CompostCourses/WorkshopsFungiSoil BiologySoil ConservationSoil Rehabilitation

Soil Food Web Course with Dr. Elaine Ingham

October 30 – November 1, 2009
Orella Ranch, Gaviota Coast, California.

A wise person once said that soil is not only more complex than we know, it is more complex than we can ever know! The good news is humans have lately achieved a level of practically applicable knowledge and experience in soil biology to be absolutely capable of massive, positive impacts on sustainable soil use world-wide! It is undoubtedly true that we’ll never know everything, but no matter – we already know enough to get very, very busy!

Renowned microbiologist Dr. Elaine Ingham kicked off the West coast leg of the first-of-its-kind Carbon Economy Course with a powerful three-day learning-fest centered on the soil food web. The bionics of biology, miracles of super-charged soils, blessings of extra-strength compost, and explosive results of super-activated compost teas were all on abundant offer in this powerful course. Such topics sparked a highly-charged, enlivening energy in the ‘brain-food-web’ of the attending students, while setting an inspired tone for the modules to follow in the series!

Thirty seven enthusiastic soil nerds, garden-geeks, and other ecologically minded farmers, permaculturists, and assorted agrarian adventurers from all over the US and beyond (many from all parts of California, Colorado and as far as Vermont) converged at the beautiful Orella Ranch for a full complement of complex food web inter-dynamics, mind-blowing biological success stories, rigorous scientific data, and no shortage of classic, coastal California sunsets overlooking the rippling Pacific (this radiance was rivaled only by the continual ‘light-bulbs’ popping on above the heads of the students in class!).

Orella Ranch, California coast

Dr. Ingham is President and Director of Research of Soil Food Web, Inc.; a successful commercial lab (with locations in Australia, Canada, South Africa and the US) which analyses soil and tea samples for their clientele, as well as providing consultation on using biology to vastly increase soil and plant health and promote a sustainable permanent agriculture. Clients include everyone from backyard gardeners to ranchers to 5,000 hectare farms and beyond (SFW, Inc. has worked with growers on over 2 million acres). A prolific author of cutting-edge research in the area of soil biology, Dr. Ingham is also a very engaging speaker and energetic teacher who is never more excited than when sharing her wealth of knowledge with students in the courses she offers regularly.

Talk about “Care of EARTH!” Most would agree this first of the Permaculture ethics begins quite literally with the small ‘e’ earth itself; soil. In this spirit, the Orella SFW course started off with a detailed introduction to the massive variety of soil organisms, from bacteria and fungi, through protozoans and nematodes, and on through the food web into micro and macro-arthopods and earthworms (An excellent condensed introduction to these can be found in Dr. Ingham’s Soil Biology Primer—a USDA publication). Along the way students learned about how the various organisms function in soils to:

  • produce good soil structure
  • cycle various nutrients (nitrogen, sulfur, phosphorous, etc.) and make them available to plants
  • interact with each other and with the root zones of plants
  • provide nutrition to plants in the right places, at the right times and in the right amounts
  • improve water holding capacity and aeration
  • reduce compaction
  • eliminate any need for pesticides or inorganic fertilizers
  • greatly reduce water use (often, up to 70% reductions)
  • increase both plant yields and topsoil

All of this, along with much more learning–about the affects of aerobic vs. anaerobic soil conditions, bacterial to fungal biomass ratios in the various ecosystems of the world, as well as the steps needed to move from a conventional industrial farming model to a biological and sustainable one—was only the first half!

Next, Dr. Ingham took the increasingly energized class through a detailed and well researched explanation of creating lively composts, brimming with the good biology needed in the soils and by the plants. This included different recipes for different scales and contexts, ways to tilt your composts towards bacterial or fungal dominance depending on your needs, as well as worm-composts and general vermiculture.

Finally the course dug into the topic of using good composts to brew excellent compost teas! From teas to extracts and soil drenches, Dr. Ingham took the class through the process, explaining how to best get life—and the precise life that you want–exploding in your tea bucket, vat, or tank, and from there out into your soil, or onto your plants. In the process students were exposed to amazing slides and explanations of the various and fascinating forms of life we want to see and identify in our teas and extracts when sampling them under the microscope. By course end, having been very well ‘inoculated’ and ‘activated’ with this valuable information, everyone was itching to get brewing!

