Healthy soil and sustainable growing

["Phil Bunch" <pbunch@cox.net>]

I agree with Paul that we can learn from traditional farming systems. I also
think that we are in a unique position to integrate what many cultures have
discovered over very long times with the more recent knowledge of soil
ecology. Some things will work well in given locations and others will not.
The knowledge sharing on lists like this will help us sort out what is
valuable and disseminate the information broadly.

Soil is a complex system. As in all complex systems there is a limit to what
we can know about the behavior of any given soil at any given time with any
given set of modifications. It's like the weather, the large number of
interacting variables leads to non-linear behavior. It is a mistake to think
about the soil as an object, it is a process.

That being said we do know a fair amount about how these processes behave
and what the components of the system are. For farming probably the most
important thing to understand is how to prevent erosion. We know that once a
soil is gone it is time consuming and expensive to recover good soil
functions. No-till is certainly a good erosion prevention practice. 

We know that in most native soils there is a diverse community of organisms
including, bacteria, fungi, insects, mites, nematodes and other worms as
well as many less well know critters. These form food chains mostly supplied
with energy from the sun via plants. The plants also use minerals in the
soil. The soil ecology is dominated by decomposition processes.

Diversity provides soils with resilience in the face of change. If a cow
drops a load at some point on a soil surface the conditions at that location
are drastically different than they were a few moments before the event. Not
all organisms are competent decomposers of cow dung. Those competent
organisms at or near the site suddenly have much better conditions, and
incompetents have much worse conditions. Soon however this imbalance is
resolved through a complex set of changes which eventually return to a state
similar to the pre-drop condition. The establishment of a nitrogen fixing
plant at a site also causes changes in the local conditions as does the fall
of a leaf. 

The long term application of tillage and massive nutrient inputs probably
results in a new, less diverse steady state. I don't have data on hand to
back this up but in ecology this is the typical outcome of frequently
repeated disturbance. Given time and the absence of such disturbance,
systems return to a steady state that often is similar to the original. 

The problem humans face is how to manage this system to their benefit, both
long and short-term. Tillage and the input of massive amounts of nutrients
are very big changes on a large scale and cause the soil to adapt to the
conditions they create. Natural changes are mostly small-scale and patchy.
This is a fundamental difference because the patchiness supports diversity
and resilience. Tillage, no-till and organic methods are all forms of
management. They affect the soil in different ways.

When it comes down to it, what we want from the soil is food in the largest
quantity consistent with sustainable production. We don't really want a
native soil because it does not provide the conditions we need to produce
crops. We do want to prevent erosion, reduce inputs of time and money and
harvest wholesome crops.

As is the case with any human endeavor we must clearly define our values and
goals if we want to achieve our mission. Once this is done we need to choose
the methods that best achieve what we want. My personal belief is that both
no-till and organic methods should be used together in an overall management
strategy. Use each as prescriptions for specific needs. (As some may recall
I also think there is a place for limited use of commercial fertilizers but
they are specific and should be seen as very short-term fixes that allow the
rapid application of sustainable means.)

I suspect that no-till or low till most closely approximates the conditions
of native soils and provides the greatest opportunities to maintain a
sustainable, productive, diverse and resilient soil. If this is the case a
long-term goal of no-till/low-till would be the way to go. I would use
organic methods to build toward this goal and to fix soil problems such as
low fertility should they occur. I suspect that organic methods probably
have greater short-term productivity but may expose the soil to erosion and
fairly substantial fluctuations with concomitant reductions in diversity.
Trade-offs may be necessary to reach and sustain goals.

There may be some locations where no-till methods would limit production in
such a way that it would not support our goals. I'm thinking about
constantly cool climates which need to have the soil exposed to sunlight to
warm it up. Very cool soils limit production substantially and greatly
reduce the crops that can be grown.

Phil Bunch

-----Original Message-----
From: livingontheland-bounces@lists.ibiblio.org
[mailto:livingontheland-bounces@lists.ibiblio.org] On Behalf Of
TradingPostPaul
Sent: Friday, December 14, 2007 7:57 PM
To: livingontheland@lists.ibiblio.org
Subject: Re: [Livingontheland] NO-TILL FARMING OFFERS A QUICK FIX TO
HELPWARD OFF HOST OF GLOBAL PROBLEMS


As you say, soil biology is quite complex and tilling definitely messes up
soil biology. Complete understanding of soil biology is way beyond the
state of our so-called science, so we're all in the same boat, aren't we.
So where do we go from here? How can we know anything? 

Let's put it this way: the theory may be difficult, but the growing is not.
 People without scientists the world over have used many different methods,
but the essential principles are the same in any language. 

paul tradingpost@lobo.net

*********** REPLY SEPARATOR  ***********

On 12/14/2007 at 7:00 PM Aliza wrote:

>So is he saying that he thinks organics should till?  organic No till is
>the ticket but you have to make sure the minerals are bioavailable to the
>plant.  It is not just as easy as popping your seeds into your last crop
>LOL.  I am not the most knowlegeable about this but I do know that the
>plants dont give up their goodies until they are dead and are best left in
>and on the soil to enrich the next crop.  Just because someone uses
>organic methods does not mean that the food they create will have high
>amounts of vitamins and minerals.  Soil biology is quite complex and
>tilling definately messes up soil biology.
>
>aliza
>  ----- Original Message ----- 
>  From: Marty Kraft 
>  To: Healthy soil and sustainable growing 
>  Sent: Friday, December 14, 2007 2:55 PM
>  Subject: Re: [Livingontheland] NO-TILL FARMING OFFERS A QUICK FIX TO
>HELPWARD OFF HOST OF GLOBAL PROBLEMS
>
>
>  Paul
>
>
>  I sent this article to a friend and am including his response in this
>email. Are we talking about commercial no-till vs an organic no-till
>methods here? My friend raises organic wheat and is conscientious in his
>work. 
>
>
>  Marty,
>
>  You had better check your facts on this. The way no-till makes the grade
>is by cheating on the soil tests. The main reason that KSU is behind this
>is to sell new farm equipment and make a name for mr. Charles Rice. There
>is more research showing that organic farming will sequester more carbon
>than ANY other form of farming. And another point, the no-till idea does
>NOT take into account the CO2 that gets released during the manufacturing
>of nitrate fertilizer. Of course, organic does not use manufactured
>fertilizer.
>
>  On Dec 10, 2007, at 6:16 PM, TradingPostPaul wrote:
>
>
>
>
>    NO-TILL FARMING OFFERS A QUICK FIX TO HELP WARD OFF HOST OF GLOBAL
>PROBLEMS
>    http://researchnews.osu.edu/archive/notill.htm
>
>
>    COLUMBUS, Ohio  Increase no-till farming practices across the
planet
>or
>    face serious climate, soil quality and food production problems in the
>next
>    20 to 50 years. That warning from scientists appeared in the journal
>    Science this week.
>    Rattan Lal
>
>
>    No-till farming helps soil retain carbon. Healthy topsoil contains
>    carbon-enriched humus  decaying organic matter that provides
nutrients
>    to plants. Soils low in humus can't maintain the carbon-dependent
>nutrients
>    essential to healthy crop production, resulting in the need to use
more
>    fertilizers.
>
>
>    A lack of carbon in soil may promote erosion, as topsoil and
>fertilizers
>    are often washed or blown away from farm fields and into waterways,
>said
>    Rattan Lal, the paper's lead author and the director of the carbon
>    management and sequestration center at Ohio State University.
>
>
>    In no-till agriculture, farmers plant seeds without using a plow to
>turn
>    the soil. Soil loses most of it carbon content during plowing, which
>    releases carbon dioxide gas into the atmosphere. Increased levels of
>CO2 in
>    the atmosphere have been associated with global climate change.
>
>
>    "If every farmer who grows crops in the United States would use
>no-till and
>    adopt management practices such as crop rotation and planting cover
>crops,
>    we could sequester about 300 million tons of soil carbon each year."
>
>
>    Traditional plowing, or tilling, turns over the top layer of soil.
>Farmers
>    use it for, among other reasons, to get rid of weeds, make it easier
>to use
>    fertilizers and pesticides and to plant crops. Tilling also enriches
>the
>    soil as it hastens the decomposition of crop residue, weeds and other
>    organic matter.
>
>
>    Still, the benefits of switching to no-till farming practices outweigh
>    those of traditional planting.
>
>
>    Since the mechanization of agriculture began a few hundred years ago,
>    scientists estimate that some 78 billion metric tons  more than 171
>    trillion pounds  of carbon once trapped in the soil have been lost
to
>    the atmosphere in the form of CO2.
>
>
>    Lal and his colleagues estimate that no-till farming is practiced on
>only 5
>    percent of all the world's cultivated cropland. Farmers in the United
>    States use no-till methods on 37 percent of the nation's cropland,
>which
>    results in saving an estimated 60 million metric tons of soil CO2
>annually.
>
>
>    "If every farmer who grows crops in the United States would use
>no-till and
>    adopt management practices such as crop rotation and planting cover
>crops,
>    we could sequester about 300 million tons of soil carbon each year,"
>said
>    Lal, who is also a professor of soil science at Ohio State.
>
>
>    "Each year, 6 billion tons of carbon is released into the planet's
>    atmosphere as fossil fuels are burned, and plants can absorb 20 times
>that
>    amount in that period of time," he said. "The problem is that as
>organisms
>    decompose and plants breathe, CO2 returns to the atmosphere. None of
it
>    accumulates in the soil."
>
>
>    Lal admits that full-scale no-till farming practices are a short-term
>fix,
>    but it's one that will give researchers enough time to find
>alternatives to
>    fossil fuels.
>
>
>    "There needs to be a global effort to adopt no-till farming practices
>soon.
>    Governments need to mandate these practices or to provide financial
>    incentives to farmers to adopt them," said Lal, adding no-till methods
>may
>    reduce a farmer's annual crop yield by 5 to 10 percent, at least for
>the
>    first few years.
>
>
>    It's also tough to ask farmers who lack the necessary financial
>resources
>    to switch to no-till methods, especially in African and Asian
countries
>    where no-till levels are the lowest, Lal said.
>
>
>    "No-till isn't readily practiced in most of these areas due to the
>lack of
>    available financial resources and government support," he said.
>"Farmers
>    often lack the seeding equipment necessary to drill through crop
>residue.
>    And many farmers use leftover residue from the previous year's crops
>for
>    fuel or animal fodder. So the cultivated soil gets compacted or eroded
>by
>    water and wind."
>
>
>    Topsoil is also a lucrative commodity  an acre of it can bring in
>$1,300
>    for a farmer in India, where the first few feet of soil are often
>removed
>    for brick making.
>
>
>    "No-till farming isn't a substitute for finding alternatives to fossil
>    fuels," Lal said.
>
>
>    "No-till is definitely a short-term fix, but it may buy us up to 50
>years
>    to find alternatives to fossil fuels. If we don't heed this warning,
>our
>    planet may change drastically. There's no other choice."
>
>
>    Lal co-authored the paper with Michael Griffin, Jay Apt, Lester Lave
>and M.
>    Granger Morgan, all with Carnegie Mellon University.
>
>
>
>
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>
>
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