Humanities › History & Culture History of American Agriculture American Agriculture 1776–1990 Share Flipboard Email Print Stephen Simpson/Getty Images History & Culture Inventions Famous Inventions Famous Inventors Patents & Trademarks Invention Timelines Computers & The Internet American History African American History African History Ancient History and Culture Asian History European History Genealogy Latin American History Medieval & Renaissance History Military History The 20th Century Women's History View More By Mary Bellis Mary Bellis Inventions Expert Mary Bellis covered inventions and inventors for ThoughtCo for 18 years. She is known for her independent films and documentaries, including one about Alexander Graham Bell. Learn about our Editorial Process Updated on August 27, 2021 The history of American agriculture (1776–1990) covers the period from the first English settlers to the modern day. Below are detailed timelines covering farm machinery and technology, transportation, life on the farm, farmers and the land, and crops and livestock. 01 of 03 Agricultural Advances in the United States, 1775–1889 ideabug/Getty Images 1776–1800 During the latter part of the 18th century, farmers relied on oxen and horses to power crude wooden plows. All sowing was accomplished using a hand-held hoe, reaping of hay and grain with a sickle, and threshing with a flail. But in the 1790s, the horse-drawn cradle and scythe were introduced, the first of several inventions. 16th century—Spanish cattle introduced into the Southwest 17th century—Small land grants commonly made to individual settlers; large tracts often granted to well-connected colonists 1619—First enslaved African people brought to Virginia; by 1700, enslaved people were displacing southern indentured servants 17th and 18th centuries—All forms of domestic livestock, except turkeys, were imported at some time 17th and 18th centuries—Crops borrowed from Native Americans included maize, sweet potatoes, tomatoes, pumpkins, gourds, squashes, watermelons, beans, grapes, berries, pecans, black walnuts, peanuts, maple sugar, tobacco, and cotton; white potatoes indigenous to South America 17th and 18th centuries—New U.S. crops from Europe included clover, alfalfa, timothy, small grains, and fruits and vegetables 17th and 18th centuries—enslaved African people introduced grain and sweet sorghum, melons, okra, and peanuts 18th century—English farmers settled in New England villages; Dutch, German, Swedish, Scotch-Irish, and English farmers settled on isolated Middle Colony farmsteads; English and some French farmers settled on plantations in Tidewater and on isolated Southern Colony farmsteads in Piedmont; Spanish immigrants, mostly lower-middle-class and indentured servants, settled the Southwest and California. 18th century—Tobacco was the chief cash crop of the South 18th century—Ideas of progress, human perfectibility, rationality, and scientific improvement flourished in the New World 18th century—Small family farms predominated, except for plantations in southern coastal areas; housing ranged from crude log cabins to substantial frame, brick, or stone houses; farm families manufactured many necessities 1776—Continental Congress offered land grants for service in the Continental Army 1785, 1787—Ordinances of 1785 and 1787 provided for survey, sale, and government of northwestern lands 1790—Total population: 3,929,214, Farmers made up about 90% of labor force 1790—The U.S. area settled extended westward an average of 255 miles; parts of the frontier crossed the Appalachians 1790-1830—Sparse immigration into the United States, mostly from the British Isles 1793—First Merino sheep imported 1793—Invention of cotton gin 1794—Thomas Jefferson's moldboard of least resistance tested 1794—Lancaster Turnpike opened, first successful toll road 1795–1815—The sheep industry in New England was greatly emphasized 1796—Public Land Act of 1796 authorized Federal land sales to the public in minimum 640-acre plots at $2 per acre of credit 1797—Charles Newbold patented first cast-iron plow 1800–1830 Inventions during the early decades of the 19th century were aimed at automation and preservation. 