Other scientists, impatient with the ear-to-row method, gravitated to the new science of genetics. In 1900 three European botanists independently rediscovered the paper Austrian monk Gregor Mendel had published in 1866 on pea hybridization. Mendel had shown that particles (genes) code for traits in pea plants, and after 1900 scientists extended his insight to other plants and animals. American geneticist George Harrison Shull, in Cold Spring Harbor, New York, chose to work with corn because it differed from peas in that it cross-fertilized rather than self-fertilized, and Shull wished to know whether Mendel’s laws of inheritance held for crossfertilizing as well as inbreeding populations. The crucial insight came in 1909 when Shull realized that inbreeding would reduce corn to several uniform populations, with each population similar to a variety of peas in its uniformity of genes. A breeder could then hybridize corn as Mendel had hybridized peas.
Hybridization held out the possibility of imparting heterosis, or hybrid vigor, to corn plants. For centuries humans had known that hybrids―the mule, for example―have greater vigor than their parents. In corn, hybrid vigor might display itself as high yield, resistance to diseases, insects and drought, stalk strength, or some combination of desirable traits.
Although simple in conception, the practice of breeding corn for hybrid vigor challenged a generation of agronomists. The problem lies in the biology of corn, which, as we have seen, cross-fertilizes rather than self-fertilizes. The tassel, which contains the pollen, and the silk, which holds the ovule, are far apart in corn, and wind carries the pollen from one plant to the silk of another. To inbreed corn, an agronomist or farmer or anyone who knows the anatomy of a corn plant must cover the tassel and silk of a plant to prevent pollen from one plant from blowing onto the silk of another. When the tassel is mature, the breeder collects the pollen and spreads it on the silk of the same plant. Several generations of inbreeding produce homozygous lines that breed true, as a variety of peas does. In turning the natural process of crossbreeding on its head, however, inbreeding weakens corn, producing scrawny ears with fewer seeds than the parents. This paucity gives the breeder enough seed to make a cross on a tiny plot but too little to make a cross on the scale that farmers need for their fields. As long as the seed yield was small, hybrid corn remained a curiosity rather than a commercial venture. But in 1917 agronomist Donald F. Jones at the Connecticut Agricultural Experiment Station got past the seed bottleneck by crossing four inbred lines over two generations. Jones crossed the four inbreds in two groups of two to yield two hybrids, and then crossed these two hybrids to produce one second-generation hybrid. Because this method required two generations of breeding, Jones called this hybrid a double cross to distinguish it from the single cross, a hybrid produced by one cross of two inbreds over one generation.
Sunday, May 1, 2011
Saturday, April 30, 2011
The Era Before Hybrid Corn
Since the 19th century, the U.S. Department of Agriculture, the agricultural colleges, and the experiment stations had bred crops for yield and resistance to diseases, insects, and drought, but by 1900 this work had not affected the lives of most farmers. They judged a crop by inspection, saving seed for planting the next year from plants that yielded well or manifested no damage from insects or disease. The farmer saved several ears of corn, for example, through the winter. A few weeks before planting he wrapped a single kernel from each ear in a wet cloth, planting in the spring seed from the ears whose kernels germinated and discarding those ears whose kernels did not germinate. This brand of agriculture required no science, only a keen eye and attention to detail.
Much of the efforts of scientists and farmers concentrated on corn, an indigenous grass that humans had grown for millennia. In the early 20th century, the Corn Show swept the Corn Belt of the Midwest. An annual contest analogous to the county fair, the Corn Show trumpeted the virtues of rural life and clean living and was as much about civic boosterism as it was about judging corn. The Corn Show substituted beauty for economics, eschewing yield as the criterion for evaluating corn. Rather, judges prized large ears with straight rows, full and uniform kernels, and no bird or insect damage. The winner claimed bragging rights in the county.