A few additional ‘light-bulb’ sparking tidbits from this excellent course:

  • There is life in soils as deep down into the earth’s core as humans have sampled—16 miles! There are even bacteria adapted to a habitat of molten lava!
  • Organic matter holds TEN TIMES its weight in water, and there is no upper limit to the amount of organic matter a soil can hold! 100% not impossible.
  • A healthy soil will have 50,000 protozoa per gram/teaspoon. These will collectively eat 500 million bacteria (per gram) every day (about 10,000 bacteria per protozoan), releasing 400 million molecules of Nitrogen (per gram, per day), typically right in the root zone!
  • Standard soil tests measure only 1% of the total pool of soil nutrient (which is the ‘soluble fraction’ existing precisely at the time of sampling). This 1% fraction gives no information about the rate of nutrient cycling and replenishment provided by the soil biology from the remaining fraction. There is, therefore, no relationship – zero – between the numbers these standard lab tests will give you and the nutrients that end up in your plants! With the right biology in your soils plants will tend to have access to all major nutritional needs regardless of ‘low’ soluble fractions shown on standard lab tests.
  • Using good soil biology can even eliminate the need for the very ancient practice of crop rotation! No disease, no need to rotate. Continual nutrient supply, no need to rotate. Therefore, one need never till again, saving time, energy and money, while increasing surplus topsoil, yields and other profit margins!
  • Who doesn’t like CHOCOLATE! A well made, finished compost – likely to have all the ‘good guy’ food-web organisms we want – can be COLOR checked against a 70% cocoa chocolate bar. That is the ideal color we want to aim for in our composts and even topsoils. Check it out and enjoy!

Thank you, Dr. Ingham, for your tireless efforts and kudos to the good folks at Quail Springs and Orella Ranch who are jointly organizing and convening this leading-edge series. Congratulations on a very successful start! See the links to these organizations to learn more or to donate in support of their ongoing efforts to bring sustainable land management practices to a wider audience. Also, see the Soil Food Web, Inc. website for updates on future SFW courses or to purchase Dr. Ingham’s books or lectures (on cd) and learn even more of this fascinating and powerful information.

Next up in the Orella hosted West coast Carbon Economy Series: Sustainable Land Management with Kirk Gadzia (Holistic Management – Resource Management Services) and Darren Doherty (Keyline Design, Broadacre Permaculture – ). See you there!

Owen Hablutzel performs international work in Permaculture design, consultation, speaking, and education. He is a director of the Permaculture Research Institute, USA, and can be reached at owen (at)


  1. Thanks for this update Owen. Please keep us abreast of the other course modules as they run. It’s an outstanding series and there are many people following this initiative with great interest. Especially for those of us unable to attend this round of CFCs, your reports and photos are a great inspiration!

  2. Great article Owen! We met at Geoff Lawton’s 2008 PDC at Quail Springs. I live in Mexico. Dr. Ingham’s biological approach popped the top of my head off when I first heard it. I wish every permaculturalist could learn from her. Its taken my sustainable/regenerative agricultural work to a completely new level. In case you’re interested this summer I combined permaculture rainwater harvesting techniques with the Soil Foodweb approach growing corn in Mexico. Dr. Ingham and Matt Slaughter, Director of the Oregon Soil Foodweb Lab gave me invaluable consultations on applying the approach to the corn.

    The 2009 summer in Mexico has had worst grought in 68 years. Most dryland corn in Mexico has died or is extremely stunted and non-productive, stressed stalks plagued with worm bores. The results with the Soil Foodweb aprroach have been quite dramatic. Here’s a link to my website in case you want to take a look. The second article on my site has a link to my initial corn results. Its a rough presentation doc without a lot of explanation. I’m right in the middle of the corn harvest (yields look great) and will be doing a video that should be on my website in a couple of months with More details and a background story. Permaculture folks might be interested to know that the swales in the corn field are a first year drylands food forest. We’ve planted over 120 backbone rhizobia Nitrogen-fixing native trees and some nut and fruit trees – next year a lot more. Since the corn and forested swales need a different bacterial:fungi soil ratio I’m using different aerated compost teas, fungal foods, woody much and fungal composts to create an ‘island’ of fungal dominance in the swale rows while maintaining a more even split of bacteria to fungi in the adjacent corn field. Thanks for the great article. I hope more permaculturalists learn about the incredible possibilities of Dr. Ingham’s approach.

