**Accomplishment Report**

**(2002-2006)**

**National Program 207, Integrated Agricultural Systems**

**Agricultural Research Service**

**U.S. Department of Agriculture**

**July 6, 2006**

**Table of Contents**

[Introduction 5](#introduction)

[Research Goal I. Enhanced Capacity to Solve Problems Using System
Research Approaches.
7](#research-goal-i.-enhanced-capacity-to-solve-problems-using-system-research-approaches.)

[A. Problem Area. Systems Research Attributes Assessment
7](#__RefHeading___Toc147540270)

[1. Customer Involvement 7](#__RefHeading___Toc147540271)

[2. Research Approach 7](#__RefHeading___Toc147540272)

[3. Measured Assessments 8](#__RefHeading___Toc147540273)

[B. Problem Area. Research Impact Assessment
12](#__RefHeading___Toc147540274)

[1. Technology Transfer 12](#__RefHeading___Toc147540275)

[2. Impact of research on farm income 13](#__RefHeading___Toc147540276)

[3. Quality of Research Outcome 13](#__RefHeading___Toc147540277)

[4. Impact on Policies or Competitiveness in the Market
14](#__RefHeading___Toc147540278)

[Research Goal II. Enhanced Economic Opportunities for Agricultural
Producers and Rural Communities.
14](#research-goal-ii.-enhanced-economic-opportunities-for-agricultural-producers-and-rural-communities.)

[Problem Area A. Strategies to Reduce Production Costs and Increase
Profit.
14](#problem-area-a.-strategies-to-reduce-production-costs-and-increase-profit.)

[1. Conservation Tillage 14](#__RefHeading___Toc147540281)

[Expansion of conservation systems research project leads to technology
transfer initiatives 14](#__RefHeading___Toc147540282)

[Effect of landscape position on crop yield when transitioning from
conventional to conservation tillage systems
15](#__RefHeading___Toc147540283)

[No-tillage allows more intensive and flexible dryland cropping systems
and improves soil quality 15](#__RefHeading___Toc147540284)

[Conservation practices improve soil, air, & water quality and increase
profits in perennial grass seed production systems
15](#__RefHeading___Toc147540285)

[Reduced tillage in potato production systems
16](#__RefHeading___Toc147540286)

[Developing a strip tillage system for small seeded crops
16](#__RefHeading___Toc147540287)

[Conservation tillage and cover crop benefits for cotton and soybeans
17](#__RefHeading___Toc147540288)

[Systems approach improves adoption of conservation tillage systems in
the Southeastern U.S.A 17](#__RefHeading___Toc147540289)

[Increasing Adoption of Conservation Tillage Technology in the Tennessee
Valley Region 18](#__RefHeading___Toc147540290)

[Conservation tillage systems for hot and dry climates
18](#__RefHeading___Toc147540291)

[2. Rotation Crop Sequences 19](#__RefHeading___Toc147540292)

[Diversifying crop rotations and reducing tillage can reduce risk to
Northern Corn Belt farmers 19](#__RefHeading___Toc147540293)

[Dynamic systems approach to rotation crop selection
19](#__RefHeading___Toc147540294)

[3. Cover Crops, Crop Residues, and Manure Use
20](#__RefHeading___Toc147540295)

[Cover crop-based production system may be a potential alternative to
methyl bromide 20](#__RefHeading___Toc147540296)

[Utilizing fall-planted cover crops for weed suppression in potato
production systems 21](#__RefHeading___Toc147540297)

[Cover crops enhance date production 21](#__RefHeading___Toc147540298)

[Evaluation of novel cover crops 21](#__RefHeading___Toc147540299)

[Cover crop roller technology may be a key component of conservation
systems 22](#__RefHeading___Toc147540300)

[Discovering the molecular mechanisms that cover crops influence in
production systems 22](#__RefHeading___Toc147540301)

[Residue management attachment developed for no-till drills
22](#__RefHeading___Toc147540302)

[4. Integrated Practices to Minimize Pest Impacts
23](#__RefHeading___Toc147540303)

[Regional efforts to reduce weed pressures in the Pacific Northwest
23](#__RefHeading___Toc147540304)

[Small grain cover crops reduce the need for herbicide applications
23](#__RefHeading___Toc147540305)

[Cropping practices and rotations reduce the negative impact of weeds in
potato production systems 23](#__RefHeading___Toc147540306)

