Micronutrients Can Deliver Big Results
As we’ve met with small groups of area farmers this winter, our key focus has been on ideas that have a very good chance to provide a solid return on investment. One area that can be overlooked, but is critical to plant performance, is secondary nutrients and micronutrients.
The way we measure where we are in our soils at this point in time is through soil testing. We’re analyzing soil pH, organic matter, CEC, P, K, calcium, and magnesium. What is overlooked, however, is a very important secondary nutrient—sulfur—and the micronutrients.
This past growing season, we put together a tissue sampling program—for both corn and soybeans—to look at where a plant was in regard to micronutrients and sulfur at various stages of plant growth. When it comes to micronutrients, soil sampling is not the most reliable source of information. Tissue sampling does, however, tell you what is going on at a given point in time. Our intent was to sample on a timely enough basis to treat any deficiencies found.
We conducted this testing in a multitude of fields spread throughout our footprint and treated where deficiencies were realized. After harvest, I combined all the data from roughly 40 fields, then parsed it by growth stage and placed the results in one of three buckets: adequate, deficient, or will likely respond to additional nutrition. The results were very interesting.
The three micronutrients that stood out in corn were zinc, manganese, and boron. We saw some highly responsive indicators for those three elements, so we are looking at a low-dosage foliar application of those micronutrients in fields where we saw those indicators.
We really didn’t get a large enough dataset in soybeans to draw any solid conclusions, but we plan to continue the program in both corn and soybeans to validate the data we collected this year. Going forward, we’ll also be comparing the data to soil test results to see if we can find any correlations there.
Moving from micronutrients to primary and secondary nutrients, we took a close look at nitrogen and sulfur. We tied those two together because they react similarly in the soil, from the standpoint that we apply primarily non-plant-available forms that can be converted rather rapidly to available forms. For example, ammonia to ammonium nitrate and elemental sulfur to sulfate. In those plant-available forms, they’re leachable.
We apply nitrogen regularly in advance of planting and in season, but we generally don’t do anything for sulfur. A 200-bushel corn crop will remove 16 pounds of elemental sulfur per acre.
With the scrubbing of power plants, sulfur dioxide that used to fall in rain is gone. The only natural source of sulfur now is through plant matter decomposition, which is difficult to measure from year to year.
So, we’ve made plans to address this need with a unique product that provides sulfur and nitrogen in one application—a combination of 32% nitrogen and ammonium thiosulfate. This is a new product concept we are launching this year. This product can be applied either preplant or sidedressed.
The other topic of intense discussion in our meetings has been applications that have paid this past year. I requested any yield monitor maps from the sales team that showed results of grower side-by-side comparisons. Most of the maps I got back were fungicide/insecticide applications on soybeans, with consistent four-bushel responses and with occasional increases up to six bushels.
We’re advising growers to investigate this for themselves, and to set up a trial situation so you can determine what the actual difference is under your conditions and farming practices.
Finally, protocols for 2015 products and concepts are nearly complete, and we have an exciting list of items we’re looking to study this coming growing season. Plan to take advantage of our Innovation Farm and plot tours, and please ask us what we’re seeing as the year progresses.