Approximately one-half of the people in less developed countriesare farmers. The overwhelming majority of them are like theIqbels, growing enough food to feed themselves, but little more.LDCs are home to 97 percent of the world’s farmers. In contrast,fewer than 2 percent of the people in the United States are farmers.Yet the advanced technology used by these farmers allows them toproduce enough food for people in the United States at a very highstandard, plus food for many people elsewhere in the world.

The previous chapter divided economic activities into pri-mary, secondary, and tertiary sectors. This chapter is concernedwith the principal form of primary-sector economic activity—agriculture. The next two chapters look at the secondary andtertiary sectors.

Geographers study where agriculture is distributed acrossEarth. The most important distinction is what happens to farmproducts. In less developed regions, the farm products are mostoften consumed on or near the farm where they are produced,whereas in MDCs farmers sell what they produce.

Geographers observe a wide variety of agricultural practices.The reason why farming varies around the world relates to thedistribution of cultural and environmental factors across space.Elements of the physical environment, such as climate, soil, andtopography, set broad limits on agricultural practices, and farm-ers make choices to modify the environment in a variety of ways.

Farming is an economic activity that still depends verymuch on the local diversity of environmental and cultural con-ditions in each place. Despite increased knowledge of alterna-tives, farmers practice distinctive agriculture in differentregions and, in fact, on neighboring farms. Broad climate pat-terns influence the crops planted in a region, and local soil con-ditions influence the crops planted on an individual farm.

In each society, farmers possess very specific knowledge oftheir environmental conditions and certain technology for mod-ifying the landscape. Within the limits of their technology, farm-ers choose from a variety of agricultural practices, based ontheir perception of the value of each alternative. These valuesare partly economic and partly cultural. How farmers deal with

their physical environment varies according to dietary prefer-ences, availability of technology, and other cultural traditions.Farmers select agricultural practices based on cultural percep-tions, because a society may hold some foods in high esteemwhile avoiding others.

Although individual farmers may make specific decisions ona very local scale, agriculture is as caught up in theglobalization of the economy as other industries. Agriculture isbig business in MDCs and a major component of internationaltrade connections in LDCs.

After examining the origins and diffusion of agriculture, wewill consider the agricultural practices used in LDCs andMDCs. We will also examine the problems farmers face in eachtype of region. Although each farm has a unique set of physicalconditions and choice of crops, geographers group farms intoseveral types by their distinctive environmental and culturalcharacteristics.

KEY ISSUE 1

Where Did AgricultureOriginate?

■ Origins of Agriculture■ Subsistence and Commercial Agriculture

The origins of agriculture cannot be documented with cer-tainty because it began before recorded history. Scholarstry to reconstruct a logical sequence of events based onfragments of information about ancient agricultural prac-tices and historical environmental conditions. Improve-ments in cultivating plants and domesticating animalsevolved over thousands of years. This section offers anexplanation for the origin and diffusion of agriculture. ■

CASE STUDY / Wheat Farmers in Kansas and PakistanThe Iqbel family grows wheat on its 1-hectare (2.5-acre) plot ofland in the Punjab province of Pakistan in a manner similar tothat of their ancestors. They perform most tasks by hand orwith the help of animals. To irrigate the land, for example, theylift water from a 20-meter (65-foot) well by pushing a waterwheel. More prosperous farmers in Pakistan use bullocks toturn the wheel.

The farm produces about 1,500 kilograms (3,300 pounds)of wheat per year—enough to feed the Iqbel family. Some yearsthey produce a small surplus, which they can sell. They canthen use that money to buy other types of food or householditems. In drought years, however, the crop yield is lower, andthe Iqbel family must receive food from government and inter-national relief organizations.

A world away, in Kansas, the McKinleys farm the prairiesod. Like the Iqbels, they grow wheat in a climate thatreceives little rain. Otherwise, the two farm families lead verydifferent lives. The McKinley family’s farm is 200 times aslarge—200 hectares (500 acres). The McKinleys derive sev-eral hundred times more income from the sale of wheat thando the Iqbels.

The wheat grown on the McKinleys farm is not consumeddirectly by them. Instead, it is sold to a processing companyand ultimately turned into bread wrapped in plastic and sold ina supermarket hundreds of kilometers away. Most of the wheatfrom the Iqbels’ farm is consumed in the village where it isgrown. ■

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Chapter 10: Agriculture 309

Origins of AgricultureAgriculture is deliberate modification of Earth’s surfacethrough cultivation of plants and rearing of animals to obtainsustenance or economic gain. Agriculture originated whenhumans domesticated plants and animals for their use. Theword cultivate means “to care for,” and a crop is any plant cul-tivated by people.

