By Mike Petersen, PrecisionTillage.com
March 20, 2013 — For many of you, and for us at Orthman Research Farm near Lexington, Neb., the pre-plant tillage operations for spring 2013 will be underway very soon. Tillage via strip-till methods will be our way, but how about many of you as you consider the fertilization part of the puzzle? How will that be happening for you?
We recently attended a good set of meetings in Reno, Nev., at the Western Fertility Conference to learn and interact with industry and research scientists about some gains in fertility management for row crops, small grains, and orchard/fruit crops. The issues of ground water contamination, overland flow issues getting into the major water course of the Mississippi River and major river systems of the west, are challenging the way we growers must consider our operations.
The good folks I met, listened to and spoke with in Reno, Nev., are saying there are nitrogen products on the market that will give better and sustained release to the crops root system over a longer period of time and resist the change from first introduction into the soil profile to convert to nitrate, and leach away before the roots have a chance to access to it in the soil solution.
ESN is a granular urea-coated dry product with micro-thin polymer. This method of release can aid in slowed access to the urea-N product so it does not leach away, gobbled by the microbes or become mineralized so quickly, that the plant root starves for nitrogen when called for by the growing above ground plant.
Another product on the market is Nutrisphere-N by SFP that works a bit differently than ESN, but offers another management alternative for growers on how nitrogen releases into the soil environment. For the strip-tiller, these products offer advanced ways to accomplish higher management of your nitrogen-fertility and feed the plant incrementally. Agrotain by Koch Industries, and Instinct by Dow, are other products to be aware of so nitrogen management is not a ‘willy-nilly’ part of how we furnish the corn, wheat, grain sorghum, dry edibles, cotton, peanuts, etc., with what is needed. As we learn more about these products from trials in each of our regions or even on a neighbor’s ground, we can better feed the crops we grow with the nitrogen.
In the strip-till system where the soil is off to either side of where we strip-till 10 inches deep, it can be 2-to-8 degrees colder, more moist and cause issues of root nitrogen-uptake and maybe even yield reductions early, because the availability is just not there.
Pouring nitrogen via anhydrous ammonia and expecting that because it’s cooler that it will be there when the roots get to it, could be an issue.
It’s a cheaper form of nitrogen, but is it the right one if any of it volitalizes or gets converted too soon? Cavities in the soil, shanked-in and you may see it escaping, warmer than 50 degrees and dry soils are all issues and then 20% is gone. That price differential just evaporated.
Placing a charge of 250-to-300 lbs. per acre and then three inches of rain and the stuff will move even in clay loam soils 10-to-25 inches deeper than where you placed it. In some environments, the roots may never reach the nitrogen and it is lost to never be had. The same can happen to high rates of nitrogen via liquid products.
In this day and age, we are called to be better managers and come out of the shell the old way dad did it and move to spending time to educate how we can do better and wiser. Allocating time to have products within reach of the roots when the demand for nitrogen is there will take new skills when we place it with strip-till tools.
At Orthman Farms, we are using some of the above products and getting positive responses and good yield results in grain and healthier crops.
In California the watchers and monitoring agencies are clamping down on how fertility is managed. In Delaware and Maryland, the environmental agencies by law demand fine-toothed control of N-P fertilization. In segments of the central and eastern Corn Belt states, fall applications of nitrogen products are restricted and certain watersheds are being monitored and evaluated to where growers may only apply 70 lbs.-per-acre — as an example — of nitrogen for a 200 bushels-per-acre corn crop. That is quite restrictive.
In other environments we can still apply high amounts of nitrogen, but at what cost? As a soil scientist and agronomist for Orthman Manufacturing I am going the route of top-flight management with better products that will feed the plant incrementally. We will one day feed the corn we plant only half of what we have conventionally tilled into the soils and still yield 300 bushels-per-acre corn regularly. It has been done in the past three years in the western Corn Belt under intensively managed irrigated corn. Instead of 300-to-350 lbs. of nitrogen-per-acre, researchers applied 140-to-150 lbs.-per-acre. Consider the dollars savings alone.
All of us who grow crops to reach a production goal know it takes fertilizers, either commercial or with use of manures. We know our dollars stretch only so far and our water is stretching us to be better about how we grow crops. We encourage you to place those nutrients in the soil precisely, with the understanding how much will the plant need and when.