[Management strategies in rotation crops reduce populations of volunteer
potato 24](#__RefHeading___Toc147540307)

[Integrated management strategies reduce jointed goatgrass in the
Pacific Northwest 24](#__RefHeading___Toc147540308)

[No-till spring cropping system decreases downey brome populations
25](#__RefHeading___Toc147540309)

[Development of a biointegrated production system for strawberries
eliminates the need for fumigation 25](#__RefHeading___Toc147540310)

[Many approaches used together can increase New England agriculture
profitability 25](#__RefHeading___Toc147540311)

[Development of a PCR protocol for rapid detection of *Cercospora
beticola* 26](#__RefHeading___Toc147540312)

[Safflower is a secondary host of *Cercospora beticola*
26](#__RefHeading___Toc147540313)

[Alley cropping of alfalfa reduces need for insecticides, thus
increasing profitability potential 27](#__RefHeading___Toc147540314)

[Conservation tillage with a rye cover crop reduces thrips populations
in Southeast USA cotton 27](#__RefHeading___Toc147540315)

[5. Overcoming Limited Water Availability
27](#__RefHeading___Toc147540316)

[Optimization of crop performance through the proper water resource
management 27](#__RefHeading___Toc147540317)

[Feedback sensor systems for real time water management and
self-propelled irrigation system decision support
28](#__RefHeading___Toc147540318)

[Decision support systems for irrigation scheduling in peanuts, corn,
and cotton to improve profits and adoption
28](#__RefHeading___Toc147540319)

[Reduced supplemental irrigation in three Southeastern conservation
tillage systems 29](#__RefHeading___Toc147540320)

[Nitrogen and irrigation best management practices for potatoes on
coarse textured soils 29](#__RefHeading___Toc147540321)

[6. Precision Management Approaches 29](#__RefHeading___Toc147540322)

[Development of tools to rapidly assess crop status
30](#__RefHeading___Toc147540323)

[Sub-field management zones for improved crop nutrient utilization
30](#__RefHeading___Toc147540324)

[Mapping soil compaction to identify field areas for precision tillage
31](#__RefHeading___Toc147540325)

[Soil maps guide soil sampling for microbial properties
31](#__RefHeading___Toc147540326)

[Mapping soil electrical conductivity to understand sub-field grain
production variability 31](#__RefHeading___Toc147540327)

[Sensing technology to improve nitrogen application accuracy
32](#__RefHeading___Toc147540328)

[Sensing technology for improved soil compaction measurements
32](#__RefHeading___Toc147540329)

[Sensing to improve nitrogen application accuracy
32](#__RefHeading___Toc147540330)

[Understanding within-field grain yield variability
33](#__RefHeading___Toc147540331)

[Experimental designs for large commercial field precision applications
33](#__RefHeading___Toc147540332)

[Development of Site-Specific N Indices for Precision N Management
33](#__RefHeading___Toc147540333)

[7. Integrating crops and livestock for best benefits
34](#__RefHeading___Toc147540334)

[Integrated crop--livestock production systems for the southeastern U.S
34](#__RefHeading___Toc147540335)

[Tillage requirements for winter-annual grazing rotations
34](#__RefHeading___Toc147540336)

[Modified hay production system improves ruminant feed intake
35](#__RefHeading___Toc147540337)

[Improved pasture utilization increases dairy cow feed efficiency
35](#__RefHeading___Toc147540338)

[Tannins may increase dairy profits and enhance environmental quality
36](#__RefHeading___Toc147540339)

[Integrating annual forages into a Great Plains beef production system
36](#__RefHeading___Toc147540340)

[Dairy herd management enhances nutrient cycling
36](#__RefHeading___Toc147540341)

[On-farm research improves nutrient management on dairy farms
37](#__RefHeading___Toc147540342)

[Refined dairy diets enhance profits and the environment
37](#__RefHeading___Toc147540343)

[Problem Area B. Systems, Strategies, and Tools to Reduce Agricultural
Risks 37](#__RefHeading___Toc147540344)

[1. Alternative Risk-Aversion Production Systems
38](#__RefHeading___Toc147540345)

[Reducing tillage and diversifying crop rotations can reduce risk to
Northern Corn Belt farmers 38](#__RefHeading___Toc147540346)

[Designing low-risk dryland cropping systems for the Northern Great
Plains 38](#__RefHeading___Toc147540347)

