Owen Gudeman

Nutrient Cycling Start: OM and Residues 1️⃣ Microbes release enzymes to break long chain carbons of OM and residues into smaller, soluble carbon compounds. The water-extractable portion is what we measure as WEOC. 2️⃣ This breakdown also releases nutrients from the residue, but not all are immediately plant-available. 3️⃣ Microbes consume WEOC for energy and consume (immobilize) nutrients to live on. This causes the microbes to grow and multiply. 4️⃣ Microbes release (mineralize) nutrients when their nutrient supply exceeds their needs. Nutrients are also recycled as microbes turn over and are grazed. 5️⃣ These nutrients are now plant-available, though they don't stay put for long (everything moves in the cycle). Plants use them to build tissue and photosynthesize, then release some of that fixed carbon through their roots as exudates, adding to the soluble carbon pool we measure as WEOC. Why does this matter? Building and managing WEOC supports a more efficient soil system, with active microbes cycling carbon and nutrients, and can reduce dependence on synthetic inputs over time. Residue management is part of the equation as well as encouraging microbial activity season-long. *this is extremely simplified and there is a lot that goes into this cycle. But this is how I think through nutrient cycling at a basic level.

Sat down with some growers yesterday to go over soil samples from 2024. I thought this one was interesting. This guy has his base saturations nearly perfect. Guess how many years it took him to build and balance them like this? None. Well actually it took him NOT applying MAP, Potash, or Lime for 5 years. What he does do is feed the plant in season. Plant health=healthy (i.e. functioning) soil. By creating healthy plants, this grower has “balanced” his soil and also has pH where the industry would want it. I don’t necessarily feel that that is the goal. The goal is to have nutrition available to the plant when the plant actually needs it. How do we move nutrition from an unavailable form in the soil to an available form? Biological activity which is predicated on WEOC. What gets missed if we only focus on base saturations and hitting ppm values is that this guy had great WEOC, biological activity, and aggregate stability. What’s the point of this? Maybe we’re after the wrong things when we attempt to “build” the soil. Soil is resilient if we’ll only let it be. I heard the quote recently, “we want to let the soil farm for us, and not us farm the soil.” That’s what’s happening in the scenario I just described. And none of this means I’m anti-fertilizer, but I am against being inefficient.