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CRP
Take-out Research:
RETUTNING
CRP LAND TO CROP PRODUCTION
CRP
Background in Washington State and Pacific Northwest
In
1995, the Pacific Northwest had over 2.5 million acres of cropland
in the Conservation Reserve Program (CRP). In Washington State there
were over 1.045 million acres of CRP land. This represented nearly
14% of the 7.6 million acres in a 20 county area of eastern Washington.
About 80% of the Northwest CRP contracts were scheduled to expire
in 1997, representing over 800,00 acres in Washington State alone.
A
majority of the CRP land in Washington and the Northwest is in the
low rainfall, winter wheat­summer fallow regions. These areas
typically receive from 7 to 14 inches annual precipitation and are
susceptible to wind erosion, as well as water erosion. Serious soil
erosion problems could result if intensive tillage and residue removal
practices are used to return CRP land to crop production.
Overview
of the Washington State CRP Take­out Research Project
A
Washington State research project was initiated in 1994 to evaluate
management strategies for returning CRP land to crop production.
It was designed as an umbrella project for a comprehensive, "grass
roots" effort to evaluate prospective, locally­identified
management options for specific agronomic zones of the state. The
research focus was on the low-rainfall, crop-fallow region where
much of the CRP land was located. Crested wheatgrass is the predominant
CRP grass in this area.
Washington
State University Cooperative Extension was responsible for coordinating
the statewide CRP take-out research project, as authorized by the
Washington Farm Service Agency (FSA). The project relied on active
involvement of growers, extension specialists and agents, researchers,
and personnel from agricultural support agencies and industry.
The
project goal was to identify management strategies that optimize
agronomic performance and profitability of the first crops following
CRP take-out, while providing effective soil erosion control and
preserving soil improvements gained during CRP. There were two primary
research thrusts in this statewide project: 1) evaluate management
strategies for returning CRP land to winter wheat production following
summer fallow; and 2) evaluate management strategies for returning
CRP land to spring crop production.
Criteria evaluated to determine the relative success of different
CRP take-out systems included: soil water storage efficiency; crop
establishment and development; soil erosion potential; pest incidence;
crop yield and quality; and economics.
This
research project was funded in part by two grant programs from the
USDA Cooperative States Research, Extension and Education Service
(CSREES) through WSU: STEEP II (Solutions To Environmental and Economic
Problems) and the Columbia Plateau Wind Erosion/Air Quality Project.
Research Approach
Before
field experiments were initiated, a series of local planning meetings
were conducted in six counties with high CRP acreage. Each meeting
included four to six growers, county extension agents, researchers
and personnel from USDA­NRCS, conservation districts and the
agricultural service industry. This group identified prospective
tillage and residue management systems to be studied in the CRP
take-out field research trials. The tillage systems in most 1994
and 1995 trials relied primarily on commonly available tillage equipment
within the different cropping regions. Direct seeding was also evaluated
in one 1995 field trial in Columbia County and in three 1996 field
trials in Adams and Douglas Counties.
This
field research project used the large-scale, replicated, on-farm
testing approach with farm­scale equipment operated by the growers.
This approach increases grower confidence in the research results
and facilitates rapid grower adaptation of research results. Treatment
areas for each plot were generally 30 to 50 Feet wide, depending
on the implements used, and 800 to 1,000 feet long. Each treatment
was replicated four times. Most trials included 4 to 6 management
systems (treatments) and were 12 to 30 acres.
The
project leaders and cooperators worked with growers to design and
lay out the field experiments, and collecting the data. The growers
performed all of the crop production operations. Yield measurements
are made using the grower's combine and portable truck scales or
weigh wagons.
Data
collection included initial grass biomass, soil water content in
the spring and at fall planting, soil fertility analysis for fertilizer
application, surface residue cover and surface roughness for evaluating
soil erosion potential, pest incidence, plant stands, and crop yield.
Comparative crop enterprise budgets were generated to evaluate the
profitability of the different systems. Some of the trials were
followed through the next crop rotation to evaluate the long term
effects of take-out treatments on soil erosion potential, pest incidence
and soil quality.
In
cooperation with other university and industry researchers, experiments
were also conducted to evaluate alternative spring crop choices,
fertility management in CRP take-out, nonselective herbicide rates
and timings for killing CRP grass before direct seeding, root disease
interactions, soil quality effects, and economic analysis of different
take-out systems.
Overview
of Field Trials
Ten
large-scale on-farm trials were conducted, primarily in crested
wheatgrass CRP fields. Three trials in Adams, Franklin, and Lincoln
Counties evaluated different tillage and residue management systems
for CRP takeout with summer fallow and were planted to winter wheat
in 1995. Spring take-out trials for spring wheat were completed
in Columbia County in 1994 and 1995, along with a small plot satellite
study on spring crop choice under high and low residue systems in
1995. A direct seeding trial with spring barley was also conducted
in Columbia County in 1995. Four small plot research trials on non-selective
herbicide use for killing CRP grasses were conducted in Franklin
and Adams Counties in 1994-95 by Monsanto. Another study on nonselective
herbicide use in CRP take-out was conducted by the McGregor Company
in 1995, adjacent to a large scale trial in Columbia County.
Three
trials on spring take-out with hard red spring wheat were conducted
in 1996. Each trial compared 3-5 direct seeding systems with a tillage
comparison. Two were located near Ritzville and one near Waterville.
A fourth spring 1996 take-out trial evaluated several tillage and
residue management systems for spring barley in tall wheatgrass
CRP near Sprague.
Summary
Publication and More Information on CRP Take-out
Detailed
summaries of the CRP take-out project research findings and management
strategy considerations are available in PNW Conservation Tillage
Handbook Series No. 16a in Chapter Two. It is available from the
Crop and Soil Sciences Dept. Cooperative Extension office, Washington
State University, Pullman, WA 99164-6420, (509-335-2915), or contact
Roger Veseth at 208-885-6386
(e-mail: rveseth@uidaho.edu). This Handbook Series can also be accessed
on the Internet (http://pnwsteep.wsu.edu).
Concepts
described in this report were provided by Roger Veseth, Washington
State University/University of Idaho Conservation Tillage Specialist,
during a seminar held in Ritzville, WA on October 18, 1996. Prepared
by John D. Fouts, WSU Cooperative Extension.
Agricultural
Sustainability. Highlights from a seminar series conducted by Washington
State University's Ag Horizons Team and funded by USDA Western Region
SARE.
John
D. Fouts
222 N. Havana
Spokane, WA 99202-4799
Phone: (509) 477-2176
FAX: (509) 477-2087
 fouts@wsu.edu
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