Despite the best efforts of soil health advocates, the rate of synthetic fertilizer use is still on the rise. According to USDA, in 1964, farmers were applying on average 58 pounds of nitrogen per acre. By 2010, the average was 140 pounds. It’s unlikely those numbers have changed much since 2010, and that level of nitrogen certainly has ramifications on insect control, environmental runoff and soil fertility.
Nitrogen is everywhere – in our bodies, in plants and animals, in the soil under our feet. The vast majority of the planet’s nitrogen is in the atmosphere. The air that you breathe is about 78% nitrogen, but it’s not in a form that plants can use, such as nitrate (NO3) and ammonium (NH4).
Without nitrogen, plants wouldn’t survive. And no plants, no humans.
How do we get nitrogen for our plants?
- Atmospheric Fixation – lightning strikes break the bonds of the molecular nitrogen, N2, in the atmosphere. The result: thunderstorms fertilize our farms.
- Biological Fixation – Microbes in the soil convert atmospheric N2 into plant-available forms. Once this occurs, it’s cycled through the food chain via consumption and decomposition.
- Industrial Fixation – German chemist Fritz Haber (also the father of chemical warfare) figured out how to convert atmospheric nitrogen into ammonia (NH3) or synthetic nitrogen.
Okay, what’s the big deal anyway? Well, synthetic nitrogen fertilizer destroys the carbon and nitrogen storage and cycling capacity of your soil. That’s the system of biological lifeforms in the soil that make nutrients available to the plants – fungi, bacteria, nematodes, arthropods, etc. Plants, in turn, feed the lifeforms carbohydrates via exudation from photosynthesis. When you add synthetic nitrogen, existing carbon and soil nutrients disappear. Rather than storing carbon, carbon stores are released into the atmosphere.
This is the reason why over the past 40 years, nitrogen fertilizer efficiency (the rate in which plants can use nitrogen fertilizer) had decreased by two-thirds while nitrogen fertilizer use per hectare of land has increased sevenfold! The increase in nitrogen use has far-reaching ramifications — for example, the poisoning of the world’s water supply.
Synthetic nitrogen fertilizer also increases plant pathogens and insect pressure. Plants grown in degraded soil without beneficial symbiont microorganisms present to protect and feed them will develop macro- and micronutrient deficiencies. Frankly, this is how glyphosates work; inhibiting the absorption of trace elements weakens the plant and then once-symbiotic microbes turn on the host plant and begin to devour it.. Weakened plants invite unwanted guests.
Fifty years of research indentified 135 studies showing more plant damage and/or a greater number of leaf-chewing insects or mites in nitrogen-fertilized crops, while fewer than 50 studies reported less pest damage. Researchers have demonstrated that high nitrogen levels in plant tissue can decrease resistance and increase susceptibility to pest attack.
I believe that we may look back on the introduction of synthetic products, or at least the vast amounts of it, into our farming practices with regret. In the 1950s advertisements promoted the regular use of DDT. Seemed fine at the time, but today it’s considered so short-sighted and harmful.
Andaman Ag carries a host of products, for both foliar spray and fertigation applications that promotes increased soil fertility coupled with naturally occurring nitrogen inputs.