Agricultural scientists made the rounds at the Corn Show, renewing acquaintances and sharing their latest research in an informal setting. Some scientists championed the Corn Show for making farmers careful observers of their crop, but others derided the emphasis on aesthetics. In their view yield was the only measure of corn that mattered, and they set to work with the aim of breeding high-yielding varieties regardless of how these varieties looked.
In 1905 agronomist Cyril George Hopkins at the Illinois Agricultural Experiment Station devised the ear-to-row method of breeding corn. Hopkins collected ears from several corn plants, planting the seed from each in its own row. Because all plants in a row were siblings Hopkins could easily maintain the pedigree of each plant. Hopkins hoped that by keeping seed from only the highest-yielding row and repeating the ear-to-row method he would select for corn with progressively higher yield. Although the ear-to-row method allowed Hopkins to derive corn with high protein and oil, he made no headway in yield.
Much of the efforts of scientists and farmers concentrated on corn, an indigenous grass that humans had grown for millennia. In the early 20th century, the Corn Show swept the Corn Belt of the Midwest. An annual contest analogous to the county fair, the Corn Show trumpeted the virtues of rural life and clean living and was as much about civic boosterism as it was about judging corn. The Corn Show substituted beauty for economics, eschewing yield as the criterion for evaluating corn. Rather, judges prized large ears with straight rows, full and uniform kernels, and no bird or insect damage. The winner claimed bragging rights in the county.
Agricultural scientists made the rounds at the Corn Show, renewing acquaintances and sharing their latest research in an informal setting. Some scientists championed the Corn Show for making farmers careful observers of their crop, but others derided the emphasis on aesthetics. In their view yield was the only measure of corn that mattered, and they set to work with the aim of breeding high-yielding varieties regardless of how these varieties looked.
In 1905 agronomist Cyril George Hopkins at the Illinois Agricultural Experiment Station devised the ear-to-row method of breeding corn. Hopkins collected ears from several corn plants, planting the seed from each in its own row. Because all plants in a row were siblings Hopkins could easily maintain the pedigree of each plant. Hopkins hoped that by keeping seed from only the highest-yielding row and repeating the ear-to-row method he would select for corn with progressively higher yield. Although the ear-to-row method allowed Hopkins to derive corn with high protein and oil, he made no headway in yield.
Friday, April 29, 2011
The Gasoline Tractor
Eschewing the automobile, Iowa inventors Charles Hart and Charles Parr in 1901 built the fi rst gasoline tractor with the wide frame of the steam tractor, a low center of gravity, and low gearing. Like the steam tractor, the Hart-Parr tractor was heavy at 10 tons and had a wide turning radius. By 1906 Hart and Parr had pared the weight to 5 tons, increased horsepower to thirty, and began using the term tractor for their machine. As did Ford in the auto industry, Hart and Parr aimed to mass-produce the tractor and to standardize parts. By one estimate, more than thirty firms were manufacturing some 2,000 tractors a year by 1909. The first tractors, with studded steel wheels and no rubber tires, sacrificed comfort for traction and did not immediately replace the horse. Rather than decrease, the number of horses on U.S. farms increased from roughly 4 million in 1910 to 4.5 million in 1916.
Two events turned farmers toward the tractor. First, epidemics of spinal meningitis and blackleg swept American stables in the late 1910s, leaving farmers short of their traditional source of traction. Second, World War I heightened the demand for labor and food. The Allies, desperate for horses to pull materiel and supplies, inundated the United States with orders. The Avery Company of Peoria, Illinois, was one company among many to turn the war to its advantage, in 1914 declaring the sale of horses to the Allies a patriotic duty―a shrewd act given the high price of both horses and feed. The proceeds of these sales, the Avery Company hoped, would go to buy its tractors. The war siphoned off not only horses but also men, who entered the military or took jobs in the city at greater rates. Short of horses and laborers, American farms went from having 4,000 tractors in 1911 to 250,000 in 1920.
