mycorrhizae tolerance to fertilizer

brateaver at brateaver at
Sun Dec 29 07:46:33 EST 1996

It is those who use any N form that is chemically produced who cause
nitrate runoff. There is a pile of literature that documents this. You
apparently are not familiar with the data that accumulate worldwide from
studies done all over the researched world sites.

Upper midwest soils, yes, they are deep, and that is mostly Iowa and
nearby, but that is due to some cause in the deep past, and it is
extremely unusual and local and is most certainly not an example to use in
favor of using chemicals.

Using grassed waterways, etc. is the way even the USDA recommends, but
these methods of conservation are not used widely in either the whole US
or the world. I used to read about such long ago, but it is not seen in
many current ag  journals.

And even if a farmer uses these Soil Conservation techniques, that will
never replace the need for continued supply of organic matter. Soil by
definition is a community of living entities.
   The remark that southern soils are poor, with one reason being given
that soil life is CAUSING the poor state is the most senseless remark I
have ever read, concerning soil.  It is just the OPPOSITE OF TRUTH.  The
only way real soil can ever continue to last is by means of just those
organisms.  How can any normal person say anything so silly?
   Using chemicals destroys them, and that is why most farmland in the US
today is eroding, dead and without the remedial efforts of soil organisms.

Provision of organic matter should be part of every farm routine in the
world, and it is done farmscale by rotation of crops with cover crops,
legumes and/or grasses. The Iowa monocultures of corn, corn, corn, are
kept going due to the natually and unusually deep soil, in spite of the
deleterious chemicals being supplied annually. Roots can go deeper and
deeper in desperation, while the chemical N runs off.

Everywhere else organic matter has to be supplied to the much shallower
substrate, to  make up for the harvested material removed. Cover cropping
is the easy and viable way to do this and successful organic farmers
expect to do this routinely. 

No-till adds only the residue of a harvested crop, not the enlivening
repertoire of a cover crop, or alternate growing of a legume crop. Residue
is not the same as an alternating soil-building crop.

Manure is always to be composted first,  before being spread, and
composting is part of an integral, properly run farm operation.

An alternative is a 7th year fallow, that will  naturally enable plant
cover to utilize manure. Weeds that grow without farmer effort will
utilize the nutrients in the manure over a year, and the lush growth will
repay what has been taken out the 6 previous years, when turned under.
   An advantage of such a fallow is the buildup of soil organisms, and the
fact that it takes 6 years for the original CO2 and water (making up the
plant cover) to return to CO2 and water again.

   Lush forests, where wild animals deposit manure on the land,  leaves
and twigs fall, and fallen dead trees gradually decay, do not cause
nitrate runoff. The system is a recycling one. A farmer,who needs to
annually remove a crop, needs to make the effort to do what happens
naturally in an undisturbed forest--replace the organic matter lost.

Mycorrhizae occur in all soil that has not been sterilized and are
particularly useful where the major nutrient  phosphorus is low, not other
major nutrients, so it is sloppy reasoning to call all such soils totally
degraded, just because mycorrhizae have been found useful in mine spoils,
for example.. They are part of the whole array of soil organisms that make
up real soil. 

Those persons who provide mycorrhizal cultures have found by experiment
that certain spp are particularly valuable for particular crops, and
enhance production for such.
Mycorrhizae are an excellent provision designed for soil that can take
advantage of their presence--that is why they are there naturally, ready
to get to work when needed.

P as a major nutrient is one of the many expenses of fertilizing soil, if
a farmer has to buy all the inputs for  the land, and mycorrhizae save
that expense. Making use of this natural provision is better than buying a
sack of superphosphate, which has a bad effect on zinc utilization in
   Mycorrhizae, INSTEAD, increase provision of whatever P is in low-P
soil, moving through an area of the mycorrhizosphere  much larger than
root hairs can forage, and gather up what they find to offer the crop,
including zinc as well as other micronutrients.

As for the cost, first deduct the cost of the P input that would not be
needed, and then remember that these valuable fungi reproduce themselves
by spores and increase steadily and even join with others in the area to
form a wide web of aid. They offer an addition of organic matter, which is
the most important input to soil. 
   Organic matter is the major factor in production of  real soil. Gary
Williams mentioned the soft, loamy soil that used to be normal but is
almost everywhere gone. The soil that is treated with chemicals is so dead
that growers using them have to keep using more and more all the time,
trying to artificially supply nutrients that the creation is set up to
normally supply it from organic matter.

   One final but extremely important point is that enzymes in soil are
derived from organic matter and soil organisms, not chemicals. Reactions
don't naturally occur without the aid of enzymes, so they are of the
greatest importance in real soil.
    Anyone who wants to see what chemicals do to destroy real soil need
only to go to a university experiment station and see what horrible, hard,
dead dirt university researchers CALL soil.

I once put on an exhibit at the big farm meeting annually held at
Asilomar, which I made by requesting from major university ag  soil
researchers a sample of the soil from the places where they did the
experiments they wrote about in journals. I got a small bag from each and
exhibited them, labelled. 
   It was quite a shock to those who took time to look at the exhibits,
especially when I showed, for contrast, some of the real soil I brought,
through which they could easily move their fists

   I will make one more point: To suggest that one cut down a forest,
which is growing on soil naturally supplied with organic matter, to supply
organic matter that routine cover cropping should offer to farm land,
                                     IS PLAIN ASININE.   .

B. Rateaver

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