[Editor’s note: Tim Kimpel passed away in June 2012. The following final report was written by Collin Etters who worked with Tim on his project.]
We tested two crops, soybeans and corn, under four variables. We replicated all four variables twice for accuracy. Each variable had to deal with time of aeration. One variable was 30 days before planting, the next was 15 days before planting, the third was the day before planting and the fourth was 30 days before planting and fitted down.
PREVIOUS SUSTAINABLE AGRICULTURE PRACTICES
Aerating soil and controlled grazing. We have been a certified organic farm for four years. We use sustainable methods of weed control, pest managment, nutrient management, etc.
* To test the impact of aeration on crops prior to planting
* To determine how the timing of tillage (cover crops) will affect the quality and yield of crops
The four variables included:
1. aeratoin 30 days before planting
2. aeration 15 days before planting
3. aeration the day before planting
4. aeration 30 days before planting, disced over and fitted back down
The tests we took measured the amount of carbon dioxide in the soil at certain points in each plot. We believed this would tell us the amount of microorganisms in the soil. We also believed that more microorganisms would increase crop growth and yield.
Aeration changed the amount of oxygen in the soil for microorganisms to consume and reproduce at a healthy rate.
The tests were concluded by a simple yield test conducted in each plot.
The results seemed to lean toward aeration 15 days prior to planting as the best choice. I believe 30 days prior was too much and the microbiology moved out or died before the crops were planted to stimulate growth; aeration the day before planting didn’t allow enough oxygen in.
We expected aeration 30 days before planting to be more beneficial than it was.
Next time I imagine we would lower the time before planting to 20, 15, and 10 days before.
It is important to note that the summer of 2012 we experienced a severe drought.
This grant allowed the necessary equipment to measure CO2 levels.
The CO2 levels didn’t show much of a correlation between aeration and crop yield as we expected it would.
I would tell other farmers that two week prior aeration showed the best yield results using no fertilizer.
Something as simple as the timing in which they prepare their fields could make a big response in yields using no extra fertilizers.