Hunters and GatherersBefore the invention of agriculture, all humans probablyobtained the food they needed for survival through hunting foranimals, fishing, or gathering plants (including berries, nuts,fruits, and roots). Hunters and gatherers lived in small groups,of usually fewer than 50 persons, because a larger numberwould quickly exhaust the available resources within walkingdistance (Figure 10-1). The men hunted game or fished, andthe women collected berries, nuts, and roots. This division oflabor sounds like a stereotype but is based on evidence fromarchaeology and anthropology. They collected food often, per-haps daily. The food search might take only a short time ormuch of the day, depending on local conditions.

The group traveled frequently, establishing new home basesor camps. The direction and frequency of migration dependedon the movement of game and the seasonal growth of plants atvarious locations. We can assume that groups communicatedwith each other concerning hunting rights, intermarriage, andother specific subjects. For the most part, they kept the peaceby steering clear of each other’s territory.

Today, perhaps a quarter-million people, or less than 0.005percent of the world’s population, still survive by hunting andgathering rather than by agriculture. Examples include theSpinifex (also known as Pila Nguru) people, who live in Aus-tralia’s Great Victorian Desert; the Sentinelese people, who live inIndia’s Andaman Islands; and the Bushmen, who live in Botswanaand Namibia. Contemporary hunting and gathering societies areisolated groups living on the periphery of world settlement, butthey provide insight into human customs that prevailed in prehis-toric times, before the invention of agriculture.

Invention of AgricultureWhy did most nomadic groups convert from hunting, gather-ing, and fishing to agriculture? Geographers and other scien-tists agree that agriculture originated in multiple hearthsaround the world. They do not agree on when agriculture orig-inated and diffused, or why.

Southwest Asia was an early center of crop domestication(Figure 10-2). The earliest crops domesticated in SouthwestAsia are thought to have been barley and wheat, around 10,000years ago. Lentil and olive were also early domestications inSouthwest Asia. From this hearth, cultivation diffused west toEurope and east to Central Asia. Rice is now thought to havebeen domesticated in East Asia more than 10,000 years ago,along the Yangtze River in eastern China. Millet was cultivatedat an early date along the Yellow River. Sorghum was domesti-cated in central Africa around 8,000 years ago. Yams may have

been domesticated even earlier. Millet and rice may have beendomesticated in sub-Saharan Africa independently of the hearthin East Asia. From central Africa, domestication of crops proba-bly diffused further south in Africa.

In Latin America, two important hearths of crop domestica-tion are thought to have emerged in Mexico and Peru around4,000 to 5,000 years ago. Mexico is considered a hearth forbeans and cotton, and Peru for potato. Squashes may have beenfirst domesticated in a third hearth in the Americas, in south-eastern present-day United States, as well as in Mexico. Themost important contribution of the Americas to crop domesti-cation, maize (corn), may have emerged in the two hearthsindependently around the same time. From these two hearths,cultivation of maize and other crops diffused northward intoNorth America and southward into tropical South America.

Animals were also domesticated in multiple hearths at variousdates. Southwest Asia is thought to have been the hearth for thedomestication of the largest number of animals that would proveto be most important for agriculture, including cattle, goats, pigs,and sheep, between 8,000 and 9,000 years ago (Figure 10-3).Domestication of the dog is thought to date from around 12,000years ago, also in Southwest Asia. The horse is considered to havebeen domesticated in Central Asia; diffusion of the domesticatedhorse is thought to be associated with the diffusion of the Indo-European language, as discussed in Chapter 5.

Inhabitants of Southwest Asia may have been the first tointegrate cultivation of crops with domestication of herd ani-mals such as cattle, sheep, and goats. These animals were usedto prepare the land before planting seeds and, in turn, were fedpart of the harvested crop. Other animal products, such asmilk, meat, and skins, may have been exploited at a later date.This integration of plants and animals is a fundamental ele-ment of modern agriculture.

Scientists do not agree on whether agriculture originatedprimarily because of environmental factors or cultural factors.Probably a combination of both factors contributed. Thosefavoring environmental reasons point to the coinciding of thefirst domestication of crops and animals with climate change

FIGURE 10-1 Hunting and gathering. Botswana Bushmen dig up wild onionscalled kjon.

