MINIMUM TILLAGE TRIALS AT PINNEY PURDUE FARM, WANATAH, INDIANA
Research Progress Report 49
March 1963
D. R. Griffith, Pinney Purdue Farm and H. M. Galloway, Agronomy Department
Summary
Tillage trials for corn began in 1960 at the Pinney Purdue Farm to demonstrate the principles of minimum tillage and the benefits from lower production costs, increased water retention, less soil compaction and erosion and easier weed control. Trials were conducted on Tracy loam, Runnymede loam and Edwards muck soils.
Three year average yields and returns above tillage and spray costs are given in Table 2. Even with unusually severe climatic factors, minimum tillage with no special equipment was about equal to conventional tillage in returns over the 3 year period.
Minimum tillage practices were tried in 1962 on fall plowed Runnymede loam soil. Results are shown in Table 3. There was little difference in corn yield for any of the pre-plant tillage treatments used. Corn yields with no seed bed preparation were equal to those where normal preparation was used. Weed control and stand with one spring tooth harrowing just before planting appeared to be equally as good as with discing once and spring toothing once.
Experimental Procedure
Tracy loam is a light brown, medium textured soil that is very well drained and easily worked in the spring. Runnymede loam is a dark colored, poorly drained soil with enough clay in the surface layer to cause serious tillage problems in the spring unless plowed under ideal conditions. The third
major soil on the farm is Edwards muck, a shallow organic soil with the well decomposed surface layer varying from 8 to 14 inches in depth,
On the loam soils, practices referred to as conventional tillage include discing once or twice and spring tooth harrowing once or twice, depending on weed growth and soil conditions. On muck, conventional tillage was plowing early and spike tooth harrowing 2 or 3 times. Plow and plant, in all cases, refers to planting in plowed soil with no special attachments for the planter. Wheel track refers to planting in plowed soil with the corn planter shoes following the tractor wheel tracks by offsetting the planter hitch.
Results and Discussion
Results from the demonstration trials for the past 3 years are given in Table 1.
The trials were repeated at 2 planting dates on the loam soils in 1961. All yields for the loam soils are actual picker-sheller harvests converted to 15 1/2 percent moisture. Since these are bulk yields with no measure of variation within plots, emphasis should not be placed on small yield differences. Yields on the muck are an average of hand harvests --no picker losses are accounted for.
Several unusual environmental factors affected yields in certain of these trials. Corn on the Runnymede loam in 1960 developed a severe nitrogen deficiency due to heavy applications of high carbon/nitrogen ratio manure and a relatively cool, wet growing season. Under these conditions of nitrogen stress,
PURDUE UNIVERSITY • Agricultural Experiment Station • Lafayette, Indiana