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Re: British Beef Situation



In article <4luiv3$ba6@news1.exit109.com>, "Nathan D. Justus"
<nathan@exit109.com> writes
>In article <f6DgDBAarzfxEwU$@upthorpe.demon.co.uk>,
>   Oz <Oz@upthorpe.demon.co.uk> wrote:
>
>>With enough manure and no attacks of pests and diseases location then 
>>vegetable crops can be grown with little difference between organic and 
>>conventional. However it's as well to note some differences. One problem 
>>is the mismatch of nutrients in organic manures. So growing potatoes on 
>>a clay that liberates potassium is fine as you really only have to apply 
>>enough manure to provide the nitrogen for the crop. Admittedly the high 
>>nitrogen early in the season results in a lot of small potatoes rather 
>>than a few big ones and so large peeling losses, but still. Try to grow 
>>them on a non-potash liberating loam and you are in all sorts of 
>>trouble. The correct amount of potash results in a massive overdose of 
>>nitrogen.
>
>Yes, I agree.  And I never did say that we shouldn't rely on proper analysis 
>of the fertilizer being used.  

Bear in mind that manure comes with whatever nutrients it has. It is a 
highly variable product with uncontrollable RATIOS. As a result it is 
virtually impossible to use it completely efficiently on it's own. 
Rotations can help here, but the problem is essentially that manure 
wasn't designed to maximise crop production and minimise nutrient
wastage.

>What I did say - or thought I said, though I 
>may not have stressed it - is that if we don't build the soil, but rather 
>simply allow it to keep turning into dust-like textures, we're killing the 
>croplands. 

I doubt you will find any farmer who disagrees with you here, or any who 
does not have this in mind. After all the soil is his livelihood, of 
course he does his best to look after it.

>>Of course if you get blight then the crop is a write-off.
>>If you get aphids you are in trouble.
>>If you get Colorado beetle you are in serious trouble.
>>etc. etc.
>
>This is true.  However, biological controls for insects also exist.  

I don't know of any on a field scale though they do exist on the
continental scale. Screwfly in the US, and an insect pest of pricklly
pear in Australia come to mind. They are, I believe, common in
greenhouse agriculture.

>And even 
>if we used chemicals - there are chemicals that are less destructive to the 
>environment.  It's all about _choices_ for what we use.

I don't know about the US, but chemicals that are destructive to the 
environment are not permitted in UK. In this area we must be careful to 
distinguish between chemical usage in the 50's and 60's when much less 
was known about accumulation and toxicity outside the target, and
several mistakes were made. It is, for example, vastly harder and hugely
more expensive to register an agrochemical these days than a
pharmaceutical product because of all the testing that is required.

>personally, I see no reason to go back to the dark ages - we've learned a lot 
>in the last few centuries, why throw it away?  I only believe that we need to 
>consider our actions in light of long term effects of them - who would have 
>thought, forty years ago, for example, that disposal of radioactive waste from 
>nuclear power stations would become such a big problem?  Or the decomissioning 
>of the stations themselves?

Nimby?

The long term effects of chemicals is already tested for. Since the
agrochemical companies pay there is no restriction on how many tests are
asked for. Of course the whole population pays in the end, but it's more
spread out.

>Of course, we're not set up for real stable state recycling - where _all_ our 
>organic wastes go back to the land.  That would take massive, massive 
>enginering efforts and wholesale changes to society.

Actually in the UK away from ports disposal by application to land is 
normal (after treatment)from non-industrial sources. Since the sewage 
companies charge very heavily for contaminated wastes, the contamination 
of sewage by toxic compounds has markedly reduced. Since dumping at sea 
is no longer permitted the UK must be heading towards a high proportion 
of sewage sludge to be utilised on land. I would be surprised if the US 
wasn't similar, if rather less obvious.

>And I certainly must defer to your firsthand experience of dealing with the 
>land - however, if your farm was farmed semi-organically, you used bag 
>fertilizer as a supplement, and still worked to keep the soil healthy, this is 
>the type of land care that I am thinking of - the thing that I was thinking 
>was so bad is something that happens here - where there are so many chemicals 
>dumped on the soil all the insects die, and the land becomes essentially dead 
>dust.

Er, no. You have got it backwards. Our predecessors farmed semi-
organically and the result was nutrient-poor soil with very low soil 
organic matter, low yields and few earthworms. We are most definitely 
NOT organic. 

There are quite a lot of things that people forget who are not involved 
with agriculture. My examples apply to the UK.

Firstly unless nothing is exported from the farm, nutrient levels will 
fall because of the nutrients that inevitably leave the farm in the 
produce. There is nothing you can do about that unless you become 
entirely self-sufficient, sell no produce and recycle your sewage. Even 
then you will lose some nutrients like sulphur and potash. Sulphur you 
can get from the air if it's adequately polluted with SO2, but others, 
like potash are a problem. There are a number of nutrients like this. So 
unless you import nutrients the fertility of your soil MUST slowly 
decrease.

Secondly organic matter recycled through the soil is dependant on yield. 
So a long term organic cereal crop is likely to yield (UK) about 1.5T/ac 
give or take half a tonne. Round figures indicate (including roots) that 
1/4 to 1/3 of the organic matter produced by the plant ends up as crop. 
The rest is straw and roots. So this crop will have produced about 4T/ac 
of residues that are returned to the soil to maintain soil organic 
matter levels. Note that manure (solid) is about 85% water, so this is 
equivalent to about 25T of manure/ac, which is a huge amount way, way, 
in excess of what would be *applied* when spreading muck. Now consider a 
high yielding modern crop of about 3.5T/ac, no lets take a moderate one 
of 3T/ac. This delivers double the organic matter to the soil equivalent 
to 50T of manure/ac. Now it's not hard to see why high yielding crops 
result in higher soil organic matter and thus higher yields in soils of 
higher organic matter (and nutrients for that matter). This stabilises
at a higher level of organic matter in the soil for the non-organic
intensive cropping system.

So the entire subject deserves greater thought than you might expect at 
first glance.

Enough for now.

------------------------------- 
'Oz     "When I knew little, all was certain. The more I learnt,
        the less sure I was. Is this the uncertainty principle?"




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