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From: Oz <>
Newsgroups: sci.agriculture,sci.agriculture.sustainable,misc.rural,rec.gardens
Subject: Re: High Plains Journal editorial on Organic Farming
Date: Fri, 6 Feb 1998 23:53:38 +0000

In article <01bd3342$6dd0cae0$840be7cd@jeanie>, Don Chapman <don@bio-> writes
>Oz <> wrote in article
>> In article <01bd3327$54c3c860$3b0be7cd@jeanie>, Don Chapman <don@bio-
>>> writes
>> >However, I believe that the majority of modern soil scientists would
>> >agree that even bare-bones organic methods are more sustainable than
>> >the equally simple-minded application of NPK year after year.
>> Yes. However who ever said that this was what is done 'conventionally',
>> particularly when it isn't.
>Then just what is really in all those truckloads of bags labeled with NPK
>analysis numbers that are shanked into the soil next to seeds during
>planting?  Would you mind explaining what conventional ag farmers do use as
>fertilizer?  Would you please elaborate on your "particularly when it

It isn't *ONLY* NPK that conventional farmers use. As required by soil
analysis they may apply Mg, S, Cu, Zn and a whole host of other
nutrients and trace elements depending on what (if any) is deficient in
their soiltype.

>> >At some point, if the
>> >humus
>> Non-'organic' farmers spread manure too. Because of the higher yields
>> from 'non-organic' crops the total return of organic matter from roots
>> and crop residues to the soil is probably higher in a 'non-organic'
>> system than in an organic one.
>That's a new one.  I've never seen any research on that.  Have you?

You don't need much research, just a calculator. It is generally agreed
that the plant biomass above ground is about the same as the biomass
below ground. Now take as an example a good wheat crop of 9T/Ha. Given a
harvest index of 50% you get about 9T/Ha of straw and 18T/Ha of roots.
Total 27T/Ha. Now, just to be nice I'll round that down to 20T/Ha. Doing
the same thing for a 4T/Ha organic crop gives you 4/9 of 20 or 9T/Ha.
The difference is 11T/Ha which is about 10T/Ha of DM. Typical manure is
about 15% DM so 10T DM is found in 67T Manure. So to equalise the
organic matter, and thus humus between the two you must apply EVERY year
about 67T manure/Ha or 27T/Ac on EVERY field (I doubt any organic
farmers manage that). Of course manure breaks down more readily and so
persists less long in the soil, and non-organic farmers also apply
manure. The conclusion is clear.

>> >and trace elements are not replenished, soil will develop problems.
>> For 'non-organic' farmers the application of trace elemets is of course
>> trivially easy. They buy exactly what is required and apply it, thus
>> fixing the problem.
>How do they know "exactly" what is required?  Are you aware of any that
>measure more than maybe zinc and magnesium, in addition to the NPK

My standard analysis, done every three years, measures:

P, K, Mg, Na, Mn, Zn, B, S, Co, Cu, Mo, Fe, Ca, pH, humus absorbion.

>Are the dozens of minor and trace elements totally unimportant?

No. Few are limiting though.

>Are you sure?  (As a parallel, would you say that iodine is unimportant to
>humans, even though we only need it in tiny amounts?  Hear much about
>goiters these days?)

The mammalian requirements (eg Se, I, Co etc etc) are covered by the
trace element inclusion in my cattle diet (which is at high levels) and
spread to the rest of the farm in manure and slurry. In this way
deficiencies in imported foodstuffs are overcome.

>I'm not quite convinced that chemical farmers are
>indeed "fixing the problem", or even that they are measuring more than the
>most obvious problems.

The yields will tell in the end.

>Of course this is not possible for 'organic' farmers
>> so, despite their claims to the contrary, it's not clear to me how the
>> correct their trace element problems, if they can.
>Usually, this is done by applying various broad-spectrum minerals in
>powdered form.  Such things as humates, azomite, greensand, montmorillonite
>clays, mined volcanically-changed Dacite, etc.  The general theory is not
>to necessarily measure what is lacking, but rather to provide every
>possible needed element to the soil microbial populations to convert to
>forms that plants can use, and let the plant-nourishing mycorrhizal fungi
>give plants what they need.