310 The Cultural Landscape

berries on the ground to see if they wouldproduce new plants. Subsequent generationslearned to pour water over the site and tointroduce manure and other soil improve-ments. Over thousands of years, plant cultiva-tion apparently evolved from a combinationof accident and deliberate experiment.

That agriculture had multiple originsmeans that, from earliest times, people haveproduced food in distinctive ways in differentregions. This diversity derives from a uniquelegacy of wild plants, climatic conditions, andcultural preferences in each region. Improvedcommunications in recent centuries haveencouraged the diffusion of some plants tovaried locations around the world. Manyplants and animals thrive across a wideportion of Earth’s surface, not just in theirplace of original domestication. Only after1500, for example, were wheat, oats, and

barley introduced to the Western Hemisphere and maize to theEastern Hemisphere.

Subsistence and CommercialAgricultureThe most fundamental differences in agricultural practices arebetween those in LDCs and those in MDCs. Farmers in LDCsgenerally practice subsistence agriculture, whereas farmers inMDCs practice commercial agriculture. Subsistence agriculture,

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FIGURE 10-2 Crop hearths. Agriculture originated in multiple hearths. Domestication of some crops canbe dated back more than 10,000 years.

around 10,000 years ago. This marked the end of the last iceage, when permanent ice cover receded from Earth’s midlati-tudes to polar regions, resulting in a massive redistribution ofhumans, other animals, and plants at that time. Alternatively,human behavior may be primarily responsible for the origin ofagriculture. A preference for living in a fixed place rather thanas nomads may have led hunters and gatherers to build perma-nent settlements and to store surplus vegetation there.

In gathering wild vegetation, people inevitably cut plants anddropped berries, fruits, and seeds. These hunters probablyobserved that, over time, damaged or discarded food producednew plants. They may have deliberately cut plants or dropped

FIGURE 10-3 Animal hearths. Animal domestication also originated in multiple hearths.

found in LDCs, is the production of food primarily for consump-tion by the farmer’s family. Commercial agriculture, found inMDCs, is the production of food primarily for sale off the farm.

The most widely used map of world agricultural regions isbased on work done by geographer Derwent Whittlesey in1936. Whittlesey identified 11 main agricultural regions, plusan area where agriculture was nonexistent. Whittlesey’s 11regions are divided between 5 that are important in LDCs and 6that are important in MDCs (Figure 10-4). Figure 10-4 alsoincludes a small, simplified version of the world climate map(see Figure 1-19).

Similarities between the agriculture and climate maps arestriking. For example, pastoral nomadism is the predominanttype of agriculture in the Middle East, which has a dry climate,whereas shifting cultivation is the predominant type of agricul-ture in central Africa, which has a tropical climate. Note thedivision between southeastern China (warm midlatitude cli-mate, intensive subsistence agriculture with wet rice domi-nant) and northeastern China (cold midlatitude climate,intensive subsistence agriculture with wet rice not dominant).In the United States, much of the West is distinguished fromthe rest of the country according to climate (dry) and agricul-ture (livestock ranching). Thus, agriculture varies between thedry lands and the tropics within LDCs—as well as between thedry lands of LDCs and MDCs.

Because of the problems involved with the concept of envi-ronmental determinism, discussed in Chapter 1, geographersare wary of placing too much emphasis on the role of climate.Cultural preferences (discussed in Chapter 4) also explain agri-cultural differences in areas of similar climate. Hog productionis virtually nonexistent in predominantly Muslim regionsbecause of that religion’s taboo against consuming pork prod-ucts (Figure 4-8). Wine production is relatively low in Africaand Asia, even where the climate is favorable for growinggrapes, because of alcohol avoidance in predominantly non-Christian countries (Figure 4-15).

Five principal features distinguish commercial agriculturefrom subsistence agriculture:

• Purpose of farming• Percentage of farmers in the labor force• Use of machinery• Farm size• Relationship of farming to other businesses

Purpose of FarmingSubsistence and commercial agriculture are undertaken for dif-ferent purposes. In LDCs, most people produce food for theirown consumption. Some surplus may be sold to the govern-ment or to private firms, but the surplus product is not thefarmer’s primary purpose and may not even exist some yearsbecause of growing conditions.

