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Old 09-06-2004, 03:18 PM
Chuck
 
Posts: n/a
Default Organic does not mean pesticide free...

Actually, the plots appear to be selected after the idea was formulated.
Good research makes a supposition and then does the experiment to prove it
factual, not the other way around.

Chuck


"Gordon Couger" wrote in message
news:6W7xc.9290$1L4.1531@okepread02...

"Oz" wrote in message
...
Gordon Couger writes

Before swallowing the yield claims of organic corn being 94% of
conventional corn I would like to see the trials.



===========posted a couple of years ago=========

With considerable difficulty I have obtained permission to post part of
the 2001 ARC results.

Cirencester Organic after grass ley.

Top: 5.54 T/Ha. (deben)
Ave: 4.61 T/Ha

Of interest
Widgeon @ 3.96 T/H
Squarehead Masters : 2.61 T/Ha (worst)

Squarehead Masters is a 19C variety. A major variety grown for decades,
possibly a century. It went flat, but straw to be sold for thatching. I
have seen this variety grown in plots (supported by canes) and it was
over 5' (1.5m) tall. It's a classic low fertility weed outcompeting
variety probably similar to landrace varieties grown for centuries.

The conventionally grown trial at Cirencester (but obviously not the
same field) yielded 8.3 T/Ha ave with the best variety yielding 9.9
T/Ha.

Comments would be as previous trial post.

NB UK arable farmers really should join ARC and get this, and a truly
vast array of other data on timings, seedrates, pesticide trials etc
etc, complete. (www.arable.co.uk)
========================================
=====Posted by torsten snipped
Below, some results from the Elm Farm Research Centre
stockless organic trial, Berkshire.

Rotation Course 1 2 3 4
A Red Clover Winter Wheat Winter Wheat Spring Oats
B Red Clover Potatoes Winter Wheat Winter Oats
C Red Clover Winter Wheat Winter Beans Winter Wheat

All first wheats which followed the fertility build achieved similar
yields
(A2 and C2), wheat following wheat (A2 to A3) yielded much lower
than wheat following potatoes (B2 to B3)

Wheat yield (t/ha at 15% moisture) means, 1988-1995

Winter Wheat
A2 A3 B3 C2 C4
Yield 4.21 2.67 4.34 3.77 4.05

[Oz: notice appalling yields]

The yield achieved by C4 indicates the grain legumes, which when
harvested do export much of the N they have fixed, still can leave
sufficient reserves to advantage the next cereal crop.
=====================
=====another ozpost
Source: Crops magazine (Reed business pub) 6 Nov 1999 P10

This article discusses a 'unique' ten year experiment comparing large-
scale organic, integrated crop management and conventional side by side.

I can't type out the whole article but the following points are made.
[NB View tables in a monopitched font]


Yield wheat T/Ha

Year 90 91 92 93 94 95 96 97 98 99
Con 8.7 7 7.8 9 7 7.25 9.25
Org 5.2 5.2 5 5.8 4.9 4.5 4.85
ICM 7.8 7.9 8.3 8.3


ROTATIONS etc

Organic:
Organic approved pesticides and fertiliser.
Two year clover-grass conversion ley. Then
a) Spring wheat/winter oats/winter beans/winter or spring wheat
b) 18mth red clover
c) spring wheat.
[This isn't very clear but I *think* they mean combinable crop (winter
or spring), 18mth red clover followed by spring wheat and then
cycling:Oz]
==================

There are more, but that will do.

Do the conventional plots rotate the same as organic plots, are they in
continues wheat or some other rotation. The largest loss in organic
agriculture is the years that the land is in low production rotations that
produce low value or no value crops.

Gordon