Role of Farm Machinery

Throughout history, farming has been one of the most labor-intensive occupations known to man, from preparing the soil to planting seed to gathering the harvest to processing the crop. Since the first domestication of wheat and other grasses in the Fertile Crescent some 10,000 years ago, a continuous string of inventions has made cultivation and harvest easier, less time-consuming, and created higher yields on available land.

Preparing the Soil

In ancient times, farmers simply scattered seed on the ground and hoped for the best. Natural processes of germination occurred when rainfall was adequate, the soil was fertile, the seed was not eaten by birds or animals, and the wind did not blow it all away. Early farmers eventually discovered that pushing the seed into the ground got better results, and that clearing rocks and other vegetation gave desirable seeds a better chance. Plows to break up the soil and seed drills for planting arrived early in the history of agriculture: plows around 6,000 B.C. and simple seed drills around 1,500 B.C.

Fertilization

Many crops deplete the soil they are planted in, draining the nutrients and yielding poorer and poorer harvests. Early farmers used animal dung to enrich the soil, which also served to keep barnyards free of accumulated manure. In some places, including Japan, human fecal matter was used as fertilizer. In either case, it was spread by hand using carts or barrows, pitchforks, shovels, and human muscle. The manure spreader was invented in an age when most farms still had significant populations of large animals like horses and cows to contribute natural fertilizer.

Harvest

Harvesting the crop is the end goal of cultivation. Successful harvest requires that as little of the crop be wasted in gathering as possible, and that it be done in a timely fashion before the crop becomes over-ripe, rots, or is lost to birds, insects, or wild animals. Specialized machinery exists today to harvest particular crops like wheat, hay, beans, peas, rice, cotton, and many others. Each is designed to gather as much of the "fruit" as possible without damage or loss. In the case of mechanical harvesters like combines, the unusable portion of the plant is discarded in the process.

Types of Machinery

Modern farms use mechanical rakes, tillers, harrows, discs, rock pickers, seeders, and plows to prepare the soil and plant seed. Modern American farms use liquid chemical fertilizers and tractor-pulled sprayer tanks to spread it rather than manure, and harvest machinery depends on the specific crop. A variety of harvesters, diggers, hullers, pickers, and swathers are used, powered by gasoline or diesel.

Feeding the World

Mechanized agriculture allows more land to be cultivated by fewer people, increasing the overall yield, as demonstrated in a comparison of California almond production vs. that of Spain, which has three times California's acreage yet claims only 17 percent of the world's production in comparison with California's 66 percent. Specialty machines like sidehill-leveler combines allow land that ordinarily could not be farmed to be put into cultivation. Machines especially designed for specific crops reduce wastage during harvest while speeding time to market. Without modern machinery used in conjunction with high-yield seed crops, the current world population could not be sustained.

References

• Guns, Germs, and Steel, The Fates of Human Societies, Jared Diamond, 1997
• Encyclopedia Brittanica, 15th ed., 1990
• California Agriculture, University of California

Resources

• History of Horticulture, Jules Janick, Purdue University