[Holistic approach to farm planning and conservation programs improves
profitability and enhances natural resources conservation
39](#__RefHeading___Toc147540348)

[2. Models to Predict At-Risk Conditions and Best Responses to
Management 39](#__RefHeading___Toc147540349)

[Crop damage assessment tool for field-scale decisions
39](#__RefHeading___Toc147540350)

[Research results used to identify profitable combinations of potato
cropping practices for the Northeastern U.S.
39](#__RefHeading___Toc147540351)

[Crop simulation for decision making in Pacific Northwest potato-based
cropping systems 40](#__RefHeading___Toc147540352)

[On-farm research results in simple spreadsheet planning tools
40](#__RefHeading___Toc147540353)

[The economics of crop rotation sequences and technology transfer to
producers 40](#__RefHeading___Toc147540354)

[Producers can evaluate the 100 different crop sequences for the
Northern Great Plains 41](#__RefHeading___Toc147540355)

[Decision aids provide guidance to improve production efficiency,
reducing input costs, and increase profitability
41](#__RefHeading___Toc147540356)

[Interactive decision aid developed to estimate stem rust disease
development 41](#__RefHeading___Toc147540357)

[How and why weeds differ between fields and among years
42](#__RefHeading___Toc147540358)

[GLYCIM model increases irrigation efficiency for Mississippi Delta
soybean growers 42](#__RefHeading___Toc147540359)

[The latest scientific knowledge and technology incorporated into GOSSYM
and GLYCIM 42](#__RefHeading___Toc147540360)

[Agricultural system-level models used to help direct field research
43](#__RefHeading___Toc147540361)

[Generic interface for crop simulation models simplifies model use for
growers and scientists 43](#__RefHeading___Toc147540362)

[Web-based planning tools for conservation managers
43](#__RefHeading___Toc147540363)

[Problem Area C. Strategies to Expand Market Opportunities.
44](#problem-area-c.-strategies-to-expand-market-opportunities.)

[1. Producing Organic Products 44](#__RefHeading___Toc147540365)

[Manure use can be managed to benefit soil biodiversity and reduce
potential health risks 44](#__RefHeading___Toc147540366)

[Improved understanding of disease management in organic potato systems
helps all producers 44](#__RefHeading___Toc147540367)

[Organic management practices and soil biological responses
45](#__RefHeading___Toc147540368)

[Organic alternatives for deworming sheep and goats
45](#__RefHeading___Toc147540369)

[Increasing crop rotation length and complexity reduces weed pressure
and increases crop yields in organic systems
45](#__RefHeading___Toc147540370)

[First Low-Soil Disturbance Organic Cropping System Designed and Tested
in Pacific Northwest
46](#first-low-soil-disturbance-organic-cropping-system-designed-and-tested-in-pacific-northwest)

[Cover cropping practices improve organic weed management
46](#__RefHeading___Toc147540372)

[Factors of organic production affect cover crops and vegetables
47](#__RefHeading___Toc147540373)

[Stale seed bed techniques for organic vegetable production
47](#__RefHeading___Toc147540374)

[Modified crops for use in organic production systems
47](#__RefHeading___Toc147540375)

[Organic log-grown shiitake mushrooms contain health-promoting
polysaccharides 48](#__RefHeading___Toc147540376)

[2. Integrating agricultural-based energy production
48](#__RefHeading___Toc147540377)

[Sustainable production of bio-fuel crops
48](#__RefHeading___Toc147540378)

[Technology development for farm--scale conversion of straw to energy
48](#__RefHeading___Toc147540379)

[3. New Products from Agricultural Lands
49](#__RefHeading___Toc147540380)

[Important criteria defined for the design and management of temperate
silvopasture practices 49](#__RefHeading___Toc147540381)

[Eastern red cedar and chestnuts are attractive alternative crops for
small farmers 50](#__RefHeading___Toc147540382)

[Cuphea as a new oilseed crop for Northern Corn Belt
50](#__RefHeading___Toc147540383)

[Small-Scale Farmers Can Receive Income from Pine Straw Without
Increasing Soil Erosion 50](#__RefHeading___Toc147540384)

[High tunnel research capacity established to serve mid-Atlantic small
farmers 51](#__RefHeading___Toc147540385)