1800–1830—The era of turnpike building (toll roads) improved communication and commerce between settlements 1800—Total population: 5,308,483 1803—Louisiana Purchase 1805–1815—Cotton began to replace tobacco as the chief southern cash crop 1807—Robert Fulton demonstrated the practicability of steamboats 1810—Total population: 7,239,881 1810–1815—Demand for Merino sheep sweeps the country 1810–1830—Transfer of manufactures from the farm and home to the shop and factory was greatly accelerated 1815–1820—Steamboats became important in western trade 1815–1825—Competition with western farm areas began to force New England farmers out of wheat and meat production and into dairying, trucking, and, later, tobacco production 1815–1830—Cotton became the most important cash crop in the Old South 1819— Jethro Wood patented an iron plow with interchangeable parts 1819—Florida and other land acquired through the treaty with Spain 1819– 1925—U.S. food canning industry established 1820—Total population: 9,638,453 1820—Land Law of 1820 allowed purchasers to buy as little as 80 acres of public land for a minimum price of $1.25 an acre; credit system abolished 1825—Erie Canal finished 1825–1840—Era of canal building The 1830s By the 1830s, about 250-300 labor-hours were required to produce 100 bushels (5 acres) of wheat using a walking plow, brush harrow, hand broadcast of seed, sickle, and flail. 1830—Peter Cooper's railroad steam engine, the Tom Thumb, ran 13 miles 1830—Total population: 12,866,020 1830—The Mississippi River formed the approximate frontier boundary The 1830s—Beginning of railroad era 1830–1837—Land speculation boom 1830s–1850s—Improved transportation to the West forced eastern staple growers into more varied production for nearby urban centers 1834—McCormick reaper patented 1834—John Lane began to manufacture plows faced with steel saw blades 1836–1862—Patent Office collected agricultural information and distributed seeds 1837—John Deere and Leonard Andrus began manufacturing steel plows 1837—Practical threshing machine patented 1839—Anti-rent war in New York, a protest against the continued collection of quitrents The 1840s The growing use of factory-made agricultural machinery increased the farmers' need for cash and encouraged commercial farming. 1840—Justos Liebig's Organic Chemistry appeared 1840–1850—New York, Pennsylvania, and Ohio were the chief wheat States 1840–1860—Hereford, Ayrshire, Galloway, Jersey, and Holstein cattle were imported and bred 1840–1860—Growth in manufacturing brought many laborsaving devices to the farm home 1840–1860—Rural housing improved with use of balloon-frame construction 1840—Total population: 17,069,453; Farm population: 9,012,000 (estimated), Farmers made up 69% of labor force 1840—3,000 miles of railroad track had been constructed 1841—Practical grain drill patented 1841—Preemption Act gave squatters first rights to buy land 1842—First grain elevator, Buffalo, NY 1844—Practical mowing machine patented 1844—Success of the telegraph revolutionized communications 1845—Mail volume increased as postage rated lowered 1845–1853—Texas, Oregon, the Mexican cession, and the Gadsden Purchase were added to the Union 1845–1855—The potato famine in Ireland and the German Revolution of 1848 greatly increased immigration 1845–1857—Plank road movement 1846—First herdbook for Shorthorn cattle 1849—First poultry exhibition in the United States 1847—Irrigation began in Utah 1849—Mixed chemical fertilizers sold commercially 1849—Gold Rush The 1850s By 1850, about 75–90 labor-hours were required to produce 100 bushels of corn (2-1/2 acres) with walking plow, harrow, and hand planting. 1850—Total population: 23,191,786; Farm population: 11,680,000 (estimated); Farmers made up 64% of labor force; Number of farms: 1,449,000; Average acres: 203 The 1850s—Commercial corn and wheat belts began to develop; wheat occupied the newer and cheaper land west of the corn areas and was constantly being forced westward by rising land values and the encroachment of the corn areas The 1850s—Alfalfa is grown on the west coast The 1850s—Successful farming on the prairies began 1850—With the California gold rush, the frontier bypassed the Great Plains and the Rockies and moved to the Pacific coast 1850–1862—Free land was a vital rural issue The 1850s—Major railroad trunk lines from eastern cities crossed the Appalachian Mountains The 1850s—Steam and clipper ships improved overseas transportation 1850–1870—Expanded market demand for agricultural products brought adoption of improved technology and resulting increases in farm production 1854—Self-governing windmill perfected 1854—Graduation Act reduced price of unsold public lands 1856—2-horse straddle-row cultivator patented 1858—Grimm alfalfa introduced 1859–1875—The miners' frontier moved eastward from California toward the westward-moving farmers' and ranchers frontier The 1860s The early 1860s witnessed a dramatic change from hand power to horses, which historians