No joy if you have (as I had) Cu levels of 0.1ppm.

>> How would an 'organic' farmer fix a manganese deficiency problem on a
>> calcaerous soil, for example? I don't see how they can.
>I'm sure you are aware that there are a wide variety of naturally-mined
>minerals that are permitted to be used for certified-organic production.
>We, for example, carry a volcanic mineral with 120 ppm manganese and a .005
>concentration of manganese oxide, along with over 40 other identified
>elements.  These tiny amounts are sufficient for plant needs, as they
>operate as catalysts in plant growth, rather than as cell-building
>materials per se.

I have a natural level of Mn in my soil of around 300ppm. In the organic
areas the crops will literally die at a few leaves from Manganese
deficiency no matter how much I put in the soil. For the plants to get
it, it HAS to be sprayed as a soluble salt. I doubt your 'volcanic
minerals' contain significant soluble Mn.

What is 'naturally mined'. How can anything be 'un-naturally mined'.

>Organic growers are not restricted to animal manures,
>and with proper strategy, can probaby grow crops on poorer soils than
>conventional farmers.

Such as, I suppose, rock phosphate (produced in the very same mines that
produce, after simple processing) my triplesuperphosphate. The only
difference is the use of naturally oxidised and mined sulphur that
concentrates the phosphorus so as to reduce transport costs and thus
unnecessary waste of fossil fuel which would contribute to global

>> If all the farmers in the catchment area of the Mississippi went
>> 'organic' and so used some gigatons of human and animal manure then I
>> wonder what the nutrient status of the Mississippi would be like? Not
>> very good, I suspect. I would not like to imagine the effect of a mid-
>> spring flood on the ocean ecosystem.
>You seem hung up on organic=manures.  Manures are not all that great a
>fertilizer.  They have been used by farmers for ages mostly because farms
>used to have huge amounts available free, back when a farm meant having
>both cows and crops.  As part of a soil-improvement program, well-composted
>manures can be very helpful, but modern soil scientists certainly do not
>suggest relying on it alone.  Way back at the beginning of my post, I said
>there seems to be a problem in defining "organic".  May I suggest we would
>have a better discussion if we used:  Chemical-based growing versus
>Biology-based growing?  I think that the very word "organic" is a problem

So what is your source of P & K that is so wonderful?

>> So converting to 'organic' isn't a cure to these problems at least and
>> would probably make it very much worse.
>Sorry to disagree, but I disagree if you are saying that the best possible
>way to grow food crops is with the chemical methods that have been in use
>since the end of WW2.  What seemed to be a wonderful and convenient "Green
>revolution" in ag is showing some serious side-effects.  Look for NPK
>fertilizers to be severely restricted sometime in the next few years, and
>water contamination will be the triggering issue.

Biggest phosphate polluter in the UK (by far) human sewage plants.
Potassium is not, so far as I am aware, implicated in anything. Nitrate
contamination is far more easily controlled by using bag fertilsiser.

>Also, look for more use
>of living soil organisms that can replace large amounts of fertilizer to
>gain much wider use.

Personally, if the soil ain't got it and the plants are deficient, bugs
can't help any.

>I might guess that some combination of
>synthetic/organic/biological methods will replace the flawed "all
>chemistry" concept.

As a farmer I use all possible means of improving my crops. Certainly a
high levels of bacterial activity in the soil is very helpful and I do
all I can to preserve soil structure and it's biological activity. I
also use knowledge of pest/pesticide and environment population dynamics
to minimise pesticides and maximise plant protection. So do all farmers
I know, to greater or lesser extent. What's new about this?


