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VII. Policy Impacts on Crop Rotations
D. L. KARLEN ET AL.
Iowa Farmer AttitudesUwith Regard to the Statement
“A Good Cropping System Should Include Rotations of Small Grains
or Forage Along with Row Crops”
* Information provided by Dr. Steve Padgitt, Iowa State University. Ames,
Iowa, from a survey associated with participants and nonparticipants in Iowa
State University’s Integrated Crop Management (ICM) research program.
ICM cooperators included those persons in Caroll, Kossuth, and Sioux
Counties who had participated in a Model Farms program with Iowa State
University. Neighbors are persons living adjacent to a coopcrator. Random
includes persons living in those counties.
L‘ In these counties 14% of the cooperator group had small grains or forages
in addition to row crops. Among neighbors and participants in the random
sample, 50% had small grains or forages in addition to row crops.
Concerns about environmental impacts have been peripheral to date, but questions regarding agricultural policy impacts on practices such as crop rotations are
being asked more frequently. Factors including production surpluses, rising commodity program costs, and environmental degradation are encouraging a reexamination of current programs (Moore, 1989).
Participation in U.S. agricultural commodity programs has generally resulted
in decisions to use more erosive crop rotations (Poe et al., 1991). This has tended
to occur because under conditions of program participation, on-site and off-site
erosion costs that can affect crop rotation decisions have been internalized.
Therefore, these factors influence field-scale management decisions only when
long time periods (>40 years) are considered. The implications of crop rotation
on susceptibility of the Texas High Plains to wind erosion and groundwater
depletion were evaluated by Lee et al. (1989). Their simulations indicated that
farm program participation, coupled with base acreage restrictions, encouraged
production of continuous cotton. They projected that average annual wind erosion under continuous cotton would be two to six times greater than with alternate cropping systems. However, compliance with base acreage restrictions prior
to the 1985 Food Security Act limited adoption of multiyear or multicrop production systems. Changes in policy were viewed as supporting 2-year rotations such
as cotton and wheat or 3-year rotations such as cotton, sorghum, and wheat, both
of which provide substantial wind erosion control.
Until recently, agricultural policy has reflected goals of increased farm and
CROP ROTATIONS FOR THE 2 1st CENTURY
rural income, low-cost food, improved rural conditions, improved technical efficiency of farming operations, and natural resource conservation as part of the
agricultural productivity base (Doering, 1992). At times, programs designed to
enhance the various goals have conflicted. Furthermore, the market often fails to
alert agricultural producers to the real costs associated with on-site and off-site
environmental damage (Doering, 1992).
Agricultural policies, however, provide only one part of a farmer’s decision
framework. Other factors include the relative costs associated with alternatives
such as tractors vs draft animals, fertilizers vs manure, and pesticides vs cultivation. Nonfarm policies that affect the economy, trade, industry structure, resources, and the environment can also have more impact on the way farmers
manage their land than official agricultural policy (Doering, 1992). He also states
that national decisions about health, safety, and environmental quality have had
and will continue to have a great influence on the way farmers farm. From this
perspective, Doering (1992) concludes that federal policies toward agriculture do
not appear to provide an incentive or disincentive for less intensive and more
environmentally benign agricultural practices and cropping systems. He suggests
that new policy approaches should target specific management practices, cropping patterns, input use, or sensitive locations. This approach will require new
policy mechanisms to deal specifically and equitably with environmental concerns and society’s changing values, while recognizing actual production decisions that farmers face daily.
In a report compiled from 12 interviews with agricultural policy-making individuals in Washington, D.C., Moore (1989) found that crop rotations, in principle, were viewed as beneficial for American agriculture. However, unqualified
support for a crop rotation policy was not expressed. The primary concerns were
focused on how uncontrollable conditions, such as international market prices or
drought, would impact successful implementation of a crop rotation policy.
Two perspectives that emerged from the interviews were a desire to deter
monocropping practices and concern for maintaining farm incomes (Moore,
1989). The first perspective focused on total resource efficiency for society as a
whole and emphasized benefits to be gained by encouraging crop rotations.
These benefits included improved soil and water quality, increased farm flexibility, reduced program costs, increased diversity, reduced dependence on nitrogen fertilizers, reduced chemical input costs, and reduced insect pests. The
second perspective emphasized known benefits of crop rotation to individual
producers, i.e., maintaining productivity at the microeconomic level. To be
effective, crop production or land use subsidies would be needed to compensate
farmers for using crop rotations (Moore, 1989). Information and education regarding site-specific crop rotation practices and impacts, profitability of rotated
crops, market infrastructures for new crops, an integration of new livestock
production practices, new equipment, and reduced exports are some needs iden-
D. L. KARLEN ET AL.
tified as being crucial for increased adoption of crop rotations as we enter the 2 1st
Potential incentives to encourage crop rotation include monetary compensation, long-term program stability, provision of appropriate knowledge and skills,
and development of market infrastructure for various new crops (Moore, 1989).
Several disincentives for continuing monoculture include regulations, liabilities
for on-site and off-site damages, and internalization of external costs. It was
suggested to Moore ( 1 989) that crop rotations could be required under certain
site-specific circumstances and that routine groundwater monitoring might be
required. The projected impacts of crop rotation policies were that corn would be
less widely distributed, especially in nontraditional corn-growing areas. Farm
labor and management requirements would increase-perhaps increasing opportunities for rural employment. General environmental quality would improve,
although changes could not be guaranteed. Improved rural aesthetics, increased
requirements for educational and training programs, and some redistribution of
income among companies as they develop uses and markets for alternative crops
would be expected. There would also be increased demand for production consultants and a probable reduction in the volume of U.S. exports. However,
international prices may rise and actually result in higher export earnings.
Changing current agricultural policy to accommodate crop rotations would
focus on the core of policy issues by raising questions regarding the ultimate
goals for U.S. agriculture (Moore, 1989). When determined, costs and benefits
of the alternatives, trade-offs, and impacts of all aspects must be resolved to
establish a solid basis for policy consensus. When this is accomplished, the
policy stage will be set for encouraging and facilitating adoption of crop rotations
in farm management practices.
VIII. SUMMARY AND CONCLUSIONS
Advantages and disadvantages of crop rotation have undoubtedly been debated
for thousands of years, as documented by historians (White, 1970b) who have
stated that rotation systems were widely recommended by Roman agronomists,
but often not adopted by local farmers. One reason for farmer hesitancy to use
crop rotation may be that agricultural scientists are still unable to explain the
mysterious “rotation effect.”
Macroeconomic and microeconomic considerations have and presumably will
always influence land use decisions, such as adoption of crop rotation. For the
U.S. corn belt, this was well documented by Wiancko (1927), but economic
considerations must include a more complete accounting for both on-site and offsite impacts of our soil and crop management practices.
CROP ROTATIONS FOR THE 2 1st CENTURY
Benefits of crop rotation for land and water resource protection and productivity have been identified, but processes and mechanisms responsible for those
benefits need to be better understood. This is a critical area for basic and applied
research. Public policies that influence land use decisions, such as crop rotation,
need to be as flexible as possible to encourage adoption of practices that are
economically viable, environmentally sustainable, and socially acceptable. Following this agenda will ensure that crop rotations have a major role in 21st
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