Proper Management Can Make Lower Yields
Profitable By Laura McGinnis July 9, 2007
In agriculture, less is sometimes more. That's the conclusion of
Agricultural Research Service (ARS)
scientists who discovered that reduced tillage can increase soil carbon, and
that lower corn yields can net higher profitsunder the right management.
Corn leaves a lot of crop residue, so many growers till fields
intensively when preparing soil for the next crop. To find out how tillage
affects greenhouse gas emissions, soil scientist
Halvorson with the
Soil Plant Nutrient Research Unit, Fort Collins, Colo., and Arvin Mosier,
formerly with ARS, measured trace gases being emitted from the soil in three
cropping systems: corn under conventional till and continuous no-till, and a
no-till corn-soybean rotation.
With several ARS colleagues, they found that when adequately
fertilized, no-till soils sequestered more carbon than conventionally tilled
soils, significantly reducing greenhouse gas emissions.
Halvorson and his colleagues also measured the effects of nitrogen
fertilization and tillageboth conventional and no-tillon irrigated
continuous corn yields. No-till management had multiple benefits, such as
reducing soil erosion and fossil fuel consumption, sequestering carbon in the
soil and lowering emission of greenhouse gases.
However, no-till also lowered yields by about 23 bushels per acre at
optimal nitrogen rate.
The initial results made conventional tillage look like the better
economic strategy, but further analysis revealed a surprising twist.
Archer, an ARS economist then located at the
Central Soil Conservation Research Laboratory, Morris, Minn., found that
no-till was actually more profitable than conventional tillage. Archer
is currently located at the
Great Plains Research Laboratory, Mandan, N.D.
Using a statistical model, Archer determined that no-till management
increased net profits by enabling significant reductions in tillage operations,
machinery and labor costs and fossil fuel consumption. Net savings were $83 per
acreenough to compensate for lower yields and still turn a profit.
The economic benefits for farmers using these conservation practices
could be even greater when participating in USDA conservation programs.
about the research in the July 2007 issue of Agricultural Research
ARS is the U.S. Department of
Agriculture's chief scientific research agency.