From: Oz <>
Newsgroups: sci.agriculture,sci.agriculture.sustainable,misc.rural,rec.gardens
Subject: Re: High Plains Journal editorial on Organic Farming
Date: Mon, 9 Feb 1998 06:58:55 +0000

In article <>, Dan Sterner
<> writes

>As far as the conditions when you moved onto your land, who knows?
>Without knowing what the owners before you actually did it's hard to say
>what the problem they had would have been.

Well, there were people who had worked on this farm since the early
1900's still in the village. There are still people in the village who
worked on it in the 30's. They have good memories. Taking it further
back is relatively straightforward as there are several histories
written by the two antagonistic local families (one Baptist and one
Church of England) that takes it back another couple of centuries.

>Many things (such as tobacco
>products) that some people considered good organics are becoming less
>and less common as the years go by. Simply not making use of a lot of
>chems isn't enough if they didn't add a lot of organic matter and so on
>in an intelligent manner. That's part of the problem with discussion of
>organics, it means different things to different people so the debate
>ends up getting confused all too often.

They used all the organics they had. Horse, sheep, pigs and cattle. Not
enough. Mind you to be fair the iron age people were responsible for
much of the soil depletion.

>BTW, pesticide use doesn't seem to be a great problem to earthworms,
>they can take quite a bit of the mild ones from what I've read on them.
>What seems to bother them more is sudden changes in ph, salt content,
>etc. so fertilizers are more of a concern with them. Other soil life is
>another matter.

Natural soil levels here ar pH 7.7 to 8.2. Salt levels are not a problem
in the UK, too much rain. When we came here PK indexes were pretty much
zero all over and crop yields truly dreadful. Over two decades we have
jacked up the PK levels to 2 to 4 , yields have increased hugely and as
a result the amount of organic matter returned to the soil has increased
dramatically. It's this increase, together with better nitrogen levels
that has increased the biological activity of the soil and thus the food
for the worms and hence the plague of moles. Interestingly on the
naturally high organic matter areas (up to 40% OM) we didn't have moles
before either, but now we have. I suspect that the peat was rather dead
and sterile and so provided a poor foodsource for the worms, but not
now. One should also bear in mind that the pesticide absorbtion and
degrading ability of soils is strongly related to the activity of the
topsoil so that although we do use pesticides extensively, the effect
may be mitigated or removed. We do have a problem with efficacity of
some soil applied pesticides.


From: Oz <>
Newsgroups: sci.agriculture,
Subject: Re: Pesticide Problems
Date: Sun, 22 Feb 1998 09:17:52 +0000

In article <vlLH.38$>, Brad Thorarinson
<> writes

>The low-input, "organic" agriculture of the Great Plains in the U.S. in the
>last century and the first half of this one was the mining of the natural
>fertility of those soils.  A lot of those settlers had been farmers in the
>eastern seaboard, who moved west when ~those~ farms became depleted of
>nutrients and unproductive. A gross simplification, but true.

It's very similar to what is happening in the rain forests today, if you
think about it. Given that much of the produce fed the UK, returning the
sewage would have been an interesting technique. :-)

>I'm not too familiar with the situation in Europe, Asia, or Africa prior to
>modern industrial agriculture, but I believe generally soil depletion was the
>norm in all of these as well,

Not 'arf. One of the reasons for the success of the viking expansion in
the UK was the utilisation if previously unfarmed parts of e.anglia.
These were called the breklands (from break lands = ploughable land).
The soil was light and sandy and rapidly (perhaps after a few
generations) became a sandy wasteland sparsely covered by weak trees.
With modern fertiliser and irrigation it's now prime carrot and potato
land. The same thing happened several thousand years earlier on the
chalk downlands in late stone age times. The easily ploughed chalkland
was ideal for cereals, the springline below ideal for villages which
were adjacent to damp river valleys for summer grazing. Since it was
impractical to take muck uphill to the cereal fields the downland became
utterly depleted and was only fit as poor sheep grazing (much was
unfarmed) until the second WW.

>except for areas such as the Nile delta which
>were replenished by nutrients from elsewhere.  And this was at production
>levels generally much lower than in modern times.



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