characterize as the first American agricultural revolution 1860—Total population: 31,443,321; Farm population: 15,141,000 (estimated); Farmers made up 58% of labor force; Number of farms: 2,044,000; Average acres: 199 The 1860s—Kerosene lamps became popular The 1860s—The Cotton Belt began to move westward The 1860s—The Corn Belt began stabilizing in its present area 1860—30,000 miles of railroad track had been laid 1860—Wisconsin and Illinois were the chief wheat states 1862—Homestead Act granted 160 acres to settlers who had worked the land 5 years 1865–1870—The sharecropping system in the South replaced the old plantation system that utilized stolen labor, knowledge, and skills from enslaved people 1865–1890—Influx of Scandinavian immigrants 1865–1890—Sod houses common on the prairies 1865-75—Gang plows and sulky plows came into use 1866–1877—Cattle boom accelerated settlement of Great Plains; range wars developed between farmers and ranchers 1866–1986—The days of the cattlemen on the Great Plains 1868—Steam tractors were tried out 1869—Illinois passed first designated "Granger" law regulating railroads 1869—Union Pacific, first transcontinental railroad, completed 1869—Spring-tooth harrow or seedbed preparation appeared The 1870s The most important advance of the 1870s was the use of both silos, and the wide use of deep-well drilling, two advances that enabled larger farms and higher production of marketable surpluses. 1870—Total population: 38,558,371; Farm population: 18,373,000 (estimated); Farmers made up 53% of labor force; Number of farms: 2,660,000; Average acres: 153 The 1870s —Refrigerator railroad cars introduced, increasing national markets for fruits and vegetables The 1870s—Increased specialization in farm production 1870—Illinois, Iowa, and Ohio were the chief wheat states 1874—Glidden barbed wire patented 1874—Availability of barbed wire allowed fencing of rangeland, ending the era of unrestricted, open-range grazing 1874–1876—Grasshopper plagues serious in the West 1877—U.S. Entomological Commission established for work on grasshopper control The 1880s 1880—Total population: 50,155,783; Farm population: 22,981,000 (estimated); Farmers made up 49% of labor force; Number of farms: 4,009,000; Average acres: 134 The 1880s—Heavy agricultural settlement on the Great Plains began The 1880s—The cattle industry moved into the western and southwestern Great Plains1880—Most humid land already settled 1880—William Deering put 3,000 twine binders on the market1880—160,506 miles of railroad in operation 1882—Bordeau mixture (fungicide) discovered in France and soon used in the United States1882—Robert Koch discovered tubercle bacillus 1880–1914—Most immigrants were from southeastern Europe Mid–1880s—Texas was becoming the chief cotton state 1884-90—Horse-drawn combine used in Pacific coast wheat areas1886–1887—Blizzards, following drought and overgrazing, disastrous to northern Great Plains cattle industry1887—Interstate Commerce Act1887–1897—Drought reduced settlement on the Great Plains1889—Bureau of Animal Industry discovered carrier of tick fever The 1890s By 1890, labor costs continued to decrease, with only 35–40 labor-hours required to produce 100 bushels (2-1/2 acres) of corn, because of technological advances of the 2-bottom gang plow, disk and peg-tooth harrow, and 2-row planters; and 40–50 labor-hours required to produce 100 bushels (5 acres) of wheat with gang plow, seeder, harrow, binder, thresher, wagons, and horses. 1890—Total population: 62,941,714; Farm population: 29,414,000 (estimated); Farmers made up 43% of labor force; Number of farms: 4,565,000; Average acres: 136 The 1890s—Increases in land under cultivation and number of immigrants becoming farmers caused great rise in agricultural output The 1890s—Agriculture became increasingly mechanized and commercialized1890—Census showed that the frontier settlement era was over1890—Minnesota, California, and Illinois were the chief wheat states 1890—Babcock butterfat test devised 1890-95—Cream separators came into wide use1890-99—Average annual consumption of commercial fertilizer: 1,845,900 tons 1890—Most basic potentialities of agricultural machinery that was dependent on horsepower had been discovered1892—Boll weevil crossed the Rio Grande and began to spread north and east 1892—Eradication of pleuropneumonia 1893–1905—Period of railroad consolidation1895—George B. Seldon was granted U.S. Patent for automobile 1896—Rural Free Delivery (RFD) started1899—Improved method of anthrax inoculation 02 of 03 Agricultural Advances in the United States, 1900–1949 Migrant laborers work in a field in Southern California in 1920. Kirn Vintage Stock/Getty Images The 1900s The first decades of the 20th century saw the efforts of George Washington Carver, director of agricultural research at Tuskegee Institute, whose pioneering work finding new uses for peanuts, sweet potatoes, and soybeans helped to diversify southern agriculture. 