Healthy soil and sustainable growing

["Tradingpost" <tradingpost@lobo.net>]

Apparently soil tests were originally devised to check soluble nutrient 
levels for adding additional synthetic fertilizers. They began in days of 
yore, when Liebig's chemistry approach dictated that only soluble salts were 
available to plant roots, before the real complexity of soil biological 
activity was beginning to dawn on soil scientists.

See
http://www.ibiblio.org/london/permaculture/permaculture-list-archives-1999-2002/msg03631.html

Also from
http://www.soilandhealth.org/01aglibrary/010112krasil/010112krasil.ptIII.html
     In counterbalance to the theory of Liebig, he (Pryanishnikov) ascribed a 
major importance to the biological processes of the soil and especially of 
nitrogen accumulation...  the theory of Liebig is still reflected in the 
studies of many specialists. In the theory of plant nutrition one observes an 
obvious underestimation of the role of the organic substances of the soil, 
and its importance of the nutrition of plants is often denied altogether. .. 
Many plants assimilate organic substances, metabolic products of microbes 
which live on and inside the roots. The best known plants are those in the 
tissues of which there are bacterial microbe-symbionts, actinomycetes, and 
fungi... The best known symbiosis is that of plants with mycorhiza fungi. 
According to the data in the literature, there are mycorhiza fungi on the 
roots of almost all plants which are to a greater or lesser degree symbionts. 
The symbiosis is such, that some plant species cannot grow without the fungi.

And
http://www.hort.purdue.edu/newcrop/history/lecture31/r_31-2.html
     According to Balfour (1947), Liebig's theory of mineral plant foods was 
a "rather naive theory" since it considered only mineral salts. As noted 
earlier, a concept of a dynamic, living soil was beyond the scope of Liebig 
or any of his contemporaries. It is, perhaps, more unfortunate that, even 
today, this view is still held by many.
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 I'm not against all soil tests in all cases, just the overreliance on 
results. The tests run by most extension offices generally will just 
recommend some kind of synthetic N-P-K, as fertilizer companies don't include 
much of the dozens of other elements needed for plant growth (or organic 
matter for microbe populations & soil texture). Soil tests sell a lot of 
commercial fertilizer. And resulting weak plant growth sells a lot of 
pesticides. Many well meaning writers urge soil tests, but it's not enough 
and can be misleading.
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paul tradingpost@lobo.net