Don’t overthink your soil biology writes Andrew McGuire in a blog post with that title. I recommend you read the entire article. I’ll include a few quotes here.
He notes three common errors around soil biology.
“First, an over-inflated idea of the size of soil biology benefits. Second, the assumption that our soils have soil biology problems. And finally, to fix the problems, an increased susceptibility to unproven products or practices.”
“And in most cases, the “problems” are not actually problems. A few proven practices will often do.”
“Here is what you need to know about soil biodiversity. First, diversity itself does nothing. Rather than being an actual mechanism or cause—think pH, soil structure, disturbance, etc.—biodiversity is only correlated with mechanisms. It is not the cause of soil function, and therefore not so helpful in determining management.”
“Another perceived problem is that you don’t have enough soil microorganisms. Here, remember that the amount of life in your soil is directly related to the amount of food and habitat available.”
“Most of these “problems” are not problems, and if they were, would not be easily managed. Even the detection of these “problems” is problematic. Many of our measurements of microbial characteristics, including microbial biomass fungal:bacterial ratio, enzyme activities and ratios, mycorrhizal abundance/composition and C and N mineralization rates are not necessarily representative of the actual soil function or are not easily interpreted.”
“Rather than practices that give inconsistent results such as compost tea, inoculations, or home brews, might it be better to focus on improving your soil’s physical environment, protect your improvements, and let the microbes do their thing? You are the driver. Where do you want to go?”
For more imaginary problems, see this from Frank Rossi about calcium deficiency.