Subject: More Soil Quality and Def.

From: Charles Benbrook <[email-masked]>
Date: Mon, 27 Feb 1995 09:30:07 -0800 (PST)

The long post on Ikerd's sus ag discussion paper is interesting and
raises all the right questions/admonitions etc.  But as I have said
before I think the community has reached about as explicit, useful,
concrete definition of sus ag as now possible, or possible at any given
time, given the differences of opinion, world view etc that exist.  At
any point in time, in any society, the definition of any concept like sus
ag is going to be a compromise among differing world views, sets of
values etc, no one of which has any way to prove the other wrong, or
illegimate.  So the sus ag tent is now relatively stable; its shape and
inards perhaps fully pleasing to no one, but I am certain there is no
real point in debating the fine points anymore because we will simply
document more crisply the differences that are out there, and have been
all along.

        One of the other realities is that the "definition" of something
like sus ag is going to remain fluid, driven by changes in politics,
idealogy, science, community values, etc.  If we re-open definition of sus
ag in 1995 farm bill, I guarentee the result will be displeasing to those
who advocate a social justice leaning definition.  But while the political
arena has moved underneath the definition, the scientific community seems
to be moving in other, positive directions.  Abelson's recent editiorial
in Science on sus ag, with  at least some mention of soil quality, along
with its discussion of trends, etc is better than what I would have
expected given his views about pesticides, risk assessment, and the need
for environmental protections.

        So, I hope people will stay focused on things that are amendable
to meaningful change, like studying the economic tradeoffs of farm bill
proposals that will shift the relative profitability of different systems
and technologies.  People worried about corporate hog farms should focus
on IFPs and manure management because that is where that industry is
vulnerable.  I also think there is a firm enough concensus now on the
essential dimensions of soil quality to craft some useful provisions
focusing on identifying soils that are seriously impaiired for reasons
other than erosion, and providing farmers technical and financial
assistance for starting along the path to enhance their quality.

        On the issue of N leaching and fertilizers versus organic matter,
it all boils down to the ability of a soil to store and cycle nutrients.
Recall the excellent work of those who developed and have adapted to
various regions the side dress N test kit; there needs to be 21 ppm, if
memory serves me correctly, of N in the root zone to support maximum
growth of a corn plant.  The fertilizer guys are right that they can
control/predict levels, but are dangerously misguided in thinking that it
is better to meet N needs with fertilizer on dead soil than with largely
organic matter sources/cycling in an alive soil.  There is lots of
research basically proving this, but the fertilizer guys know how to look
creatively at numbers, and will put forth studies/data that show that N
loss can be great from orgo systems.  Of course they can.  Do not
underestimate mankind's ability to mismanage an agroecosystem, regardless
of its genetic heritage.  But in general a trashed, low soil organic matter,
compacted soil, like so many in America today, will lose more N per average
bushel of corn yield than a healthier, well managed soil.  Period.  If
you set two soils up in a fair comparative trial and use the same degree
of "best available technology" for meeting N needs and controlling N
losses, the higher organic matter soil will support same yields with
manybe 20-30% less N, and loose less than 1/2 to the environment, if the
research I have been reading over the last few years is to be believed.
        What is amazing to me is that the scientific community has not
been able to convince itself of these conclusions, nor communicate them
to policy-makers.  Until that happens, why should we expect, or ask for
policies to change?

.