1900—Total population: 75,994,266; Farm population: 29,414,000 (estimated); Farmers made up 38% of labor force; Number of farms: 5,740,000; Average acres: 147 1900–1909—Average annual consumption of commercial fertilizer: 3,738,300 1900–1910—Turkey red wheat was becoming important as commercial crop 1900–1920—Urban influences on rural life intensified 1900–1920—Continued agricultural settlement on the Great Plains 1900–1920—Extensive experimental work was carried out to breed disease-resistant varieties of plants, to improve plant yield and quality, and to increase the productivity of farm animal strains 1903—Hog cholera serum developed 1904—First serious stem-rust epidemic affecting wheat 1908—Model T Ford paved way for mass production of automobiles 1908—President Roosevelt's Country Life Commission was established and focused attention on the problems of farm wives and the difficulty of keeping children on the farm 1908–1917—Period of the country-life movement 1909—The Wright Brothers demonstrated the airplane The 1910s 1910–1915—Big open-geared gas tractors came into use in areas of extensive farming1910–1919—Average annual consumption of commercial fertilizer: 6,116,700 tons1910–1920—Grain production reached into the most arid sections of the Great Plains 1910–1925—Period of road building accompanied increased use of automobiles 1910–1925—Period of road building accompanied increased use of automobiles 1910–1935—States and territories required tuberculin testing of all entering cattle 1910—North Dakota, Kansas, and Minnesota were the chief wheat states 1910—Durum wheats were becoming important commercial crops1911–1917—Immigration of agricultural workers from Mexico 1912—Marquis wheat introduced 1912—Panama and Colombia sheep developed1915–1920—Enclosed gears developed for tractor1916—Railroad network peaks at 254,000 miles 1916—Stock-Raising Homestead Act1916—Rural Post Roads Act began regular Federal subsidies to road building 1917—Kansas red wheat distributed1917–1920—Federal Government operates railroads during the war emergency1918–1919—Small prairie-type combine with auxiliary engine introduced The 1920s The "Roaring Twenties" affected the agricultural industry, along with the "Good Roads" Movement." 1920—Total population: 105,710,620; Farm population: 31,614,269 (estimated); Farmers made up 27% of labor force; Number of farms: 6,454,000; Average acres: 148 The 1920s—Truckers began to capture trade in perishables and dairy products The 1920s—Movie houses were becoming common in rural areas 1921—Radio broadcasts began 1921—Federal Government gave more aid for farm-to-market roads 1925—Hoch-Smith Resolution required the Interstate Commerce Commission (ICC) to consider agricultural conditions in making railroad rates 1920–1929—Average annual consumption of commercial fertilizer: 6,845,800 tons 1920–1940—Gradual increase in farm production resulted from the expanded use of mechanized power 1924—Immigration Act greatly reduced the number of new immigrants 1926—Cotton-stripper developed for High Plains 1926—Successful light tractor developed 1926—Ceres wheat distributed 1926—First hybrid-seed corn company organized 1926—Targhee sheep developed The 1930s While the damage of the Great Depression and the Dust Bowl lasted for a generation, the farm economy rebounded with advances in better irrigation methods and conservation tillage. 1930—Total population: 122,775,046; Farm population: 30,455,350 (estimated); Farmers made up 21% of labor force; Number of farms: 6,295,000; Average acres: 157; Irrigated acres: 14,633,252 1930–1935—Use of hybrid-seed corn became common in the Corn Belt 1930–1939—Average annual consumption of commercial fertilizer: 6,599,913 tons1930—58% of all farms had cars, 34% had telephones, 13% had electricity The 1930s—All-purpose, rubber-tired tractor with complementary machinery came into wide useThe 1930s—Farm-to-market roads emphasized in Federal roadbuilding 1930—One farmer supplied 9.8 persons in the United States and abroad1930—15–20 labor-hours required to produce 100 bushels (2-1/2 acres) of corn with 2-bottom gang plow, 7-foot tandem disk, 4-section harrow, and 2-row planters, cultivators, and pickers1930—15–20 labor-hours required