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CHAPTER 1

FARM MACHINERY AND ITS RELATION TO AGRICULTURE

In the beginning, all crops for the sustenance of mankind were produced and prepared by the power of human muscles. Many centuries passed before the power of animal muscles was used to relieve that of the human being. With the discovery of iron, tools were fashioned that further relieved the labor of human muscles. The transition from hand farming to this modern power-farming age was at first slow, but with the development of the steel plow, the internal-combustion engine, the farm tractor, and other modern farm machines, the movement has accelerated beyond the wildest dreams of our forefathers. The changes which occurred during the past decade have so tremendously affected human values that one wonders what effect farm machines of the future will have on our welfare. In fact, there has been more farming progress in the last hundred years than in all the previous history of the world.¹

Progress of Farm Mechanization. In 1855, practically 80 per cent of the population of the United States lived on farms, while in 1955, more than 85 per cent live in towns and cities.

Figure 1–1 shows that

. . . since the peak of farm population in 1916, the trend in the number of persons living on farms has been generally downward. The depression in the 1930’s brought a temporary increase, but World War II with its demand for manpower in industry and the armed forces caused a rapid loss in the farm population. The high level of nonfarm employment prevailing since 1916, together with defense mobilization following the outbreak of hostilities in Korea, have been conducive to a continuation of a relatively high rate of net migration from farms.²

In 1854, farm tools were so crude that each farm worker could produce only enough food for himself and four to five others. By 1920, with improved horse-drawn equipment, the farm worker could support himself and nine others. In 1955, with modern power equipment, the farm worker can support himself and about seventeen others.³

The number of tractors on farms increased from a few giant tractors in 1910 to 4.5 million in 1955. As the number of tractors have increased, the number of horses and mules on farms have decreased to around 4.5 million in 1955. It is obvious that as the number of tractors increased there was also a corresponding increase in farm power machines.

FIG. 1–1. Decline in farm population.

FIG. 1–2. Trend in numbers of horses and mules, and tractors.

In explaining the chart shown in Fig. 1–2, the Bureau of Agricultural Economics states that

At the beginning of World War I work animals provided practically all of the power for operating our field machines and for hauling farm products to primary markets. Now, practically all the hauling of products away from farms is done with machine power, and tractors supply 80 per cent or more of the power for operating field machines. Reduction in horse and mule numbers which has been under way since 1918 has been especially marked in recent years.

Use of tractor power on farms got a major start in World War I. Since 1910 annual increases in tractor numbers have occurred in all years except in the depression period of the early thirties. From January 1940 to January 1954 tractor numbers increased by more than 2.6 million or about 170 per cent.

Of the 1954 tractors, about 4 per cent were crawlers, 7 per cent garden tractors and the remainder factory made wheel and homemade tractors. Of the total tractors, about 1.5 per cent are “homemade.”

A key part of the technological revolution under way in agriculture, and largely a product of it, has been the rapid increase in output per man-hour of labor on farms. Output per man-hour is now the greatest in history. It is now nearly 2 1/3 times that of 40 years ago, with most of the gain having occurred during the last 15 years. This decade and a half witnessed rapid progress in farm mechanization and sharp increases in yields of crops and livestock because of widespread adoption of improved farming practices. These changes have made possible a great rise in total farm output, with fewer man-hours spent at farm work.

It is estimated that in 1954 there were about 2.1 tractors per farm in the United States as compared to 1.2 per farm for the period 1941-1945.¹

Power Equipment Cuts Production Man-hours. The effect of the mechanization of agriculture is shown in the number of man-hours required to grow and harvest an acre of wheat yielding 20 bushels. In 1830, when the grain was sown by hand and harvested by hand with a cradle, 55.7 man-hours were required. In 1896, with the use of a horse-drawn drill and binder, 8.8 man-hours were required, while in 1930, with the tractor-drawn drill and combine, only 3.3 man-hours were necessary.² Newer machines and improved practices in producing spring wheat reduced the required man-hours in 1950 to 1.4 in South Dakota, and to 1.8 in northeastern Montana and southwestern North Dakota. Where summer fallow was practiced, the man-hour requirement per acre was 1.9 in western South Dakota and 2.6 in the central areas of the Dakotas. The per-acre tractor-hours for these areas was 0.8, 1.4, 1.5, and 1.8, respectively.³ The difference in man- and tractor-hours results from the use of self-propelled combines and hauling where no tractors were used. Improved machines and practices have brought about similar reductions in man-hour requirement in the production and harvesting of most field crops, in the relation of farm output to labor input (Fig. 1–3).

