Organic Soil Management

1. Organic Soil Management The purpose of soil management is to nourish soil organisms so they can build soil structure and cycle nutrients.

2. Soil Components

3. Mineral component • Sand – largest O 20-40x • Silt – medium o 25x • Clay – smallest . 1 • Pore space varies with size of particles

4. Soil textures

5. Characteristics of the Various Soil Classes

6. pH • pH is the measure of the concentration of hydrogen ions. • It is measure on a logarithmic scale going from 1-14 with 1 being the most acidic (most hydrogen ions) and 14 the most basic (least hydrogen ions). • pH of soil is important because certain chemical reactions only occur in certain range. • Not as important for organic systems, because they depend on biological reactions, not chemical reactions.

7. Soil Ecosystem • Biological model of soil management as opposed to the chemical model is the major key to good soil management. • More individual life forms in soil than live on the surface of the earth. • 4 billion bacteria, 1 million fungi per teaspoon of soil • Perform many functions to support plant life

8. Biodiversity • Soil fertility is related to having a large number of different types of life forms. • Different crops depend on different ecosystems. • Annual field crops – bacteria dominated • Woody perennials – fungi dominated

9. Producers-herbivores-predators-higher predators-decomposers

10. How the soil food web benefits plant life • Builds soil structure • Disease suppression • Improves nitrogen retention • Mineralizes nutrients • Produces plant growth hormones • Improves crop quality

11. Factors to be managed • Soil air Greatest • Soil water • Soil organic matter • Soil minerals Least Plant response

12. Soil air management • Most important because beneficial soil organisms need oxygen to live. • Anaerobic organisms produce plant toxins and bad smells. • Plants also need oxygen in the soil for nutrient uptake and for growth of the roots.

13. Soil air management • Most important because beneficial soil organisms need oxygen to live. • Anaerobic organisms produce plant toxins and bad smells. • Plants also need oxygen in the soil for nutrient uptake and for growth of the roots.

14. Soil Water Management • All living organisms need water to survive. • Too much or too little water can kill.

15. Managing soil water • Primary technique is tillage – to create pore space • Optimum soil water content is 20-30% but it will fluctuate with rain and/or irrigation • Monitor soil moisture with moisture meter or visual examination • Different areas will have different moisture levels

16. Soil organic matter • Made up of living and dead residues in different stages of decomposition (living, dead and long dead) • Food source for the decomposers who feed on dead organisms and waste products

17. Conserving soil organic matter • Avoid excess tillage • Retain crop residue • Cover crops

18. Managing soil organic matter • Two ways: • Conserve existing organic matter • Adding organic matter to soil

19. Adding organic matter to soil • Raw manure • Organic standards considerations • 120 days for root crops • 90 days for other crops • Compost • Requires a large amount • Must have source of materials to compost • Must be gathered

20. Soil mineral management • Least effect on crop production • Good management leads to better plant health, higher nutritional quality, increasedflavor and shelf life • Especially important in SE US because soils have been depleted – long warm season with abundant rain – higher rates of reactions in the soil, rapidly leached out of soil N P K S Ca Mg Fe Cu

21. Managing soil minerals • Primary technique is a soil test • Analysis of test • How to Convert an Inorganic • Fertility Recommendation to an Organic One