[Research Goal III. Protected and Enhanced Natural Resources on Farms
51](#research-goal-iii.-protected-and-enhanced-natural-resources-on-farms)

[Use of remote sensing and ground-truth surveys to monitor soil
disturbance and land use patterns across landscapes
51](#__RefHeading___Toc147540387)

[Identifying management practices that optimize economic and
environmental benefits at the watershed scale level
52](#__RefHeading___Toc147540388)

[Wildlife habitat impacts agricultural drainage water to constructed
wetlands 52](#__RefHeading___Toc147540389)

[Importance of considering environmental impacts of drainage ditch
management 52](#__RefHeading___Toc147540390)

[Grass seed farming landscapes provide excellent fish and wildlife
habitat 53](#__RefHeading___Toc147540391)

[Management schemes for alley cropping practices improve dove habitat
53](#__RefHeading___Toc147540392)

[Peer Review Publications 55](#peer-review-publications)

[Non-Peer Reviewed Publications 90](#non-peer-reviewed-publications)

[Book Chapters: 117](#book-chapters)

[LOCATIONS 121](#__RefHeading___Toc147540396)

# 

# 

# 

# 

#  Introduction

**National Program 207, Integrated Agricultural Systems**

Participants at many USDA-ARS Customer Workshops have expressed the need
for multidisciplinary systems research solutions to their problems. The
meeting of this need was formally put into place with holding the
USDA-ARS NP-207 Customer Workshop December 7-9, 1999 in Denver,
Colorado. A range of customers and partners participated, including
conventional and organic farmers, members of commodity organizations,
USDA-NRCS, tribal representatives, farm equipment manufacturers,
fertilizer dealers, and various advocacy groups, including the
Sustainable Agriculture Coalition and Center for Rural Affairs.

The primary customer outcome from the Denver workshop was a list of
specific attributes that ARS research should include when conducting
integrated agricultural systems research. In brief, a philosophy for
conducting research was outlined. Among the distinguishing features
integrated agricultural systems research should emphasize were:

-   Stakeholders should participate in the research process from project
    design to completion,

-   On-farm research approaches should be preferred over experiment
    station plots,

-   A spectrum of agricultural approaches, management strategies, and
    philosophies should be included in the research,

-   Multiple factors should be considered at the same time,

-   Agricultural production should be viewed within a larger holistic
    system that also includes environmental, economic, and sociological
    components,

-   Information transfer should be facilitated through regular
    interactions of the researchers with customers and stakeholders,

-   Experiments should be conducted at scales greater than traditional
    projects,

-   Information should be incorporated from other National Programs that
    were perceived to not use systems approaches, and

-   Research results should be transferred by the researchers to
    clients, partners, and stakeholders to ensure relevant progress.

The resulting NP-207 Action Plan from the workshop input did not provide
a specific research project outline, as found with the other ARS
National Programs, but gave a few examples of systems research projects.
In retrospect, this was a significant short-coming of the program
planning process. However, structure was provided by way of recognized
research components that have been regularly presented in the NP-207
Annual Reports. These have included: Cropping Systems, Integrated
Crop-Livestock Systems, Site Specific Management and Precision
Agriculture, and Decision Support Systems. The final organization of
this Accomplishment Report is arranged around general classes to which
the accomplishments are categorized based loosely on specific USDA
Strategic Goals. Supporting the accomplishment statement was a listing
of refereed publications accepted since 2002, and listings of
proceedings papers, technical notes, and extension bulletins, reports in
the popular press, or other notable records of the research.

# Research Goal I. Enhanced Capacity to Solve Problems Using System Research Approaches. 

Accomplishments were provided by 23 research projects classified as
NP-207. The total annual budget for these projects is approximately
\$28.7-million. There are approximately 60.5 Scientist Years assigned to
NP-207 projects. More than 115 accomplishments were compiled and
analyzed for this accomplishment report. The research activities were
reported for the five-year period 2002-2006 (less than 60 months because
of the accelerated review cycle to coincide the next five-year review
with NP-205, Rangeland, Pasture, and Forages), and represent a broad
range of activities over a wide geographical area (Table 1).

[Table 1. List of 24 contributing locations to the NP-207 Accomplishment
Report]{.underline}.

