JEFF LOWENFELS | The Organic Gardener's Guide to the Wonderful World of Soil Microbes | Bacteria, Fungi, “Rhizophagy” & the Root Zone
Here's what you've been missing. If we work with the Soil Food Web, we get better results with less effort.
My guest is Jeff Lowenfels, author of the four books series:
Teaming with Microbes,
Teaming with Bacteria,
Teaming with Fungi and
Teaming with Nutrients,
which is all about the soil food web, the living world beneath our feet, which could make all the difference in our gardening and our farming, our food production and our health, not to mention our water quality.
HART HAGAN: Jeff, how are you today?
JEFF LOWENFELS: I'm great. Couldn't be better and great to be here.
HART HAGAN: So you're in Alaska, right? What's it like in Alaska today?
JEFF LOWENFELS: Well, today we have a rare sunny day and it's going to be above freezing, which in the winter is a little bit rare. So we're kind of excited about it.
HART HAGAN: Jeff, what motivated you to write this series of books?
JEFF LOWENFELS: What motivated me to write the series of books? When I discovered what the real food web was about, it was because of teachings from Dr. Elaine Ingham. She's the guru of the soil food web. When I learned about the soil food web, I asked her why everybody in the world, particularly gardeners, don't understand the soil food web.
She said that it’s just too hard to get traction. So I said, “I can write your book.” So I wrote a book. And I've been pushing the soil food web ever since. It really is a beautiful system that people will adopt if they haven't already.
HART HAGAN: Jeff, what have been some of the big developments in soil science in recent years.
JEFF LOWENFELS: Well, I think you have to start with the soil food web itself. Before the year 2000 or so nobody talked about bacteria and fungi and things in the soil food web. I should give a quick definition of the soil food web. Everybody knows there are soil food chains where the little guy gets eaten by the bigger guy, which gets eaten by the bigger guy. There are lots of those chains in the soil and every now and then something on one of the chains looks up, sees something in another chain and says, I can eat that, and does so, and connects the two chains. And eventually you end up with a web of who eats whom in the soil.
The reason why this is important is because the way plants operate in nature is they use almost half--maybe even a little more--of their photosynthetic energy to produce things that are called exudates, which drip out of the root system and attract bacteria and fungi. The bacteria and fungi take the carbon out of these exudates, and they in turn attract protozoa.
Then nematodes eat the bacteria and fungi, and poop out the excess that they don't need. That turns out to have an electrical charge on it, and also plant nutrients in plant usable form.
That's how plants get their nutrients in nature. We need to be doing that same thing, or at least not disrupting that process, as we garden. And as we grow food in agriculture.
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HART HAGAN: Jeff, when gardeners and farmers don't understand the soil food web, what are they missing?
JEFF LOWENFELS: Well, I'll give you a perfect example. One of the greatest new things that's been discovered about the soil food web is a process known as rhizophagy, whereby plants summon those bacteria with root exudates. The bacteria are attracted by the root exudates and then pulled inside the root system. These bacteria are not eaten, but instead go inside the newest plant root cells. And once they're inside they produce nitrogen inside the plant. They fix nitrogen inside the root.
If you're not cognizant of the soil food web, you don't understand that up to 40% of your nitrogen could be coming from these bacteria, and you're probably not treating the soil in a way that respects them so that they can give you that free nitrogen.
So there are lots of new things that are being discovered and when you layer them on top of the Dr. Elaine Ingham soil food web process, you begin to discover that we should change the way we grow things or we're not going to be able to take advantage and team with these microbes that feed the plant.
HART HAGAN: So what do people normally do that is harmful to the soil structure and the soil food web?
JEFF LOWENFELS: Well, the first thing they do is they use chemical fertilizers, which are really destructive to the soil food web for a couple of reasons, not necessarily that they kill the microbes--although some of them do, because the chemical fertilizers are salts and they blow them apart--but they change the population of microbes that's naturally there.
They cause the plant to say, “Gee, I'm getting free nitrogen. Why do I need to produce so many exudates to attract these microbes?”
Once you don't have the action of the microbes, and once you lose those microbes, you end up losing soil structure, because those microbes glue together soil, weave together the soil, make burrows in the soil that act as reservoirs for organic material, water and air. Once you start using chemicals, all this goes away.
We rototill. Rototilling disturbs that great fungal network that feeds the plants. It puts the bacteria that are supposed to be in the root zone in a different location and when you cut a worm in half, you don't get two worms unless you cut it right at the 18th segment . So yeah you get two halves of a dead worm, you know.
TAKEAWAYS:
Tillage is harmful.
Chemical fertilizers are harmful.
The soil food web is a living ecosystem that nurtures our plants and saves us work, if we will let it.
Please click on the link and watch the full interview.