  3. My intention in originating both the Carbon Farming Courses (CFC) and Carbon Economy Courses (CEC) was to develop a high end pedagogy that mimicked the successful formula of the Permaculture Design Certificate Course (PDC) and fill in the technical pieces that necessarily follow the foundational of the PDC experience. Certainly bridging the gap between related methodologies was also my intention and we have several folks who have already open their shops very well prepared indeed. It wont end here….

    All the best,

    Darren Doherty

  4. Allthough familiar with the name – and general idea – of Permaculture, but having never been on a course, reading the above gave me a good idea of what it was about. Lots of interesting things to get aware-of. The soil in my garden is in a generally sad state. dries-out quick to kind of concrete, sticks to your shoes as soon as there’s a drop of rain. Won’t grow Onions, cabbage or Cucumber. The only remedy I have, is, I guess, on the right track, to import tons of horse/sheep/Cow – whatever – manure but this takes time and energy and there are lots of other jobs to do. I would feel right about inviting a couple or more young WOOF-ers to become muck-spreaders for a week, particularly if there are any alternatives. Pigs in ? – too many fences required.
    So far all I have managed is to start a “compost patch” which is begining to make bit of potting-mix – after 2 or 3 years. Getting sustainable takes Time ! and that’s what modern life lacks. Everytrhing is too quick – and required yesterday !

  5. I’ve read tonnes of Ingham’s stuff, but I’m still unclear as to whether I want to encourage bacterial or fungal cultures in a particular tea. Pastures are bacteria dominant, so do I want to add to that, or balance it out with fungal brews?

  6. Balance it out with fungal brews, mate !. Every time ! – can’t go wrong ! Most of all don’t encourage bacteria, they just ain’t “Posh” !

  7. Hi Greg, it might be helpful in understanding Dr. Ingham’s work to know that there is an underlying ecological pattern of the relationship of soil microbiological population mixes to the above ground plant population mixes. For me a fundamental part of permaculture is identifying ecological patterns. Once you get the patterns, you can analyze and understand many ‘different’ locations, plant populations, etc.

    If you’ve ever been to an old growth conifer forest and looked at the forest floor you’ll see lots of fruiting fungi in the form of mushrooms. Dig into that old growth forest soil and you’ll see kilometers of mycelium strands (no wonder Paul Stamet who lives in the Pacific Northwest USA old growth forest country sees fungi as key to ecological restoration). In contrast, if you go to a drylands environment you’ll tend to not see fungi fruit (mushrooms) or visible mycelium strands in the soil. Or similarly, I think most of us would be surprised to see mushrooms growing in tilled agricultural farm fields. Why is this?

    Its because there is an underlying ecological microbiological pattern to all soils which is at its base the ratio of fungi to bacterial biomass in the soil. Over the past several decades soil microbiologists have been able to pin down a pattern of soil microbe and plant changes through time and space that they call “succession.” I think understanding microbial/plant succession is vital for any permaculturalist. Microbe/plant succession is a continuum. If you start on the extreme left of the continuum you get very “early” successional soils and plant communities where weeds (in the biological sense of weeds: annual, fast growing, tons of seeds, nitrate loving plants) thrive. A key to understanding why the weeds thrive is that the soil microbe population is bacterial DOMINATED. The fungi to bacteria biomass ratio is 8-10 more bacteria than fungi. The bacteria produce a sugar substance loosely called bacterial slime that is alkaline (slime is for protection, transport corridors, etc.) The slime drives the soil alkalinity here. So these bacterial dominated soils have a high ph. Without going into the details of microbial nutrient cycling, let me cut to the chase and say that the alkaline soil conditions results in a bunch of specific bacteria converting microbial cycled soluble Nitrogen into Nitrate. This process is called nitrification. And the bacteria that do it require high (alkaline) ph for the enzymes they use to convert Nitrogen into Nitrate to work. Weeds love high Nitrate levels. They’ll out compete “higher successional” plants any day if there’s tons of Nitrate in the soil.