Ames, IA Mandan, ND\*

Auburn, AL\* Madison, WI

Beaver, WV Mississippi State, MS

Beltsville, MD Morris, MN

Booneville, AR Orono, ME

Brookings, SD Prosser, WA

Columbia, MO Pullman, WA

Corvallis, OR Salinas, CA

Dawson, GA Stoneville, MS

Florence, SC\* Sidney, MT

Fort Collins, CO Watkinsville, GA

Lane, OK\* Weslaco, TX \* not NP-207

[]{#__RefHeading___Toc147540270 .anchor}**A. Problem Area. Systems
Research Attributes Assessment**. This portion of the report is based on
the Systems Research Attributes template that was used to evaluate each
accomplishment provided by the field. The attributes were based on the
research criteria that were given by the customers at the NP-207
Workshop. The results for all accomplishments are given in Appendix 1.

[]{#__RefHeading___Toc147540271 .anchor}**1. Customer Involvement.**
Stakeholders have provided great amounts of guidance for the research
conducted to achieve the accomplishments reported by NP-207. More than
81% of all accomplishments indicated that customers were involved with
the initial problem assessment, and approximately 80% of all
accomplishments reported an ongoing involvement with customers and
stakeholders. These large percentages demonstrate the commitment of
NP-207 scientists towards this value that was identified by customers at
the first National Program Workshop. Customer involvement helps to
ensure that NP-207 research is appropriately targeted toward problems
that will benefit customers and stakeholders.

[]{#__RefHeading___Toc147540272 .anchor}**2. Research Approach.** Even
though NP-207 was formally first recognized as a National Program in
2002, a systems approach to research projects was already underway at
many of the locations involved in this National Program. A majority of
accomplishments (54%) reported their projects were based on maturing
research studies between 5-10 years old (Figure 2). Shorter-term
experiments or new systems projects that were begun less than five years
ago contributed to 29% of the accomplishments reported.
Seventeen-percent of the projects had been underway for more than 10
years.

![](media/image1.wmf){width="3.082638888888889in"
height="2.6118055555555557in"}

Figure 1. Percentage of NP-207 accomplishments that were found from
research on short-term (0-4 years), maturing (5-10 years), and long-term
(\>10 years) studies.

Small plot research contributed to the largest percentage of research
accomplishments (60%), with full-scale commercial equipment being used
for 57% of the research activities. Large landscape or field-scale
research was also a significant contributor to the accomplishments,
being responsible for 25% of the findings. Also, most accomplishments
reported contributions from on-farm experiments (60%). Multiple-location
experiments were conducted for more than 71% of all accomplishments
(Fig. 3). Most accomplishments utilized less than 20 research sites, but
a few used large numbers of sites, with as many as 80 and 150 different
sites.

The research teams that conducted the research and reported the
accomplishments were achieved mostly with multidisciplinary teams of
scientists and cooperators (88%) that often included non-ARS members
(82%). More than 46% of the accomplishments had team members from
multiple ARS locations. A large majority (84%) of the accomplishments
had multiple experimental factors in their project descriptions.

[]{#__RefHeading___Toc147540273 .anchor}**3. Measured Assessments.**
These metrics address multiple dimensions of the agricultural issues,
farm and natural resources impacted, and the context of the research.

Most research accomplished under NP-207 reported that their emphasis was
on improving production practices (83%), as opposed to improving product
quality (39%). Additionally, the majority of accomplishments were
categorized as having economic (77%) or environmental (50%)
implications, as opposed to having social impact (15%). The three most
prominent natural resources concerns addressed by NP-207 research were
soil (77%), water (68%), and plant (55%), with air quality (17%) and
wildlife (9%) addressed to a lesser extent (Fig. 4).

![](media/image2.wmf){width="3.1666666666666665in"
height="3.0541666666666667in"}

Figure 2. Histogram of the number of research sites used for each
accomplishment reported.

![](media/image3.wmf){width="3.2270833333333333in"
height="4.000694444444444in"}

Figure 3. Percentage of accomplishments that was associated with a
specific natural resource. Broad natural resources categories are based
on the USDA-NRCS Conservation Planning and Physical Effects framework
(SWAPA+H).

![](media/image4.wmf){width="2.5527777777777776in"
height="3.560416666666667in"}

Figure 4. Percentage of accomplishments that was associated with
USDA-ARS areas of mission relevance.

When asked to assess the USDA-ARS mission area relevance (Fig. 5), most
scientists chose natural resources enhanced (78%). Economic
opportunities (42%) and food quality, availability and safety (32%) were
the next two selections. Enhanced competition (16%) and nutrition (8%)
were the least associated areas of mission relevance for the NP-207
accomplishments.

