Principles of Soil Health
Did you know that one or two teaspoons of soils contains more organisms than there are people on planet Earth? It is almost hard to comprehend that the life beneath our feet is made up of a complex interwoven web of carbon based organisms that support and feed the plants, trees, and shrubs we see above ground in our landscapes. But that is exactly what is happening. The soil food web starts with the liquid carbon pathway, which is better known as photosynthesis. The sun’s light is absorbed by plant tissue and CO2 is absorbed through the plant’s stomata, harvesting both the light and gas to produce sugar to feed itself. But that is not the end of the story. Plants also need essential elemental nutrients from the soil. To get these nutrients, plants send the excess sugars out through their roots in the form of exudates, feeding soil organisms such as bacteria, fungi, and protozoa. The microbial organisms in turn provide food for each other and the higher forms of life such as nematodes, micro and macro invertebrates, worms, insects, birds, and mammals (as seen in figure 1). The food web cycles the carbon in these organisms until eventually it is stabilized as hummus, completing the liquid carbon pathway! Every land management decision we make has the potential to either foster or degrade the soil food web. If we think about these basic principles before we make decisions on the land, we will help foster the soil food web which in turn will keep our plants and soils healthy.
“…the Latin name for man, homo, derived from humus, the stuff of life in the soil.”
—Dr. Daniel Hillel
“To see a world in a grain of sand and a heaven in a wildflower.”
—William Blake, Auguries of Innocence