Restorative Soil Techniques: Creating Healthy Soil

The true wealth of a nation is in its forests and the soil.   Healthy soil builds healthy people; the vitality of the food that nourishes us is directly related to the richness of nutrients in the soil.  Soil performs many other vital functions such as: housing important organisms and microorganisms necessary for decomposition and fixing nitrogen; filtering underground water; and providing material for natural building.

Soil can be degraded in three different ways: physical, chemical, or biological, causing reduction in soil vigor; reduction in soil volume and mass from erosion; and accumulation of detrimental soil chemicals such as salts (causing salinity), hydrogen ions (causing acidification), and industrial chemicals.[3]  Humans are the main cause of worldwide degradation of our soils. The two major human-induced causes of soil degradation world-wide are water erosion and removing vegetation for agricultural purposes, cattle raising, urban development, large-scale commercial forestry, etc.[4] Other human actions that degrade our soils include:  unsustainable development; improper waste treatment and other forms of pollution; mining for raw materials; and destructive management practices of agricultural land such as excessive chemical fertilizing, lack of anti-erosion measures, use of pesticides, etc.

DEVELOPING SUCCESSFUL SOIL RESTORATION PLANS

Soil originated from bare rock and took millions of years to come into existence.  Soil formation is heavily influenced by climate, thus soils from different climatic zones have unique characteristics that help instruct us when developing soil restoration plans.  Tropical climates have higher temperatures and rainfall, contributing to leached soils that tend to have lower nutrient concentrations than temperate or arid climates.

The reserve of soil nutrients that is found in soil lies in the top few inches called the humus layer, which is a very stable layer of organic matter that is left after plants and animals decompose. In rainforests, the majority of the nutrients are not found in the soil; they are concentrated in the incredibly lush vegetation above the soil. This is yet another reason that it is so devastating when we clear cut rainforest vegetation and forests, because we are not only stripping the vegetation, we are stripping the majority of nutrients from the area and in turn, making it extremely difficult for the soil to recover and provide a rich growing environment in the future. 

The best way to increase the health of vegetation and resistance to pests and disease is to build the soil.  The fist step in building healthy soil is to practice no-till farming, which leaves beneficial fungal mycelium intact, increases water retention, unlocks natural nutrients in the soil and reduces erosion.  Depending on the unique set of problems we need to address, we also rely on the following simple techniques to regenerate soil:

• Soil Testing:  We utilize numerous tests to determine soil nutrient content, structure and pH to aid us in determining tailored solutions for ideal plant growth.
• Dynamic Accumulators: We incorporate these deep tap-rooted plants into planting schemes because their roots mine for nutrients deep in the soil, bringing banked nutrients up to the top of the soil.  These plants also provide nutrient-rich matter when added to composts, or directly to the soil when they are chopped and dropped right where they grow.
• Chop and Drop:  Planting cover crops, and cutting and let lay is a technique that helps to build nutrient-stripped soil faster than letting vegetation die through its natural process. 
• Planting Trees:  Tree roots go down into the subsoil much further than most other vegetation and they make their nutrients available at a number of different levels, from evaporation from their leaves down to the bottommost layers of the top soil and beyond.
• Nitrogen Fixers: Cover crops from the legume family whose roots are colonized by certain bacteria that extract nitrogen from the air and convert atmospheric nitrogen or "fix it" into a form that plants can use. Promotes plant growth and healthy soil in nitrogen deficient conditions.
• Carbon:  Incorporating the appropriate amount of carbonaceous material, enables the soil to drive the decomposition process in a clean, healthy way. 
• Natural Fertilizers:  We are testing a variety of bacteria rich natural fertilizers from kitchen composts and special plant blends. Coordinating soil regeneration plans with use of natural fertilizers benefits both the vegetation and the soil.
• Earthworms:  Increasing earthworms means more worm castings, which are good for adding phosphorous and calcium to the soil as needed.  Ants and termites provide a similar service in the tropics.
• Earthworks: Reducing runoff throughout growing sites and saving any topsoil excavated from building earthworks preserves soil for use in garden areas that need additional topsoil.
• Allelopathy:  We avoid certain allelopathic intereactions to discourage the inhibition of growth of beneficial vegetation by plants releasing biomolecules called allelochemicals that inhibit the growth of neighboring vegetation.