Applying anhydrous ammonia is a job few farmers relish, and most would gladly drop like hot rock if an alternative were available. The reasons are simple: it's dangerous, hard to handle, requires special equipment, and involves constant timing with your supplier to be efficient. Unfortunately, NH3 is a superior source of nitrogen - the stuff of life (or at least, yields) for corn.
But there is a subtler side to NH3, I think. Because it is such a pain for humans to handle, we often drift into thinking it must be equally hard on the soil. This correlation is exploited by organic or other detractors via anthropomorphizing the soil.
It is a common and seemingly natural tendency for humans to perceive inanimate objects as having human characteristics, although few believe this to be of significance. Common examples of this tendency include naming cars or begging machines to work. In 1953, the U.S. government began assigning hurricanes names; initially the names were feminine, and shortly thereafter masculine names were introduced.
The fact that that dirt contains living organisms is not news, of course. Extending this liveliness to the particles of soil is easily done in our minds. The result is when ammonia stings our noses, we sympathize with the field we are fertilizing. After all, there is no worse label than a "harsh chemical".
Not much objective evidence to support this lovely picture, however. Indeed after using NH3 and other fertilizers for decades, yields are trending up, not down.
Due to the chemistry of anhydrous ammonia, the injection band initially is toxic to plant growth because of high pH. In a relatively short period of time after injection into the soil the ammonia is converted to nitrate and the pH of the injection band decreases. Nitrate is the primary form of nitrogen used by corn from the soil. At this point the corn plant can use the fertilizer and provide higher yields. [More]Much of the allure of agrarian agriculture is the elevation of clay particles to some kind of life-form. Because life (plants) spring from it, it is an easy step to take. In the process, however, we attach limitations and rules that may or may not apply.
The soil is "exhausted", we say, as if dirt feels weariness. We talk of soil "health". Qualities we find pleasing, like sponginess or rich odors are designated as signs of soil "health". Moreover, as we develop more and more abstruse technologies, the idea of soil as simple and uncomplicated is a relief. But I'm convinced we are fooling ourselves.
I don't think we have any idea what the "carrying capacity" for good farmland is, for example. All we know is how much yield we have been able to achieve to date. I think we will look back on 200-bushel corn with the amusement we now use for pre-hybrid corn yields.
And people then will mutter about exhausting the soil, I expect. But soil is not human, and not even alive. And the effort to make this fantasy true is our generation's form of idol-worship, maybe.