Re: [compost_tea] soil chemistry facts

From: <soilfoodweb_at_aol.com>
Date: Mon, 30 Aug 2004 10:37:19 EDT

Let's go back to what I said in my e-mail.

Working with Graham Lancaster at Southern Cross University, we have the data
showing that no nutrient element is limiting in any soil. the total
extractable nutrients - N, P, S, Fe, Ca, Co, whatever - were not in any way even close
to the limiting level in any ag soil in Australia.

Ok, Do we all have that fact clear? Don't add any other interpretation to
that piece of information. No other extrapolation. This is fact. I will get
the data to show you and post it to the e-zine. Graham and I will work on a
paper to be published in a scientific journal.

OK.

Then, the next step is, what makes nutrients available? That means, what
solubilizes nutrients? And what we mean by that is, what moves a nutrient from
the total extractable pool, which may not be available to plants, into the
exchangeable pool, which are nutrients in the soil solution, which are nutrients
available to plants?

The only way to do that is through the action of organisms. Many papers have
been written about hte phosphate-solubilizing bacteria. I don't really have
to put up a list of those references, do I? There are thousands of papers
about nitrifying bacteria. there are hundreds of papers about nutrient cycling
occurring through the actions of protozoa, nematodes and microarthropods. The
Soil Biology Primer, the Ecological Monograph by Ingham et al in 1986, any of
David Coleman's books, papers by Paul Hendrix, Darvid Wardles' book, all cover
this topic quite well.

There are papers about how microorganisms move any mineral from the
not-soluble pool to the soluble pool of nutrients. It is in the scientific
litereature. Maybe Steve Diver has reviewed it on the ATTRA website.

Now, you bring up the fact that addition of inorganic nutroents can improve
plant growth.

I am NOT disputing that. This isn't an attack on the fact that when
AVAILABLE nutrients are not present, that addition of available nutrients helps plants
grow.

But the real question is, why aren't the nutrients that are in your soil
available? why are they stuck in a plant un-available form?

Answer: the biology has been killed, or wasn't there to begin with.

How did the biology get killed? Inorganic fertilizers and pesticies.

How to get the biology back? Compost, compost tea.

How much compost tea? We need to do studies to figure this out. Neither you
nor I can make recommendations without data. How much biology is required,
and what are the foods needed, to keep the organisms active?

the data are not present for each nutrient element. We have some clues for
Ca, and for N.

compost tea added at 100L/HA as soil drenches, 25L/Ha for foliar
applications. You may need "kick-starts" of Ca, and fungal or bacterial foods to get
things going. Testing your soil to determine whether the kick-start has happened
is necessary.

Elaine R. Ingham
Soil Foodweb Inc., Corvallis, Oregon
Soil Foodweb Inc., Port Jefferson, New York
Soil Foodweb Institute, Lismore Australia
Soil Foodweb Institue Cambridge, New Zealand
Soil Foodweb Inc., Hilversum, The Netherlands
Laboratorios de Soil Foodweb, Culiacan, Mexico
Soil Foodweb Inc., Jerome, Idaho




Received on Mon Aug 30 2004 - 11:29:38 EDT

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