to produce 100 bushels (5 acres) of wheat with 3-bottom gang plow, tractor, 10-foot tandem disk, harrow, 12-foot combine, and trucks1932–1936—Drought and dust-bowl conditions developed 1934—Executive orders withdrew public lands from settlement, location, sale, or entry1934—Taylor Grazing Act1934—Thatcher wheat distributed 1934—Landrace hogs imported from Denmark 1935—Motor Carrier Act brought trucking under ICC regulation1936—Rural Electrification Act (REA) greatly improved the quality of rural life1938—Cooperative organized for artificial insemination of dairy cattle The 1940s 1940—Total population: 131,820,000; Farm population: 30,840,000 (estimated); Farmers made up 18% of labor force; Number of farms: 6,102,000; Average acres: 175; Irrigated acres: 17,942,968 The 1940s—Many former southern sharecroppers migrated to war-related jobs in cities1940–1949—Average annual consumption of commercial fertilizer: 13,590,466 tons1940s and 1950s—Acreages of crops, such as oats, required for horse and mule feed dropped sharply as farms used more tractors 1940—One farmer supplied 10.7 persons in the United States and abroad1940—58% of all farms had cars, 25% had telephones, 33% had electricity1941–1945— Frozen foods popularized1942—Spindle cotton-picker produced commercially1942—Office of Defense Transportation established to coordinate wartime transport needs1945–1955—Increased use of herbicides and pesticides1945–1970—Change from horses to tractors and the adoption of a group of technological practices characterized the second American agriculture agricultural revolution1945—10–14 labor-hours required to produce 100 bushels (2 acres) of corn with a tractor, 3-bottom plow, 10-foot tandem disk, 4-section harrow, 4-row planters and cultivators, and 2-row picker 1945—42 labor-hours required to produce 100 pounds (2/5 acre) of lint cotton with 2 mules, 1-row plow, 1-row cultivator, hand how, and hand pick 03 of 03 Agricultural Advances in the United States, 1950–1990 A combine harvester, tractor, and a pickup truck in a wheat field during harvest in Oakley, Kansas around 1956. Michael Ochs Archives/Getty Images The 1950s The late 1950s–1960s began the chemical revolution in agricultural science, with the increasing use of anhydrous ammonia as a cheap source of nitrogen spurring higher yields. 1950—Total population: 151,132,000; Farm population: 25,058,000 (estimated); Farmers made up 12.2% of labor force; Number of farms: 5,388,000; Average acres: 216; Irrigated acres: 25,634,869 1950–1959—Average annual consumption of commercial fertilizer: 22,340,666 tons 1950—One farmer supplied 15.5 persons in the United States and abroad The 1950s —Television widely accepted The 1950s—Many rural areas lost population as many farm family members sought outside work The 1950s—Trucks and barges competed successfully for agricultural products as railroad rates rose 1954—Number of tractors on farms exceeded the number of horses and mules for first times 1954—70.9% of all farms had cars, 49% had telephones, 93% had electricity 1954—Social Security coverage extended to farm operators 1955—6–12 labor-hours required to produce 100 bushels (4 acres) of wheat with a tractor, 10-foot plow, 12-foot role weeder, harrow, 14-foot drill, and self-propelled combine, and trucks 1956—Legislation passed providing for Great Plains Conservation Program 1956—Interstate Highway Act The 1960s 1960—Total population: 180,007,000; Farm population: 15,635,000 (estimated); Farmers made up 8.3% of labor force; Number of farms: 3,711,000; Average acres: 303; Irrigated acres: 33,829,000 The 1960s—State legislation increased to keep land in farming The 1960s—Soybean acreage expanded as farmers used soybeans as an alternative to other crops 1960–69—Average annual consumption of commercial fertilizer: 32,373,713 tons 1960—One farmer supplied 25.8 persons in the United States and abroad 1960—96% of corn acreage planted with hybrid seed The 1960s—The financial condition of northeastern railroads deteriorated; rail abandonments accelerated The 1960s—Agricultural shipments by all-cargo planes increased, especially shipments of strawberries and cut flowers 1961—Gaines wheat distributed 1962—REA authorized to finance educational TV in rural areas 1964—Wilderness Act 1965—Farmers made up 6.4% of the labor force 1965—5 labor-hours required to produce 100 pounds (1/5 acre) of lint cotton with a tractor, 2-row stalk cutter, 14-foot disk, 4-row bedder, planter, and cultivator, and 2-row harvester 1965—5 labor-hours required to produce 100 bushels (3 1/3 acres) of wheat with a tractor, 12-foot plow, 14-foot drill, 14-foot self-propelled combine, and trucks 1965—99% of sugar beets harvested mechanically 1965—Federal loans and grants for water/sewer systems began 1966—Fortuna wheat distributed 1968—96% of cotton harvested mechanically 1968—83% of all farms had phones, 98.4% had electricity 1970s By the 1970s, no-tillage agriculture was popularized, increased in usage throughout the period. 