There has been more progress in the reduction of man-hours required to grow and harvest an acre of cotton from 1930 to 1955 than in all the previous history of the crop. This resulted from farm-mechanization practices.

Equipment Must Suit the Crops and the Types of Farming. The two major crop systems in the United States are row crops and broadcast crops. The principal row crops are corn, cotton, potatoes, tobacco, and truck crops. Hay, rice, wheat, and the small grains are broadcast crops. Farm machinery can be profitably used with both systems, but the more uses to which a machine can be adapted the less the initial investment in equipment. Certain types of plows and harrows for seedbed preparation have a wide application. Grain drills and combines are adapted for seeding and harvesting of wheat and the small grains, and the combine can also be used for harvesting some row crops, such as sorghum grain and soybeans. With slight modifications, many other types of farm equipment can be used on more than one crop. On the other hand, there are some machines, such as beet and cotton harvesters, that are suitable for one crop only.

FIG. 1–3. Farm output and labor input.

Breeding Crops to Suit Machinery. Certain field crops do not readily lend themselves to machine harvesting. The drooping heads of some varieties of grain sorghum make it difficult to head them without cutting excessively long stems. Plant breeders have now developed varieties of sorghum with straight, erect heads of uniform height that are well adapted to combining. As cotton matures, it produces long vegetative and fruiting branches with an abundance of foliage, which make it difficult to harvest the cotton bolls with machinery. Plant breeders, however, have recently developed types of cotton plants that are more suitable to machine harvesting. Fluffy types are suitable for the picker, and nonfluffy or stormproof types are best harvested by the stripper.

Trend toward Tractor-mounted, Pick-up, and Quick-change Units. When the tractor was first used for the operation of field equipment, all machines were pulled behind the tractor. Specially designed planters and cultivators were mounted on row-crop tractors about 1930. With the development of the power-take-off, other machines, such as mowers and corn pickers, were fitted to and mounted on the tractor. These first tractor-mounted units required considerable labor and time to mount and dismount. They were put together practically piece by piece and taken off in a similar manner. All lifting and adjusting were done by hand levers. Later, units were developed that could be attached as assembled units and lifted with mechanical power lifts. Two- and three-bottom plows were at first considered too heavy to be picked up or lifted as units. In 1955, however, three-bottom moldboard plows, tandem disk harrows, and many other formerly trailing machines are now picked up, while making turns, by means of hydraulic power. Consequently, most farm equipment for cultural purposes is now designed for tractor attachment. The exceptions are self-propelled combines, corn pickers, and cotton pickers.

Farm Management. Farm machines designed for higher speeds, constructed of heat-treated steels, and equipped with more durable bearings will lessen operating time and will lower costs. Terracing and contouring of fields will cause changes in farming practices, both in the types of machinery used and in cropping systems. These and various other factors will materially affect the management of farm labor and equipment.

Rubber Tires for Farm Equipment. When the first edition of Farm Machinery and Equipment was published, in 1929, there were no farm machines equipped with rubber tires. In the second edition, in 1937, only a few machines equipped with rubber tires were shown. The third edition, in 1948, showed rubber tires on most equipment. Now, in 1955, it is fairly rare to see a new farm machine that is not equipped with rubber tires.

The various factors related to the types and use of rubber tires are given in Chap. 6.

REFERENCES

Anderson, K. W.: New Horizons in Farm Machinery Development, Agr. Engin., 33(12):765, 1953.

QUESTIONS AND PROBLEMS

1. Discuss the development and progress of farm mechanization.

2. Explain how power equipment reduces man-hours in crop production.

3. Enumerate machines that can be used in producing two or more crops. List some machines that have a single use.

4. Trace the trend in the development of tractor-mounted and quick-change units.

5. Discuss the use of rubber tires on farm equipment.

¹ Agr. Engin., 34(2):91, 1953; Life, 34(1):62, 1953; 38(1): 54, 1955.

² U.S. Dept. Agr., BAE.

³ U.S. Dept. Agr. Misc. Pub. 630.

¹ Work Simplification News Letter 23, December, 1952.

² U.S. Dept. Agr. Misc. Rpt. 157, 1933.

³ U.S. Dept. Agr., BAE, F. M. 92, Section 4, 1953.