In article
<486f3c4f$0$3084$5a62ac22@[EMAIL PROTECTED]
>,
"FarmI" <ask@[EMAIL PROTECTED]
be given> wrote:
> "Billy" <wildbilly@[EMAIL PROTECTED]
> wrote in message
> > "FarmI" <ask@[EMAIL PROTECTED]
be given> wrote:
> >> "Billy" <wildbilly@[EMAIL PROTECTED]
> wrote in message news:wildbilly-
> >>
> >> As you will see, industrial no-till was introduced
> >> > to combat the erosion and loss of top soil. But industrial no-till
> >> > relies on expensive chemical inputs of fertilizers and increasing
> >> > quantities of chemical remedies to combat pests (vegetative and
insect
> >> > problems)
> >>
> >> I think your post is a bit too broad in it's scope.
> >>
You be the judge (as if it could be anyother way;-)
This is the pertinent, last half of the article.
------
Extract form July, 2008, Scientific American
No-Till: the Quiet Revolution
By David R Huggins and John P Reganold
Pg. 70
Betting the Farm
No-till and other conservation till systems can work in a wide range of
climate, soils, and geographic areas. Continuous no-till is applicable
to most crops, with the notable exceptions of wetland rice and root
crops, such as potatoes. Yet in 2004, the most recent year for which
data are available, farmers were practicing no-till on only 236 million
acres world wide - not even 7 percent of total global cropland.
Of the top five countries with areas under no-till, the U.S. ranks first
followed by Brazil, Argentina, Canada and Australia. About 85 percent of
this no-till land lies North and South America. In the US roughly 41
percent of all planted cropland was farmed using conservation tillage
systems in 2004, compared with 26 percent in 1990. Most of that growth
came from expanded adoption of no-till, which more than tripled in that
time, to the point where it was practiced on 22 percent of U.S.
farmland. This no doubt partly reflects the fact that U.S. farmers are
encouraged to meet the definition of conservation tillage to participate
in government subsidy and other programs. In South America, adoption of
no-till farming has been relatively rapid as a result coordinated
efforts by university agricultural-extensions educators and local farm
communities to develop viable no-till cropping systems tailored to their
particular needs.
On the other hand, adoption rates are low in Europe, Africa and most
parts of Asia Embracing no-till has been especially difficult in
developing countries in Africa and Asia because farmers there often use
the crop residues for fuel, animal feed and other purposes. Furthermore,
the specialized seeders required for sowing crops and the herbicides
needed for weed control may not be available or can be prohibitively
expensive for growers in these parts of the world. Meanwhile, in Europe,
an absence of government policies promoting no-till, along with elevated
restrictions on pesticides (including herbicides), among other
variables, leaves farmers with little incentive to adopt this approach.
Changing from tillage-based farming to no-till is not easy. The
difficulty of the transition, together with the common perception that
no-till incurs a greater risk of crop failure or lower net returns than
conventional agriculture, has seriously hindered more widespread
adoption of this approach. Although farmers accept that agriculture is
not a fail-safe profession, they will hesitate to adopt a new farming
practice if the risk of failure is greater than in conventional
practice. Because no-till is a radical departure from other farming
practices, growers making the switch to no-till experience a steep
learning curve. In addition to the demands of different field practices,
the conversion has profound impacts on farm soils and fields. Different
pest species can arise with the ****ft from tillage-based agriculture to
no-till, for instance. And the kinds of weeds and crop diseases can
change. For example, the elevated moisture levels associated with
no-till can promote soil-borne fungal diseases that tillage previously
kept in check. Indeed, the discovery of new crop diseases has sometimes
accompanied the ****ft to no-till.
Some of the changes that follow from no-till can take years or even
decades to unfold, and farmers need to remain vigilant and adaptable to
new, sometimes unexpected, situations, such as those that arise from
****fts in soil and residue conditions or fertilizer management. During
this transition, there is a real risk of reduced yields and even failed
crops. In the Palouse (farm in Wa****ngton State), for example, some
farmers who attempted no-till in the l98Os are no longer in business.
