespread in developed nations.

<span class="mw-page-title-main">Maize</span> Genus of grass cultivated as a food crop

Maize, also known as corn in North American and Australian English, is a tall stout grass that produces cereal grain. It was domesticated by indigenous peoples in southern Mexico about 9,000 years ago from wild teosinte. Native Americans planted it alongside beans and squashes in the Three Sisters polyculture. The leafy stalk of the plant gives rise to male inflorescences or tassels which produce pollen, and female inflorescences called ears which yield grain, known as kernels or seeds. In modern commercial varieties, these are usually yellow or white; other varieties can be of many colors.

<span class="mw-page-title-main">Pumpkin</span> Category of culinary winter Cucurbita squashes

A pumpkin, in English-language vernacular, is a cultivated winter squash in the genus Cucurbita. The term is most commonly applied to round, orange-colored squash varieties, though it does not possess a scientific definition and may be used in reference to many different squashes of varied appearance.

<span class="mw-page-title-main">Chitemene</span>

Chitemene, from the ciBemba word meaning “place where branches have been cut for a garden”, is a system of slash and burn agriculture practiced throughout northern Zambia. It involves coppicing or pollarding of standing trees in a primary or secondary growth Miombo woodland, stacking of the cut biomass, and eventual burning of the cut biomass in order to create a thicker layer of ash than would be possible with in situ burning. Crops such as maize, finger millet, sorghum, or cassava are then planted in the burned area.

Indigenous horticulture is practised in various ways across all inhabited continents. Indigenous refers to the native peoples of a given area and horticulture is the practice of small-scale intercropping.

<span class="mw-page-title-main">Prehistoric agriculture on the Great Plains</span>

Agriculture on the precontact Great Plains describes the agriculture of the Indigenous peoples of the Great Plains of the United States and southern Canada in the Pre-Columbian era and before extensive contact with European explorers, which in most areas occurred by 1750. The principal crops grown by Indian farmers were maize (corn), beans, and squash, including pumpkins. Sunflowers, goosefoot, tobacco, gourds, and plums, were also grown.

<span class="mw-page-title-main">Pre-Columbian cuisine</span>

Pre-Columbian cuisine refers to the cuisine consumed by the Indigenous peoples of the Americas before Christopher Columbus and other European explorers explored the region and introduced crops and livestock from Europe. Though the Columbian Exchange introduced many new animals and plants to the Americas, Indigenous civilizations already existed there, including the Aztec, Maya, Incan, as well as various Native Americans in North America. The development of agriculture allowed the many different cultures to transition from hunting to staying in one place. A major element of this cuisine is maize (corn), which began being grown in central Mexico. Other crops that flourished in the Americas include amaranth, wild rice, and lima beans.

Jane Mount Pleasant is an American agricultural scientist and associate professor emerita at Cornell University.


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Further reading