By then, John Deere, International Harvester, and Ford were vying for the market. Henry Ford, who had grown up on a farm and sought to improve agriculture as he had travel, in 1915 built his first tractor, the Tracford, boasting that it could do the work of twelve horses and touting its simplicity, durability, and ease of operation. Ford priced it at $250, nearly half the $495 that Happy Farm Tractor Company, for example, charged and less than the $325 of the Model T. Ford unveiled the Fordson tractor in 1917, selling more than 7,000 tractors that year and more than any other manufacturer in 1918. International Harvester rather than Ford, however, made the real innovations, building in the 1920s the Farmall, a narrow tractor that had a small turning radius and so could cultivate and harvest the row crops of the Midwest and South, not merely the wheat of the West. In the 1920s the corn picker complemented the tractor in the Midwest and mechanized the last phase of corn culture.
The tractor came with an ideology of efficiency that shaped the lives of farmers. The agricultural colleges and experiment stations had in the 19th century urged the farmer to be scientific in his work, by which they meant a willingness to apply the results of experiments on the farm. Now, in the era of the tractor, the colleges and experiment stations wanted farmers to be businessmen in addition to receptors of science. Whereas the horse could advance both work and leisure, the tractor could further only the industrialization of agriculture. The tractor enabled farmers to cultivate more land than had been possible with the horse, and with an increase in the scale of operations came the need to compartmentalize every component of work. Gone was the woman of the prairie who broke the sod alongside her husband. He now devolved on her the record keeping necessary to analyze every facet of the business and to satisfy creditors who had loaned them the money to buy a tractor and its associated gadgets. Her work was in the house and his on the land. Gone, too, were the days when children had to help with farm work, particularly during planting and harvest, tasks the tractor could manage on its own. Instead, children spent more time in school, and some even went to college. The towns and cities that had drawn men and women to the factory during World War I now enticed the young to their college campuses. The agricultural colleges were both a source of information for farmers and a lure to their children. With a mixture of pride and regret, parents watched their children graduate from these colleges as engineers and entomologists rather than return to the land as farmers.
With the industrialization of agriculture, the tractor shaped labor to its rhythm. The horse had walked no more than two miles an hour, the limit at which a human can walk without undue fatigue, but the tractor covered ground at an unremitting five miles an hour without the need to rest. The tractor kept the farmer on the move for days that stretched to eighteen hours. The routine of planting or another chore came to resemble the monotony of the big rig on an unvarying stretch of highway. Farmers suffered back pain from jostling, particularly before the introduction of rubber tires on the tractor, and hearing loss from the drone of the engine. Bereft of the romanticism of the horse, the tractor made the farmer more an operator of machines than a tender of plants. Business acumen and an attention to commodity prices meant more in the machine age than an intuitive ability to gauge the time at which a corn plant silks.
The tractor sharpened the distinction between owner and worker. The freeholder of the Midwest and West owned a tractor, whereas the tenant and sharecropper of the South, too poor to get credit from a bank, made do with the horse or the mule, a hybrid of the horse and donkey. The migrant laborer likewise was too poor to own a tractor. On the bottom rungs of the agricultural ladder, the tenant, sharecropper, and landless laborer failed to reap the rewards of the machine age.
The pace of mechanization slackened during the Great Depression, with the number of tractors in the United States holding constant at roughly 1 million between 1931 and 1934. Their incomes dwindling, farmers had little to invest in technology during these years. Between 1930 and 1935, investment in farm equipment fell by $336 million as labor became the substitute for technology and capital. Men who had lost their job in a factory returned to relatives in the countryside to work part-time. Awash in labor, farmers had neither the money nor an immediate incentive to adopt new technology.
