Date of Award
Master of Science
The history of tillage and synonymously the history of the plow can be traced back to 6000 B.C. when the first curved, V-shaped tree limb was man drawn to produce a shallow furrow. The plow's history can be followed as an animal-drawn implement to about 1870 when mechanical power became practical and the steam engine began to replace animals. The steam engine later gave way to internal combustion engines and consequently modern tractor-drawn plows.
From the standpoint of its development, the plow is a drawn implement requiring energy input in the form of draft power. According to Soehne (49), power transmission efficiency between tractor tires and the soil can be maintained at about 60 to 65 percent under average soil conditions. This means that 35 to 40 percent of the power produced by the tractor engine is lost when converting to draft power.
More important, however, are the adverse affects on soil physical properties produced by tractors designed for pulling draft implements. Cooper (19) indicates that 80 percent of the total tractor weight is carried on the foot-print made by each rear tractor tire. To multiply this by common conventional tillage practices of six or seven trips over the field to fit the seedbed, plant and cultivate often results in more compact root-bed conditions than before the operations were started.
Allen James Wald
Wald, Allen James, "Evaluation Of Rotary Tillage System For Corn Production" (1968). Graduate Theses and Dissertations. 16251.