1970—Total population: 204,335,000; Farm population: 9,712,000 (estimated); Farmers made up 4.6% of labor force; Number of farms: 2,780,000; Average acres: 3901970—One farmer supplied 75.8 persons in the United States and abroad1970—Plant Variety Protection Act 1970—Nobel Peace Prize awarded to Norman Borlaug for developing high-yielding wheat varieties The 1970s—Rural areas experienced prosperity and in-migration1972–74—Russian grain sale caused massive tie-ups in the rail system1975—90% of all farms had phones, 98.6% had electricity1975—Lancota wheat introduced 1975—2-3 labor-hours required to produce 100 pounds (1/5 acre) of lint cotton with a tractor, 2-row stalk cutter, 20-foot disk, 4 -row bedder and planter, 4-row cultivator with herbicide applicator, and 2-row harvester1975—3-3/4 labor-hours required to produce 100 bushels (3 acres) of wheat with a tractor, 30-foot sweep disk, 27-foot drill, 22-foot self-propelled combine, and trucks1975—3-1/3 labor-hours required to produce 100 bushels (1-1/8 acres) of corn with a tractor, 5-bottom plow, 20-foot tandem disk, planter, 20-foot herbicide applicator, 12-foot self-propelled combine, and trucks1978—Hog cholera officially declared eradicated 1979—Purcell winter wheat introduced The 1980s By the end of the 1880s, farmers were using low-input sustainable agriculture (LISA) techniques to decrease chemical applications. 1980—Total population: 227,020,000; Farm population: 6,051,00; Farmers made up 3.4% of labor force; Number of farms: 2,439,510; Average acres: 426; Irrigated acres: 50,350,000 (1978)The 1980s—More farmers used no-till or low-till methods to curb erosionThe 1980s—Biotechnology became a viable technique for improving crop and livestock products1980—Railroad and trucking industries were deregulatedThe 1980s—For the first time since the 19th century, immigrants (Europeans and Japanese primarily) began to purchase significant acreages of farmland and ranchlandMid-1980s—Hard times and indebtedness affected many farmers in the Midwest1983–1984—Avian influenza of poultry eradicated before it spread beyond a few Pennsylvania counties1986—The Southeast's worst summer drought on record took a severe toll on many farmers 1986—Antismoking campaigns and legislation began to affect the tobacco industry1987—Farmland values bottomed out after a 6-year decline, signaling both a turnaround in the farm economy and increased competition with other countries' exports 1987—1-1/2 to 2 labor-hours required to produce 100 pounds (1/5 acre) of lint cotton with a tractor, 4-row stalk cutter, 20-foot disk, 6-row bedder and planter, 6-row cultivator with herbicide applicator, and 4-row harvester1987—3 labor-hours required to produce 100 bushels (3 acres) of wheat with a tractor, 35-foot sweep disk, 30-foot drill, 25-foot self-propelled combine, and trucks1987—2-3/4 labor-hours required to produce 100 bushels (1-1/8 acres) of corn with a tractor, 5-bottom plow, 25-foot tandem disk, planter, 25-foot herbicide applicator, 15-foot self-propelled combine, and trucks 1988—Scientists warned that the possibility of global warming may affect the future viability of American farming 1988—One of the worst droughts in the nation's history hit midwestern farmers1989—After several slow years, the sale of farm equipment rebounded1989—More farmers began to use low-input sustainable agriculture (LISA) techniques to decrease chemical applications1990—Total population: 246,081,000; Farm population: 4,591,000; Farmers made up 2.6% of labor force; Number of farms: 2,143,150; Average acres: 461; Irrigated acres: 46,386,000 (1987) Cite this Article Format mla apa chicago Your Citation Bellis, Mary. "History of American Agriculture." ThoughtCo, Aug. 27, 2021, thoughtco.com/history-of-american-agriculture-farm-machinery-4074385. Bellis, Mary. (2021, August 27). History of American Agriculture. Retrieved from https://www.thoughtco.com/history-of-american-agriculture-farm-machinery-4074385 Bellis, Mary. "History of American Agriculture." ThoughtCo. https://www.thoughtco.com/history-of-american-agriculture-farm-machinery-4074385 (accessed March 22, 2023). copy citation Watch Now: Your Favorite Food Might Be Going Extinct