permaculture

["Lawrence F. London, Jr." <lflj@bellsouth.net>]

------- Original Message --------
Subject: Re: [SANET-MG] Achieving High Nutrient Levels in Crops (was 
History of Organic Agriculture slide presentation)
Date: Sun, 28 Oct 2012 13:40:19 -0400
From: Michael Astera <michael.astera@GMAIL.COM>
To: SANET-MG@LISTS.IFAS.UFL.EDU

Heide-

Thanks for slogging through the tissue testing paragraphs.  I mostly
posted those for the record, my argument for using them. We do need
some standards of nutrition in crops.

High Brix is another trait that modern crops have not been bred for.

My experience with Brix testing tells me that it's very good for
relative comparison, like two varieties side by side in the same soil,
or two tomato fields in central California, but not valid as a
benchmark by which to compare absolute quality.

It is much more difficult to achieve high Brix in a short season
temperate climate than in a tropical or subtropical climate.

That said, if two varieties of the same crop are grown side by side in
the same soil, the one that is higher Brix will tend to have higher
levels of nutrients overall, and the same with a single variety grown
in different soils: The produce with the higher Brix will tend to have
higher overall mineral nutrient levels. A notable exception would be
sweet corn varieties bred to produce very high sugar levels.  They
will have high amounts of sugar and not much else.  The corn kernels
may read 25*Brix, while the sap of the plant is only 2 or 3* Brix.

As another example of the potential confusion about Brix, a colleague
in Arkansas recently reported on harvesting acorn squash.  After
putting the squash in storage he noticed some sap coming from the
stems and got a Brix reading of 25*, very high.  When he cut open a
squash and measured the brix of the fruit itself, it was only 5*Brix.

I do think the bottom line is that our crops simply have not been bred
to uptake minerals or for any other nutritional qualities.

Michael A
http://soilminerals.com

On Fri, Oct 26, 2012 at 11:14 PM, Heide Hermary
<heide.hermary@gaiacollege.ca> wrote:
Thank you for that reference, Michael.  Much easier in this format than 
the old spreadsheet they used to have.
Interesting that you use tissue testing
I tried using Brix values because it is so simple, but I cannot get very 
high numbers in spite of a high OM content.
Yet everything tastes incredibly sweet and rich, keeps well in storage 
and we see next to no health problems on 30+ varieties of food plants.
I had hoped that Brix values would be a useful indicator of nutrient 
content in general, but something doesn't quite correlate in my eyes,
unless I truly am still not able to grow really high quality food.