2008 Great Plains Soil Fertility Conference

This week I attended the 2008 Great Plains Soil Fertility Conference, held biennially in Denver Colorado. This program is put on by the International Plant Nutrition Institute and is attended by over 100 Industry and Academic Agronomy Researchers.

Over 40 research papers are presented in this 2-day program. While the pace of the presentations is quite fast there is ample time to discuss ideas, and new agronomy techniques with many of agricultures best-known researchers.

Jerry Hatfield presented “The Implications of Biofuels Production on Soil Productivity”. While removal of crop residue after harvest is viewed as a major source of cellulosic material, the implications need to be considered. Removal of large amounts of nutrients, decrease in soil organic matter, decrease is soil water holding capacity, leading to severe soil crusting and other environmental impacts.

Mr. Hatfield has authored many papers on soil quality, organic matter and carbon. So many I didn’t even consider counting them. In one of his previous papers on achieving high yields he states,

“Achieving high yields is not an art but requires the implementation of an understanding of the principles that affect yield. To achieve high yields requires patience to first improve the soil and then begin to adopt management strategies that increase the efficiency of water, solar radiation, and N use. Evaluation of how these factors respond each season for the crops grown in the field and then compare against the county average will determine if progress is being made toward achieving the higher yields.”

Understanding what you are doing, why your doing it, and measuring the results is what it takes to achieve high yields.

Dr. Robert Miller gave a great presentation on "Impact of Grid Point Sampling Intensity on Phosphorus and Potassium Uncertainty”. What this means is, if you are grid sampling, are they pulling enough soil cores for the composite to be sure that it is an accurate test of what is actually in the soil. Though his research he found that full tillage, minimal tillage and no-till needed different amounts of cores to be sure of accurate sampling. Full tillage means the soil is more uniformly mixed so 6-8 cores per sample point gives an accurate test, in minimal tillage shoot for 8-12. For no-till the best accuracy will require between 26-40 cores. Since no one has the time to do that many, we have to settle for less accuracy and pull 12-14 cores. This gives a 20% variability in the sample readings.

While not all the presentations are directly related to the crops and climate most of our customer’s farm, I always come away with new and helpful information. You must constantly looking for new information to increase yields, start with the basics, (soil sampling, liming, building nutrient levels) and build on that.