This is almost an outbreak of common sense, but what is also clear is
that wind loss is possibly far less than the simple retention of a
stubble held boundary layer. Certainly the build up in the low
points appears to lessen.
All this leads to a more uniformly and better watered field and
represents one more compelling argument in favor of no till
agriculture.
Add in the judicious application of tree friendly fence rows to
prevent a build up of any significant surface winds and we soon
optimize the capture of winter snows.
In time we will surely get this right and it is delightful to
chronicle the ongoing effort to optimize agriculture methodology.
No-Till Farming
Helps Capture Snow and Soil Water
by Ann Perry
Pullman WA (SPX) Sep 05, 2012
Wheat stubble left
standing by no-till management helps generate a smoother snow cover,
which boosts dryland crop productivity in the summer, according to
new ARS research. Photo courtesy of ExactrixTM Global Systems.
A smooth blanket of
snow in the winter can help boost dryland crop productivity in the
summer, and no-till management is one way to ensure that blanket
coverage, according to U.S. Department of Agriculture (USDA)
research.
Agricultural Research Service
(ARS) soil scientist David Huggins conducted studies to determine how
standing crop residues affect snow accumulation and soil water levels
across entire fields. ARS is USDA's chief intramural scientific
research agency, and this work supports the USDA priority of
responding to climate change.
Huggins, who works at
the ARS Land Management and Water Conservation Research Unit in
Pullman, Wash., carried out this investigation on two neighboring
farms. Both farms have the hilly topography typical of the Palouse
region in eastern Washington. But much of one farm has been under
continuous no-till management since 1999, while the fields on the
other farm were conventionally tilled.
For
two years, snow depths, density and soil water storage
were measured manually at hundreds of points across the fields on
both farms. Residue height at data collection points was also
measured on the no-till fields.
Huggins found that
standing wheat residue on the no-till farm significantly increased
the amount and uniformity of snow cover across the entire field. Snow
depths on the no-till field ranged from 4 to 39 inches, with an
average depth of 11 inches, while snow depths on the conventionally
tilled field ranged from 0 to 56 inches, with an average depth of 8.5
inches.
The snow distribution
pattern on the no-till farm made soil water distribution more uniform
and increased soil water recharge rates there. The more uniform snow
distribution under no-till was particularly apparent for ridge tops
and steep south-facing slopes where there was typically 4 to 8 inches
more snow than on conventionally tilled fields.
Huggins
calculated that the greater storage of soil water in no-till systems
could increase winter wheat yield potential by 13
bushels per acre on ridge tops, six bushels per acre on south facing
slopes, and three bushels per acre in valleys. As a result, regional
farmers could increase their winter wheat profits by an average of
$30 per acre and as much as $54 per ridge-top acre.
Producers
affected by the 2012 drought might also benefit from using no-till to
increase the amount and uniformity of snow cover on their fields.
This would increase soil water recharge rates
and soil moisture storage, which would facilitate the
return of drought-stricken fields to their former productivity.
Results from this work
were published in 2011 in Transactions of the ASABE. Read more
about this study in the August 2012 issue of Agricultural
Research magazine.
ARS Land Managementand Water Conservation Research Unit
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