The production of materiel during World War II lifted the United States out of the Great Depression and restored farmers to prosperity. Those who had forgone technology during the 1930s out of necessity were able to buy the latest implements: tractors with rubber tires and the ability to cover five miles an hour in the field and twenty on the road, disk plows, eight row planters, and corn and cotton pickers. In the 1960s agricultural engineers developed machines that plowed, planted, and applied fertilizer in a single pass. In the 1970s tractors increased from sixty to two hundred horsepower. In the 1980s air-conditioned cabs became standard, and in the 1990s the first use of satellites enabled farmers to plow, plant, cultivate, and harvest in perfectly straight rows that do not overlap. Computers told farmers the yield of a crop while they were harvesting it and projected the amount and type of fertilizer, insecticide, and herbicide they would need the next year.
These technologies complicated the lives of farmers. The agricultural colleges and experiment stations urged them to modernize by adopting the newest tractor or combine, but these purchases indebted farmers, increasing their anxiety about their ability to repay loans in an era of low commodity prices. This anxiety heightened for farmers who could not insulate themselves from global forces. American farmers in the late 20th century could do nothing to influence the price of wheat in Argentina, and yet a bumper harvest there might diminish the price of wheat in North Dakota. Indebted and buffeted by forces outside their control, farmers were also beset by technical challenges. They needed specialized knowledge to understand the increasingly technical reports of agribusiness firms and to use the latest software. The lives of farmers in 2000 focused on reading technical literature, troubleshooting software, keeping abreast of commodity prices and projections for the future, and adhering to the maintenance schedule for a twenty-four-row planter. In the 20th century, technology had made the farmer a manager of information and implements.
Two events turned farmers toward the tractor. First, epidemics of spinal meningitis and blackleg swept American stables in the late 1910s, leaving farmers short of their traditional source of traction. Second, World War I heightened the demand for labor and food. The Allies, desperate for horses to pull materiel and supplies, inundated the United States with orders. The Avery Company of Peoria, Illinois, was one company among many to turn the war to its advantage, in 1914 declaring the sale of horses to the Allies a patriotic duty―a shrewd act given the high price of both horses and feed. The proceeds of these sales, the Avery Company hoped, would go to buy its tractors. The war siphoned off not only horses but also men, who entered the military or took jobs in the city at greater rates. Short of horses and laborers, American farms went from having 4,000 tractors in 1911 to 250,000 in 1920.
By then, John Deere, International Harvester, and Ford were vying for the market. Henry Ford, who had grown up on a farm and sought to improve agriculture as he had travel, in 1915 built his first tractor, the Tracford, boasting that it could do the work of twelve horses and touting its simplicity, durability, and ease of operation. Ford priced it at $250, nearly half the $495 that Happy Farm Tractor Company, for example, charged and less than the $325 of the Model T. Ford unveiled the Fordson tractor in 1917, selling more than 7,000 tractors that year and more than any other manufacturer in 1918. International Harvester rather than Ford, however, made the real innovations, building in the 1920s the Farmall, a narrow tractor that had a small turning radius and so could cultivate and harvest the row crops of the Midwest and South, not merely the wheat of the West. In the 1920s the corn picker complemented the tractor in the Midwest and mechanized the last phase of corn culture.
The tractor came with an ideology of efficiency that shaped the lives of farmers. The agricultural colleges and experiment stations had in the 19th century urged the farmer to be scientific in his work, by which they meant a willingness to apply the results of experiments on the farm. Now, in the era of the tractor, the colleges and experiment stations wanted farmers to be businessmen in addition to receptors of science. Whereas the horse could advance both work and leisure, the tractor could further only the industrialization of agriculture. The tractor enabled farmers to cultivate more land than had been possible with the horse, and with an increase in the scale of operations came the need to compartmentalize every component of work. Gone was the woman of the prairie who broke the sod alongside her husband. He now devolved on her the record keeping necessary to analyze every facet of the business and to satisfy creditors who had loaned them the money to buy a tractor and its associated gadgets. Her work was in the house and his on the land. Gone, too, were the days when children had to help with farm work, particularly during planting and harvest, tasks the tractor could manage on its own. Instead, children spent more time in school, and some even went to college. The towns and cities that had drawn men and women to the factory during World War I now enticed the young to their college campuses. The agricultural colleges were both a source of information for farmers and a lure to their children. With a mixture of pride and regret, parents watched their children graduate from these colleges as engineers and entomologists rather than return to the land as farmers.
