Grow Soil, Not Plants © 2010 - 2011 by C. Darren Butler Do not publish or distribute without permission Note to Master Gardeners Thanks for attending my talk at the 2011 Statewide MG Conference. This version doesn’t include images for which I don’t (or may not) have the rights to publish. The scientific information is widely available and much of it is based on Elaine Ingham’s work, so please credit her when appropriate. The approaches, philosophy, phrasing, and almost everything else are my work, so please credit me if quoting or referring to them. Photos with no credit are my own. Portions of this material are expected to appear in books and/or articles. This is for your use and reference only; please do not republish or distribute without permission. It was a pleasure getting to know many of you and I look forward to reconnecting when we have a chance. Please feel free to contact me but be patient with response time and try again if you don’t hear back within a week or so. Let’s start with . A QUIZ Image Credit; www.Discoveryschool.com By Mark A. Hicks How do we think about dirt? What comes to mind first about dirt? Did anyone say . • The fundamental system upon which all terrestrial life and all of our lives depend? • The foundation of all civilization? • An unimaginably vast reservoir for the building blocks of life and our shared lifeforce, and for life itself in all of its conflict, interactions, death, and rebirth? • Us? Our bodies are soil in temporary human form. Let’s imagine . • A floating ball with a magical gooey surface • Unique living organisms constantly rise up from the goo and fold back into the goo • With an endless variety of species and individuals • In which all the living organisms are interrelated and mutually interdependent • This describes Earth • The magical goo is soil Is soil more biotic or more abiotic? Is soil biotic or abiotic? • If you are the California public school system, apparently it is abiotic, like a brick. • For almost everyone else, especially gardeners, soil is biotic, like us. Which are there more of in soils, bacteria or fungi? Photo credit: zakwitnij/flickr Photo credit: byr105063/flickr Are there more bacteria or fungi in soil? • It depends: bacterially and fungally dominant soils • Ratios of bacteria/fungi indicate what is growing or what will grow well aboveground • Grasslands, garden, and agriculture soils bacterially dominant • 1:1 ratio in gardens/agricultural soils, less fungi possible • Forest soils fungally dominant • 5:1 to 10:1 fungi to bacterial in deciduous forests and up to 1000:1 in coniferous forests • Soil succession Name five kinds of soil microorganisms. Soil Microorganisms • Bacteria • Actinomycetes • Fungi and Mycorrhizal Fungi • Algae • Protozoa • Nematodes Name five kinds of soil macroorganisms. Soil Macroorganisms • Earthworms and other worms • Arthropods (insects, arachnids, crustaceans, springtails) • Gastropods (slugs and snails) • Reptiles and amphibians (lizards, snakes, toads, salamanders) • Mammals (mice, bunnies, ground squirrels, gophers) Feelin the Blank Healthy soil will contain _____ pounds of belowground life per acre. 7240+ pounds • Several pounds of mammals. • 133 pounds of protozoa. • 900 pounds of earthworms. • 900 pounds of arthropods. • 900 pounds of algae. • 2000 pounds of bacteria. • 2400 pounds of fungi. (Doesn’t include some kinds of soil life, such as nematodes.) Source: Teaming with Microbes, Lowenfels and Lewis, from Elaine Ingham’s research. Living Systems: • Biological systems comprised of many kinds of organisms including plants, animals, bacteria, and fungi in an interconnected web that is dependent upon and cycles resources such as food, energy, and water What is accomplished by living systems that depend on soil? What is accomplished by living systems that depend on soil? • Capturing of sunlight and recycling of nutrients to allow the vast abundance and complexity of life on Earth • Production of food for uncountable terrestrial organisms. Some estimates are of 1018 (one quintillion) individual arthropods and 10100 (one googol) total individuals of all species on Earth) • How much have we thought about how amazing it is that Earth’s systems produce food, habitat, and other needs of all life on the planet?) • Providing habitat and useful materials for all species • Creating mutually support systems (food web, environmental, chemical, etc.) for using resources and maintaining life (Nature conserves species, not individuals) • Processing waste/returning to resource What is accomplished by living systems that depend on soil? • Ecological succession: moonscape to old-growth forest • Provide ecological balance with predation, pests and diseases and control of predation, pests and diseases • Death-based vs. life-based