2005 Annual Report: Tillage Systems in Corn
The objective of this demonstration is to evaluate the effect of different tillage systems on corn yields and profitability of the enterprise. This is the 15th year for this demonstration.
Methods and Materials
The four most common tillage systems practiced in this region were used for this demonstration. The tillage systems used were: Fall and Spring Disk, Spring Disk, No-till, and Fall Chisel and Spring Disk
Each plot consisted of eight rows spaced 30 inches apart and 250 feet long. Yield results were taken from the center six rows of each plot. The plots were planted on April 25, 2005 with a population of 29,900 seeds/acre into a field that raised soybeans in 2004. Harvest was conducted on September 30, 2005.
In 2005, the highest yielding system was the Spring Disk plots with a yield of 224.7 bu/acre. The lowest yielding system was the Fall & Spring Disk plot which yielded 211.9 bu/ac. The average for the four systems was 221.0 bu/ac with a standard deviation of 6.1 bu/ac.
|Corn Tillage System||Harvest Moisture %||Yield at 15.5%|
|Fall and Spring Disk||14.9||211.9|
|Fall Chisel/Spring Disk||15.1||223.7|
Table 1 - 2005 Corn tillage systems yield results.
Yield results for all four tillage systems are shown above in Table 1 and Figure 1. Perhaps a more valid comparison can be made by looking at the 15-year results of the study as shown in Figure 2.
This long term collection of data allows the weather variable to be minimized since we had greatly varying weather patterns during this time period. During this 15 year period, the No-till system averaged 153.3 bu/acre out-yielding the other tillage systems used. The Fall and Spring Disk treatment had the lowest average of 150.6 bu/ acre.
The most important aspect of the tillage trials is the net bottom line. The application of fertilizer, herbicides, seed, planting and harvesting were identical for each of the tillage systems used. The economic differences shown are a result of the tillage procedures conducted on each plot and the associated costs.
|Corn Tillage System||15 Year Yield|
|Tillage Costs per Acre||Gross Income|
Costs per Acre
|Fall and Spring Disk||150.6||$301.11||$16.64||$284.47|
|Fall Chisel/Spring Disk||151.1||$302.24||$19.69||$282.55|
Table 2. Gross income per acre minus tillage costs over a 15 year period.
Fig 2 - Corn Tillage systems 15 year yield averages.
It is very difficult to estimate tillage costs as each grower’s operating costs will be different. Age and size of the equipment, field shape and size as well as soil type will all effect the tillage costs. A large variable this past season was fuel costs. We have tried to estimate an average cost but most will agree it is below average.
One factor not considered in the economic analysis is labor. It is almost impossible to place a value on a producer’s labor per hour. Therefore, no labor costs are included in the analysis.
Table 2 provides a summary of the gross income per acre minus the costs for the tillage work that was conducted. If we use a value of $2.00 per bushel, over this 15 year period, the no-till plots grossed between $13.56 and $24.08 per acre more than the other tillage systems.
Another important factor that is sometimes not considered is the benefit to the environment of different tillage practices. No-till programs greatly reduce the amount of soil erosion caused by wind and water runoff. Soil particles are the number one contaminant found in the rivers and streams of Northwest Missouri. These particles not only cloud the water but they also may have other pollutants (herbicides, insecticides, fertilizer) adhered to them which may contaminate the water.