Recently our CEO, Pamela Berstler, spoke in a meeting of Water Conservation Managers noting the paramount importance of educating about soil health in water conservation and pollution prevention. Pamela argued that building a healthy, biologically active Soil Sponge was the MOST IMPORTANT ACTIVITY in healthy landscape building and that this truth applied to all manner of land use from agriculture to urban/suburban residential and commercial, parklands, and even “natural” watershed areas that we would consider wildlands. Pamela also reasoned that all soil is degraded (especially biologically speaking) and that intervention, remediation, and ACTION was required to rebuild our soils, particularly as it applies to garden-building, even when using plants that are considered native or have become perfectly adapted to the climate and place over thousands of years.
There was push-back from the audience. One attendee proposed that plant selection and placement was the most important factor for education and that selecting and planting native plants in native soil was THE simple and compelling solution for restoring watersheds and producing healthy, low resource gardens (including water conserving, of course). The reasoning was that native plants don’t need soils with organic matter in them, and so long as the microclimate conditions supported the plant selection, no soil amendment was necessary.
On the surface it sounds right, especially when Southern California wildlands are observed — it doesn’t look like there is anything special going on. SoCal soils appear to be lean. It is a semi-arid mediterranean climate. The native soil appears to be devoid of both nutrient and organic matter. Certainly a chemical assay shows low Nitrogen, Phosphorous, K (Potassium). And the native plant ecology appears to be loving the land just as it is — no inputs whatsoever of either organic matter or biological agents.
But look closer in nature and look at the supporting science. This picture requires that you look not just with your eyes, but with your microscope too. Look at the base of the manzanita or ceanothus in a wildland setting. Look at the grasses and the buckwheat, and the sage. Each plant has created its own soil remediation strategy right at its rootzone. It’s last season’s leaves have been dropped at its feet, and its roots have exuded the exudates necessary to call the micro and macrobiology in the soil to come and decompose this organic feast. The recent rains filled tiny micropores between rootzones, and the sleepy microbes (bacteria, protozoa, nematodes, and fungi) have awakened, ready to eat. It’s a good thing they are now awake, because this cooler, rainy season is when the plants, having adapted to the local climate, are ready to power up their life cycle to grow, flower and fruit. They are calling upon the microbes to attend to their needs. They will need a soil party, and it had better be a big, diverse, rockin’ one!
The story of garden LIFE is an integrated story. Chemistry alone does not explain why plants live and die or why water fills the soil or runs off. Physics alone does not explain these processes. Bio-chemical-physics is necessary for the full explanation. Biology is the required, central, predominant puzzle piece in the explanation of how the plant/soil/water relationship works.
As native soil and the ecology it supports are degraded through processes mostly human-influenced including (but not limited to) prolonged drought, air pollution, over-irrigation or over-fertilization, desertification, and disturbances like fire, or even hiking, the plant/soil/water relationship shifts. Grasslands become dominated by woody plants/trees. Trees collapse and grasslands or deserts develop. Each particular ecological cycle is determined by the microbial population in the soil, which too has developed over millennia in perfect symbiosis with the parent rock, weather, plants and animals of the site. The microbial population is healthy when there is Oxygen, Water, and Life-supporting food (organic matter). Where there is Living Soil, there is plant life. And so it is the Living Soil that determines the type of plant community as well as the hydrology of the site.
Now apply this wondrously complex intersectional relationship to ALL SOIL, even garden soil. When we are managing an urban/suburban or severely degraded setting such as a deforested and desertified grazing land, or eroded park, burned-out wildland interface, or turf-covered, over-irrigated lawn or compacted site on which a building or road has been made, what lessons should we learn from the native environment? The list of possible degenerative activities gets longer the closer you move toward human intervention. And so, the regenerative techniques required to preserve or build this singularly precious material, the Living Soil of the Earth, must become more diverse, more cunning and more universally applied.
The story of watershed regeneration and landscape health is not a story that is over in one short blog post, or even a lifetime of dialogue. This is not a story that is told in bullet points or that doesn’t have twists, turns and dead ends. It is a story of exploration, observation, and science. The story of watershed regeneration is a story of miraculous complexity starting with the tiniest creatures, only visible to the electron-scanning microscope-assisted eye, that, once invited into the rootzone of the plant by the plant itself, and provided with plentiful oxygen, water, and food, will sequester the carbon, store the water, decompose rock and organic matter, convert it to nutrient, and provide it to the plants in the ecosystem when (AND ONLY WHEN) the plant asks to be fed. Even describing the process in language as simple as possible creates a runon sentence.
The lesson for those in G3 is: Protect and nurture your O.W.L. (Oxygen, Water, and Life), because Living Soil is the KEY FACTOR in environmental health in general and specifically for the health of your landscape and the health of your waterways.
But it’s a place to start.