In commercial farming, farmers grow crops and raise ani-mals primarily for sale off the farm rather than for their ownconsumption. Agricultural products are not sold directly toconsumers but to food-processing companies. Large proces-sors, such as General Mills and Kraft, typically sign contractswith commercial farmers to buy their grain, chickens, cattle,

and other output. Farmers may have contracts to sell sugarbeets to sugar refineries, potatoes to distilleries, and oranges tomanufacturers of concentrated juices.

Percentage of Farmers in the Labor ForceIn MDCs, around 5 percent of workers are engaged directly infarming, compared to around 50 percent in LDCs (Figure 10-5).The percentage of farmers is even lower in North America—only around 2 percent. Yet the small percentage of farmers in theUnited States and Canada produces not only enough food forthemselves and the rest of the region but also a surplus to feedpeople elsewhere.

The number of farmers declined dramatically in MDCs dur-ing the twentieth century. The United States had about 6 mil-lion farms in 1940 and 4 million in 1960; the number hasstabilized during the past quarter-century at around 2 million.Both push and pull migration factors have been responsible forthe decline: People were pushed away from farms by lack ofopportunity to earn a decent income, and at the same time theywere pulled to higher-paying jobs in urban areas.

Use of MachineryIn MDCs, a small number of farmers can feed many peoplebecause they rely on machinery to perform work, rather thanrelying on people or animals (Figure 10-6). In LDCs, farmersdo much of the work with hand tools and animal power.

Traditionally, the farmer or local craftspeople made equip-ment from wood, but beginning in the late eighteenth century,factories produced farm machinery. The first all-iron plow wasmade in the 1770s and was followed in the nineteenth and twen-tieth centuries by inventions that made farming less dependenton human or animal power. Tractors, combines, corn pickers,planters, and other factory-made farm machines have replacedor supplemented manual labor.

Transportation improvements have also aided commercialfarmers. The building of railroads in the nineteenth century,and highways and trucks in the twentieth century, haveenabled farmers to transport crops and livestock farther andfaster. Cattle arrive at market heavier and in better conditionwhen transported by truck or train than when driven on hoof.Crops reach markets without spoiling.

Commercial farmers use scientific advances to increase pro-ductivity. Experiments conducted in university laboratories,industry, and research organizations generate new fertilizers, her-bicides, hybrid plants, animal breeds, and farming practices,which produce higher crop yields and healthier animals. Accessto other scientific information has enabled farmers to make moreintelligent decisions concerning proper agricultural practices.Some farmers conduct their own on-farm research.

Electronics also help commercial farmers. Global positioningsystems (GPS) determine the precise coordinates for spreadingdifferent types and amounts of fertilizers. On large ranches, GPSis also used to monitor the location of cattle. Satellite imagerymonitors crop progress. Yield monitors attached to combinesdetermine the precise number of bushels being harvested.

Chapter 10: Agriculture 311

312 The Cultural Landscape

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SUBSISTENCE AGRICULTURELess Developed Countries

FIGURE 10-4 Agriculture and climate. (Top)Simplified climate regions. Compare the broad distri-bution of the major climate regions with the distinc-tive types of agriculture in MDCs and LDCs. (Bottom)Agricultural regions. The major agricultural practicesof the world can be divided into subsistence andcommercial regions. Subsistence regions include thefollowing:

• Shifting cultivation—primarily the tropical regionsof South America, Africa, and Southeast Asia

• Pastoral nomadism—primarily the dry lands ofNorth Africa and Asia

• Intensive subsistence, wet rice dominant—primarily the large population concentrations ofEast and South Asia

• Intensive subsistence, crops other than ricedominant—primarily the large population concen-trations of East and South Asia where growing riceis difficult

Commercial regions include the following:

• Mixed crop and livestock—primarily U.S. Midwestand central Europe

• Dairying—primarily near population clusters inthe northeastern United States, southeastern Canada,and northwestern Europe

• Grain—primarily north-central United States andEastern Europe

• Ranching—primarily the drylands of the westernUnited States, southeastern South America, CentralAsia, southern Africa, and Australia

• Mediterranean—primarily lands surrounding theMediterranean Sea, western United States, and Chile

• Commercial gardening—primarily the southeasternUnited States and southeastern Australia

• Plantation—primarily the tropical and subtropicalregions of Latin America, Africa, and Asia

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Chapter 10: Agriculture 313

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Farm SizeThe average farm size is relatively large in commercialagriculture, especially in the United States and Canada, with U.S.farms averaging about 180 hectares (449 acres). Despite theirsize, most commercial farms in MDCs are family owned andoperated—98 percent in the United States. Commercial farmersfrequently expand their holdings by renting nearby fields.