    If you move to the right on the succession continuum you get a tighter fungi to bacteria ratio. In a soil where the fungi to bacteria biomass ratio is more balanced, lets say 1 to 1, you’ll find that “higher” level plants thrive and out compete the weeds. Higher level plants means in the context of the successional pattern and include annuals like tomato, cucumber, pepper,corn, etc. All these plants like to have their Nitrogen in two flavours: Nitrate and Ammonium. In soils that have a more balanced mix of bacteria to fungi the soil alkalinity is more neutral. This because fungi, as part of their ‘eating’ secrete acids as well as enzymes. The extra fungal biomass means extra acids being generated in the soil resulting in a soil ph change. As the ph moves closer to 7 (neutral) the nitrifying bacteria I mentioned above can’t as easily convert Nitrogen into Nitrate. Just a note, the soluble Nitrogen I originally mentioned above is actually Ammonium. So, if less Ammonium is being converted to Nitrate, the Ammonium to Nitrate balance is changing. Weeds like high pulse levels of Nitrate. When they don’t get it, they are on a diet and can’t thrive. In contrast the tomatoes and peppers do well with a bit of both Nitrate and Ammonium. Its important to understand, that the soil microbes are responsible for this. If we leave an area alone, the plants that grow will tell us the story of the fungi to bacteria ratio in the soil.

    If we move more to the right on the successional continuum we get ever increasing fungal biomass and ratio dominance. In a healthy vineyard soil you might see 3-5 times the fungal biomass compared to bacteria. A fruit orchard, 5-10 times fungi. A healthy old growth conifer forest 100-1000 times as much fungi to bacteria. Think about the plant systems we just moved into, they’re perennials. As we jumped from annuals to perennials we jumped into a fungal dominated soil. As the soil gets increasingly fungal dominated we get more and more fungi secreted acids entering the soil, resulting in an increasingly lower soil ph (acidity). When the soil ph drops below a nuetral 7 and becomes acidic, those nitrifying bacteria I mentioned above can’t convert Ammonium into Nitrate. The enzymes they use to do this just don’t function in acidic soils. So, the form of soluble Nitrogen in the soil becomes ever increasingly Ammonium. As we move into more advanced (in terms of succession) Perennials we get a greater love of Ammonium as the desired plant Nitrogen food. If you give any organism its preferred food it will out compete other organisms that have different preferred foods. Broccoli, for example, likes a more Nitrate rich soil with a fungi to bacteria ratio of .3-.7 approx (bacterial dominated). Chances are slim that you’ll find a ‘natural’ growing broccoli plant in an Ammonium rich old growth forest in California. Likewise, chances are slim that you’ll find a confer thriving in a tilled broccoli field. The soil fungi to bacteria ratios are different and give a competitive advantage to different above ground plants groups.

    When thinking about your field ask yourself some questions about the type of grasses you WANT to grow and the types of plants that seem to thrive there. Do you want to grow perennial grasses but lots of high seed yielding annual weeds thrive there? If so, you’ve got a bacterial dominated soil. Most of the time, we do need to move our soils along the successional continuum pattern and get more fungi in there, especially if the soils have been farmed (chemically or often organically). Farming practices of tilling, chemical ferts, pesticides and evening dumping manure on fields either kill fungi or overfeed bacteria. Both result in bacterial dominance.

    But here’s the rub. If I live in an old growth conifer forest in say Oregon, USA, and I want to grow a veggie garden I’ll most likely need to make my soil more bacterial. I mention this to point out that understanding the successional continuum pattern and what your specific soil microbe population is in relation to the plants you what to grow is always the first step. Getting fungi into many soils is often the first answer, but not always. Then once we’ve got the right fungi:bacteria ratio for the plants we want to grow, we need to look at the other members of the soil food web (ciliates, flagellates, amoebae, nematodes, micro/macro arthropods) and ensure their numbers and diversity are OK. But, first step, is the fungi-bacteria ratio.

  8. Many thanks for that one, Doug Weatherbee. I’ve learned more in 5 minutes than in the previous 40 ? years ?! – and I’ve only read it quickly because I should be in bed. Thank you !

  9. Thanks Doug,

    That article on successional continuum patterns is excellent. You have really nailed it, and I will read it again and again. If you have any other comments or suggested reading on this subject please feel free to share it.

    Kevin Gay

Leave a Reply

Your email address will not be published. Required fields are marked *

Related Articles

Back to top button