With the industrialization of agriculture, the tractor shaped labor to its rhythm. The horse had walked no more than two miles an hour, the limit at which a human can walk without undue fatigue, but the tractor covered ground at an unremitting five miles an hour without the need to rest. The tractor kept the farmer on the move for days that stretched to eighteen hours. The routine of planting or another chore came to resemble the monotony of the big rig on an unvarying stretch of highway. Farmers suffered back pain from jostling, particularly before the introduction of rubber tires on the tractor, and hearing loss from the drone of the engine. Bereft of the romanticism of the horse, the tractor made the farmer more an operator of machines than a tender of plants. Business acumen and an attention to commodity prices meant more in the machine age than an intuitive ability to gauge the time at which a corn plant silks.
The tractor sharpened the distinction between owner and worker. The freeholder of the Midwest and West owned a tractor, whereas the tenant and sharecropper of the South, too poor to get credit from a bank, made do with the horse or the mule, a hybrid of the horse and donkey. The migrant laborer likewise was too poor to own a tractor. On the bottom rungs of the agricultural ladder, the tenant, sharecropper, and landless laborer failed to reap the rewards of the machine age.
The pace of mechanization slackened during the Great Depression, with the number of tractors in the United States holding constant at roughly 1 million between 1931 and 1934. Their incomes dwindling, farmers had little to invest in technology during these years. Between 1930 and 1935, investment in farm equipment fell by $336 million as labor became the substitute for technology and capital. Men who had lost their job in a factory returned to relatives in the countryside to work part-time. Awash in labor, farmers had neither the money nor an immediate incentive to adopt new technology.
The production of materiel during World War II lifted the United States out of the Great Depression and restored farmers to prosperity. Those who had forgone technology during the 1930s out of necessity were able to buy the latest implements: tractors with rubber tires and the ability to cover five miles an hour in the field and twenty on the road, disk plows, eight row planters, and corn and cotton pickers. In the 1960s agricultural engineers developed machines that plowed, planted, and applied fertilizer in a single pass. In the 1970s tractors increased from sixty to two hundred horsepower. In the 1980s air-conditioned cabs became standard, and in the 1990s the first use of satellites enabled farmers to plow, plant, cultivate, and harvest in perfectly straight rows that do not overlap. Computers told farmers the yield of a crop while they were harvesting it and projected the amount and type of fertilizer, insecticide, and herbicide they would need the next year.
These technologies complicated the lives of farmers. The agricultural colleges and experiment stations urged them to modernize by adopting the newest tractor or combine, but these purchases indebted farmers, increasing their anxiety about their ability to repay loans in an era of low commodity prices. This anxiety heightened for farmers who could not insulate themselves from global forces. American farmers in the late 20th century could do nothing to influence the price of wheat in Argentina, and yet a bumper harvest there might diminish the price of wheat in North Dakota. Indebted and buffeted by forces outside their control, farmers were also beset by technical challenges. They needed specialized knowledge to understand the increasingly technical reports of agribusiness firms and to use the latest software. The lives of farmers in 2000 focused on reading technical literature, troubleshooting software, keeping abreast of commodity prices and projections for the future, and adhering to the maintenance schedule for a twenty-four-row planter. In the 20th century, technology had made the farmer a manager of information and implements.
Wednesday, April 27, 2011
The Steam Tractor and Automobile
Early efforts to supplant the horse were not promising. By 1900 dozens of small manufacturers churned out some 5,000 steam tractors a year. Large and heavy, the steam tractor carried a quantity of water and coal. A gang of four men guided the tractor, stoked the engine with coal, and replenished the water. Although the steam tractor hitched to a combine was capable of harvesting 100 acres a day, the tractor was difficult to maneuver and had a large turning radius. Only with difficulty could the steam tractor cover uneven ground, and it bogged down in the mud. Ravenous in its consumption of labor as well as of coal and water, the steam tractor maintained the large workforce that had been a feature of agriculture in the era of the horse.
