Kyle Grotelueschen

A 200 bushel corn crop is built mostly from air and water. Does fertility play a role? Of course. But thinking of crop production in terms of photosynthesis changes how we think of increasing productivity. If we were to burn up a crop, ~95% of its weight would be carbon, hydrogen, and oxygen which would escape as a gas. Only ~5% comes from the soil: N, P, K, Ca, Mg, S, micros. These would be left as ash. The 95% enters the equation through photosynthesis. 6 CO₂ + 6 H₂O + light → C₆H₁₂O₆ + 6 O₂ One sugar and six O₂ are what we end up with. And that Glucose is the currency the plant builds everything else with. Everything we get as a byproduct of this is just glucose rearranged: •Starch •Cellulose •Oils •Waxes •Lignin •Protein And this protein averages ~16% nitrogen. Even the crop’s nitrogen story runs through carbon fixed in the leaf first. The photosynthetic engine is built from nutrients. Consider further: Chlorophyll is one magnesium atom held in a ring of four nitrogens. No Mg, no N → no chlorophyll → no photosynthesis. The 5% from the soil helps build the machine that captures the 95%. Even the roots run on this sugar. Root growth, nutrient uptake, and metabolism are all powered by photosynthates sent from the canopy. When photosynthesis is capped or stalled, root function does the same. Why does any of this mean anything? When we capture more sunlight and more CO₂ per acre, the more we preserve the plant’s potential. Fertility really just keeps the machine running so the crop can produce at a higher potential. One caveat on CO₂: •C3 crops (soybeans, wheat) gain ~13–18% yield under elevated CO₂. •Corn is C4, and with good moisture it barely responds to elevated CO₂. The only time when gains have shown up in these conditions is mostly under drought. As crops are headed toward maturity, it is still important to consider what drives functionality. In our nutritional and fungicide passes left, how can we capture the 95%?