Consequently, farmers looking to switch to no-till should initially
limit the converted acreage to 10 to 15 percent of their total farm.
Farmers who are new to no-till techniques often visit successful
operations and form local or regional sup****t groups, where they share
experiences and discuss specific problems. But the advice they receive
in areas with limited no-till adoption can be incomplete or
contradictory, and gaps in knowledge, experience or technology can have
potentially disastrous outcomes. If the perception that no-till is
riskier than conventional techniques develops in a farming community,
banks may not underwrite a no-till farmer's loan. Alternatively, growers
who are leasing land may find that the owners are opposed to no-till
because of fears that they will not get paid as much. Improving the
quality of information exchange among farmers, universities,
agribusinesses and government agencies will no doubt go a long way
toward overcoming these obstacles.
Yet even in the hands of a seasoned no-till farmer, the system has
drawbacks. No-till crop production on fine-textured, poorly drained
soils can be particularly problematic, often resulting in decreased
yields. Yields of no-till corn, for instance, are often reduced by 5 to
10 percent on these kinds of soils, compared with yields with
conventional tillage, particularly in northern regions. And because the
crop residue blocks the sun's rays from warming the earth to the same
degree as occurs with conventional tillage, soil temperatures are colder
in the spring, which can slow seed germination and curtail the early
growth of warm-season crops, such as corn, in northern latitudes.
In the first four to six years, no-till demands the use of extra
nitrogen fertilizer to meet the nutritional requirements of some crops,
too-up to 20 percent more than is used in conventional tillage
systems-because increasing organic matter at the surface immobilizes
nutrients, including nitrogen. And in the absence of tillage, farmers
depend more heavily on herbicides to keep weeds at bay.
Herbicide-resistant weeds are already becoming more common on no-till
farms. The continued practice of no-till is therefore highly dependent
on the development of new herbicide formulations and other weed
management options. Cost aside, greater reliance on agrichemicals may
adversely affect non-target species or contaminate air, water and soil.
Integrating No-Till
No-till has the potential to deliver a host of benefits that are
increasingly desirable in a world facing population growth,
environmental degradation, rising energy costs and climate change, among
other daunting challenges. But no-till is not a cure-all; such a thing
doesn't exist in agriculture. Rather it is part of larger, evolving
vision of sustainable agriculture, in which a diversity of farming
methods from no-till to organic-and combinations there of-is considered
healthy. We think that ultimately all farmers should integrate
conservation tillage, and no-till if feasible, on their farms.
Future no-till farming will need to employ more diverse pest and weed
management strategies, including biological, physical and chemical
measures to lessen the threat of pesticide resistance. Practices from
successful organic farming systems may be instructive in that regard.
One such technique, crop rotation-in which farmers grow a series of
different crops in the same space in sequential seasons-is already
helping no-till's war on pests and weeds by helping to break up the
weed, pest and disease cycles that arise when one species is
continuously grown.
To that end, the capacity to grow a diverse selection of economically
viable crops would advance no-till farming and make it more appealing to
farmers. But the current emphasis on corn to produce ethanol in the
Midwestern Corn Belt, for instance, is promoting monoculture-in which a
single crop, such as corn, is grown over a wide area and replanted every
year-and will likely make no-till farming more difficult in this region.
Experts continue to debate the merits of growing fuel on farmland, but
if we decide to proceed with bio-fuel crops, we will need to consider
using no-till with crop rotation to produce them sustainability.
Development of alternative crops for bio-energy production on marginal
lands, including perennials such as switchgrass, could complement and
promote no-till farming, as would perennial grain food crops currently
under development [see "future Farming: A Return to Roots?" by Jerry 1).
Glover, Cindy M. Cox and John P. Reganold; Scientific American, August
2007].
Today, three decades after first attempting no-till on his Palouse farm,
John Aeschliman uses the system on 100 percent of his land. His adoption
of no-till has followed a gradual, cautious path that has helped
minimize his risk of reduced yields and net returns. Consequently, he is
one of many farmers, large and small, who is reaping the rewards of
no-till farming and helping agriculture evolve toward sustainability.
--
Billy
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