No better than the steam engine in its first manifestation on the farm was the gasoline engine. Manufacturers in the first years of the 20th century filled the pages of Implement Trade Journal, a weekly whose subscribers were largely farmers, with ads for stationary gasoline engines, but these could not be a source of traction. Mounted on a chassis, the gasoline engine instead took to the road as the automobile. As early as 1903, the year Henry Ford founded the Ford Motor Company, farmers hitched their plows to the automobile. They could not, however, walk fast enough to keep pace with it, and the plow skimmed the ground rather than digging a furrow.
No better than the steam engine in its first manifestation on the farm was the gasoline engine. Manufacturers in the first years of the 20th century filled the pages of Implement Trade Journal, a weekly whose subscribers were largely farmers, with ads for stationary gasoline engines, but these could not be a source of traction. Mounted on a chassis, the gasoline engine instead took to the road as the automobile. As early as 1903, the year Henry Ford founded the Ford Motor Company, farmers hitched their plows to the automobile. They could not, however, walk fast enough to keep pace with it, and the plow skimmed the ground rather than digging a furrow.
Tuesday, April 26, 2011
The Era Before Tractors
In 1901 Secretary of Agriculture James “Tama” Wilson dismissed Thomas Edison’s claim that technology would soon replace the horse on the farm. To be sure, Wilson acknowledged a role for new modes of transit. The electric railroad, Wilson believed, would entice urbanites to settle the countryside and ease the commute from farm to city. But Wilson doubted the electric railroad or other contraptions would dethrone the horse, which had provided traction on the farm for centuries. Wilson was quick to identify the fl aws of the automobile, which could not, he judged, traverse uneven ground or drive through mud. Agriculture in the early 20th century seemed to demand more horses rather than fewer, particularly in the West, where farms were large and labor scarce. Farmers on the large tracts in the Dakotas, Washington, and Oregon used combines so heavy that they required as many as thirty-three teams of horses to pull them. These combines were themselves state-of-the-art technology, cutting grain in a swath of fourteen to twenty feet and threshing and bundling it. The demands of planting, cultivating, and harvesting crops led farmers either to maintain a stable of horses or to hire the job. The combine cut the stalk near the ground. Once cut, the grain entered the thresher, which shook seed from the stalk. The thresher channeled the stalk to a straw stack and the grain to sacks. Teams of harvesters began work in June, moving north with the harvest to the Dakotas and to Montana by September. The combine seemed to prove that the horse and technology fed off each other and formed an interlocking system.
Integral to technology at the turn of the century, the horse shaped labor, the use of farmland, and the working lives of farmers. The horse could not be switched on and off like a lightbulb but required year-round care. The family short of labor hired a man to organize horses for work and to care for them. The horse thus heightened the demand for labor and kept men on the farm who might otherwise have sought work in the cities. The horse also commandeered its share of the harvest. The farmer had to set aside land to feed his horses: in parts of the Midwest he grew oats for his horses on as much as one-third of the land. What the farmer did not feed his own horses he sold as fodder to farmers from the South and West. Under these circumstances, one would have been rash to join Edison in forecasting the disappearance of the horse.
Integral to technology at the turn of the century, the horse shaped labor, the use of farmland, and the working lives of farmers. The horse could not be switched on and off like a lightbulb but required year-round care. The family short of labor hired a man to organize horses for work and to care for them. The horse thus heightened the demand for labor and kept men on the farm who might otherwise have sought work in the cities. The horse also commandeered its share of the harvest. The farmer had to set aside land to feed his horses: in parts of the Midwest he grew oats for his horses on as much as one-third of the land. What the farmer did not feed his own horses he sold as fodder to farmers from the South and West. Under these circumstances, one would have been rash to join Edison in forecasting the disappearance of the horse.
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