Commercial agriculture is increasingly dominated by a handfulof large farms. In the United States, the largest 5 percent of farmsproduced 75 percent of the country’s total agriculture. Large size ispartly a consequence of mechanization. Combines, pickers, andother machinery perform most efficiently at very large scales, andtheir considerable expense cannot be justified on a small farm. Asa result of the large size and the high level of mechanization, com-mercial agriculture is an expensive business. Farmers spend hun-dreds of thousands of dollars to buy or rent land and machinerybefore beginning operations. This money is frequently borrowedfrom a bank and repaid after the output is sold.

Although the United States currently has fewer farms andfarmers than in 1900, the amount of land devoted to agriculture

has increased. The United States had 60 percent fewer farms and85 percent fewer farmers in 2000 than in 1900, but 13 percentmore farmland, primarily because of irrigation and reclamation.However, the amount of U.S. farmland has declined from its all-time peak around 1960. Primarily because of the expansion ofurban areas, the United States has been losing 500,000 hectares(1.2 million acres) per year from its 400 million hectares (1 bil-lion acres) of farmland. A more serious problem in the UnitedStates has been the loss of 200,000 hectares (500,000 acres) ofthe most productive farmland, known as prime agriculturalland, as urban areas sprawl into the surrounding countryside(see Contemporary Geographic Tools box).

Relationship of Farming to Other BusinessesCommercial farming is closely tied to other businesses. Thesystem of commercial farming found in the United States andother MDCs has been called agribusiness because the familyfarm is not an isolated activity but is integrated into a large

314 The Cultural Landscape

food-production industry. Commercial farmers make heavy useof modern communications and information technology tostay in touch and keep track of prices, yields, and expenditures.

Although farmers are less than 2 percent of the U.S. laborforce, around 20 percent of U.S. labor works in food produc-tion and services related to agribusiness—food processing,packaging, storing, distributing, and retailing. Agribusinessencompasses such diverse enterprises as tractor manufactur-ing, fertilizer production, and seed distribution. Although mostfarms are owned by individual families, many other aspects ofagribusiness are controlled by large corporations.

KEY ISSUE 2

Where Are AgriculturalRegions in LDCs?

■ Shifting Cultivation■ Pastoral Nomadism■ Intensive Subsistence Agriculture■ Plantation Farming

This section considers four agricultural types characteristicof LDCs—shifting cultivation, pastoral nomadism, inten-sive subsistence, and plantation. Intensive subsistenceagriculture is divided into two regions, depending on thechoice of crop. ■

Shifting CultivationShifting cultivation is practiced in much of the world’s HumidLow-Latitude, or A, climate regions, which have relatively hightemperatures and abundant rainfall (Figure 10-8). It is practicedby roughly 250 million people across 36 million square kilometers(14 million square miles), especially in the tropical rainforests ofSouth America, Central and West Africa, and Southeast Asia.

Characteristics of Shifting CultivationTwo distinctive features of shifting cultivation are:

• Farmers clear land for planting by slashing vegetation andburning the debris (shifting cultivation is sometimes calledslash-and-burn agriculture).

• Farmers grow crops on a cleared field for only a few yearsuntil soil nutrients are depleted and then leave it fallow(nothing planted) for many years so the soil can recover.

People who practice shifting cultivation generally live insmall villages and grow food on the surrounding land, whichthe village controls. Well-recognized boundaries usually sepa-rate neighboring villages.

THE PROCESS OF SHIFTING CULTIVATION. Eachyear villagers designate for planting an area surrounding thesettlement. Before planting, they must remove the densevegetation that typically covers tropical land. Using axes, theycut down most of the trees, sparing only those that areeconomically useful. An efficient strategy is to cut downselected large trees, which bring down smaller trees that mayhave been weakened by notching. The undergrowth is cleared

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FIGURE 10-5 Agricultural workers. The percent of the workforce engaged in agriculture is higher in LDCsthan in MDCs. A priority for all people is to secure the food they need to survive. In LDCs most people workin agriculture to produce the food they and their families require. In MDCs few people are farmers, and mostpeople buy food with money earned by working in factories or offices or by performing other services.