gardening, landscaping, agriculture, and cultural systems • The unimaginably vast natural systems on Earth provide each of us everything we love (the 3 degrees of interdependence) • And much more Defending our Soil . doesn’t require guns. Landscape living systems start with soil. Trophic level = number of steps from the start of the food chain. My Biases • Life-based rather than death-based • Use living systems (Why do we perpetuate death-based systems?) • Focus on soil • Low tech with minimum inputs (vs. plastic-crap gardening) • Natural and human efficiencies • Achieve goals by observing and cooperating with natural systems rather than battling them Compare infertile, dead clay soil . to loamy, living soil. SOIL • The place of death and rebirth in landscapes; where sunlight is removed from organic matter (decomposition) so molecules can return to new life as part of another organism • Microscopic transformation: everything turning into everything else; everything eating and being eaten • Healthy soil is dynamic, full of life and millions of ongoing interactions we can’t see • Our bodies are soil in temporary human format; our bodies contain stardust, recycled molecules from the entire myriad history and fullness of life on Earth SOIL • Powered by organic matter • Contains/stores nutrients and water • Habitat for micro and macroorganisms • Provides air to plant and tree roots • Holds seedbank (not just weed seeds) • Healthy soil ecologies mitigate plant and tree diseases, provide nutrients to plants in exactly the form and amounts that are best for plants • In healthy landscape systems, soil ecologies are determined by plant exudates (plants are in control) How do living soil systems and good soil structure improve plant health? • Microbes communicate with plants and take care of their needs on cell-by-cell basis and at a microscopic level much better than we can (mutualism for water, nutrients, preventing uptake of toxic metals) • Decomposition and elimination of unsuitable individuals • Oxygen and nutrients more available • Creation of habitat for further soil life • Biodiversity in soils provides natural control for pathogens and pests (competition, predation, diseases for pests) Photo Credit: Meg Glasser Photo Credit: Meg Glasser Photo Credit: Meg Glasser Photo Credit: Jessica Nešič How does healthy soil increase sustainability • Local microbes may have evolved for thousands or millions of years to suit the exact local conditions and fulfill exact local needs • Reduce inputs/outputs because fertilizer needs met by the soil; soil life is fertilizer in healthy soils • Reduce or eliminate need for disease and pest treatment • Increase yields • Bacteria and other soil life function as rain cisterns How does healthy soil increase sustainability • Healthy soil a foundation for resilient human communities • Hold nutrients for next generations of human and other life • Living soil systems integrate with larger bioregional food web, watershed, and climate systems • Soil living systems co-evolve with aboveground life as an ecosystem matures, becomes more complex and resilient What Lives in the Soil to Create Living Soil Systems? Soil Life • Bacteria • Actinomycetes • Fungi and Mycorrhizal Fungi • Algae • Protozoa • Nematodes • Earthworms • Arthropods • Mammals Microorganisms • 7 billion living organisms per handful of fertile soil • In healthy ecosystems, they coat every part of the plant or tree and prevent access by pathogens • Fragile, specialized • Compaction/anaerobic bacteria • Decomposers • Are themselves food • Hold nutrients; in healthy soils, the soil life itself is fertilizer (especially Nitrogen) • Store water that is released under stress • Fulfill broad array of functions • 95%+ aren’t harmful to humans, plants, landscapes Bacteria (2000x) (and algae) Photo Source: SecretDisc/Wikimedia Bacteria (5000x) (and algae) Photo Source: SecretDisc/Wikimedia Bacteria • Earliest known form of life on earth • Decomposers • Food source for protozoa, nematodes, earthworms, and other organisms • Wide range of functions in soil • Early succession soil (alkaline) • Unable to break down complex, woody materials • 4,000 to 10,000+ species in a given area of soil • Source of nitrogen in healthy soils • Store water and provide to plants by dying when soil ecosystem is stressed Actinomycetes Photo Source: CDC/public domain Actinomycetes Photo Source: CDC/public domain Actinomycetes • Eubacteria that act like fungi, forming filaments and spore-like bodies • Decomposers • Produce the “earthy” odor of compost and rich soil • Capture N from air to form ammonium (soil-available nitrogen) Mycorrhizal Fungi Photo Source: Flickr/AJC1 Arbuscular Endomycorrhiza (penetrates cells of vascular plants) Photo Source: public domain Fungi