Submitted to: Soil & Tillage Research
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/1/2007
Publication Date: 3/1/2007
Citation: Lal, R., Reicosky, D.C., Hanson, J.D. 2007. Evolution of the Plow over 10,000 Years and the Rationale for No-till Farming. Soil & Tillage Research. 93:1-12. Interpretive Summary: The beginning of civilization depended on agriculture for food production -- so does civilization's future. Intensive tillage and use of heavy machinery and agricultural production systems were a cause of mixed blessings. The specific objective is to present a historical perspective on the development of civilization and its dependence on the plow-based agriculture. The soil and environmental impacts of intensive tillage are discussed and the rationale for adopting less intensive forms of tillage with more emphasis on minimum soil disturbance, continuous crop residue cover, and diverse crop rotations are described. Accelerated soil erosion plagued the earth since the dawn of settled agriculture, and has been a major issue in the rise and fall of early civilization. Soil erosion has become a global issue with regard to its on-site impact on productivity and agricultural sustainability. Both water and wind erosion are exacerbated by plow tillage. The agricultural revolution transformed the landscape, ecosystems, vegetation, soils and water resources. These transformations had far reaching and often irreversible impact on the cycles of water and other elements. While it is certainly not a panacea, conversion of plow tillage to no-till farming can address some of the issues by providing alternatives that are environmentally and economically compatible and sustainable while maintaining a high degree of social acceptability. Understanding the role of plow tillage in greenhouse gas emission will enable intelligent policy decisions for improved environmental quality. These results are significant to farmers and policy makers in that intensive tillage results in substantial short-term gaseous losses of carbon dioxide. This information will assist scientists and engineers in developing improved tillage methods to minimize the gaseous loss and to improve soil carbon management. Farmers can develop and utilize new management techniques for enhancing soil carbon by increasing the quantity and quality of crop residues and by changing the type and intensity of tillage. This information will be of direct benefit to the farmers to enable them to maintain crop production with minimal impact on air quality and the environment.
Technical Abstract: Agriculture originated 10 to 13 millennia ago in the Fertile Crescent of the Near East, mostly along the Tigris, Euphrates, Nile, Indus and Yangtze River valleys and was introduced into Greece and southeast Europe > 8000 years ago. Sumerian and other civilizations developed a wide variety of simple tools (digging sticks) to place and cover seed in the soil that led to more complex paddle-shaped spades or hoes pulled by human or animals. A wooden plow, called "ard," was developed in Mesopotamia about 4000 to 6000 BC that led to the "Triptolemos ard" named after the Greek god and hero. Historical documents and archaeological evidence illustrate the "mystique" of tillage implements that were thought to "nourish the earth" and to "break the drought" as is evidenced in several ancient texts. The ard evolved into the "Roman plow," with an iron plowshare, described by Vergil around 1 AD and was used in Europe until the 5th century. It further evolved into a soil inverting plow during 8th to 10th century. In the U.S., a moldboard plow used was designed by Thomas Jefferson in 1784, patented by Charles Newfold in 1796, and marketed in 1830s as a cast iron plow by a blacksmith named John Deere. Use of the plow expanded rapidly with the introduction of the "steam horse" in 1910 and instigated severe soil erosion and environmental degradation culminating in the Dust Bowl of 1930s. The transition from the moldboard plow through forms of conservation tillage to no till began with the development of 2,4-D after World War II. No till is presently practiced on about 95 million hectares globally. The no-till technologies are very effective in minimizing soil and crop residue disturbance, controlling soil evaporation, minimizing erosion losses, sequestering C in soil and reducing energy needs. However, no-till is effective only with the use of crop residue as mulch, which has numerous competing uses. No-till farming can reduce yield in poorly drained, clayey soils where springs are cold and wet, and site-specific research is needed to enhance its applicability.