![](media/image5.wmf){width="2.9993055555555554in" height="2.93125in"}

Figure 5. Number of accomplishments that identified other associated
National Programs as being relevent to the NP-207 research. A listing of
National Program numbers can be found on the Web at:
http://www.ars.usda.gov/main/main.htm

Only 19% of the accomplishments reported that NP-207 was the only
National Program to which researchers belonged. The other 81% chose at
least one additional National Program as being germane. ARS National
Programs 201 and 202 (also in Natural Resources and Sustainable
Agricultural Systems) were the two most common programs that were
mentioned as being relevant to the NP-207 accomplishments (Fig. 6), with
numerous others being mentioned less frequently.

![](media/image6.wmf){width="3.2993055555555557in"
height="4.090277777777778in"}

Figure 6. Total number of publications and technology transfer
activities reported by the NP-207 accomplishments.

[]{#__RefHeading___Toc147540274 .anchor}**B. Problem Area. Research
Impact Assessment***.* This portion of the report is based on the
Systems Research Impact template that was used to evaluate each
accomplishment provided by the field. The metrics used to assess impact
represent a wide range of features that include technology transfer,
acreage and finances affected, and influence on policies. The results of
all accomplishments are given in Appendix 2.

[]{#__RefHeading___Toc147540275 .anchor}**1. Technology Transfer.** The
scientists within NP-207 published a total of 493 refereed journal
publications and 203 extension publications (Fig. 6). This is an average
of 2.2 journal publications and 0.9 extension publications per
accomplishment. A total of 381 popular press articles were written about
the NP-207 accomplishments, or almost 1.7 articles per accomplishment.
Four patents resulted from technology developed by this national
program. A significant amount of effort was dedicated to communicating
research results directly to stakeholders through 555 field tours, 853
meeting presentations, and 81 trade show exhibits. A great amount of
cooperation with private industry was also found with 32 cooperative
research and development agreements, 81 technology and materials
transfer agreements, and varieties released. The Internet was also used
as a vehicle to communicate results to stakeholders, with 54 web sites
being updated on a regular basis with new research information.

![](media/image7.wmf){width="3.7472222222222222in"
height="3.7215277777777778in"}

Figure 7. Histogram of the acreages impacted by NP-207 accomplishments.

[]{#__RefHeading___Toc147540276 .anchor}**2. Impact of research on farm
income.** Almost four-million acres of farmland were reported to be
impacted by research from this National Program with results being
readily adopted. These enterprises range from small farms involving
organic production to large acreages where significant portions of
regions have modified their production system (Fig. 8). Benefits to
stakeholders vary from reduced impediments and expenses to increased
amounts of revenue. Examples of impediments mitigated were reduced soil
loss to erosion, reduced soil borne disease, reduced weed seed
production, reduced need for pesticides, reduced nitrogen and
phosphorous loss, reduced fuel use for tillage and grain drying, reduced
labor costs, and increased carbon storage in the soil.

Most accomplishments resulted in decreased producer expenses that ranged
from as small as \$4 per acre for improved cotton field scouting
methods, to as much as \$675 per acre for use of alternative management
practices that replaced methyl bromide use. Improved revenues ranged
from \$3 per acre for alternative methods of terminating cover crops, to
\$10,000 per acre for adoption of high-value specialty crop production.
Using researcher estimates for accomplishments that have been currently
adopted suggest that NP-207 research has increased income to American
producers \$56-162 million per year. These rough estimates do not
include future production costs savings or increased revenues from the
impact of accomplishments that are just beginning to be adopted.

[]{#__RefHeading___Toc147540277 .anchor}**3. Quality of Research
Outcome.** Stakeholder satisfaction was positive, with 63% of all
accomplishments reporting that producers' initial concerns about a
problem had been met. To a lesser degree (36%), the general public was
also deemed satisfied by the accomplishment outcome. Only 13% of all
accomplishment results were used to demonstrate some form of regulatory
compliance. Worker satisfaction was largely not addressed by this
national program, with less than 2% reporting this as an issue.

[]{#__RefHeading___Toc147540278 .anchor}**4. Impact on Policies or
Competitiveness in the Market.** A notable weakness is the lack of
accomplishment results being passed on to USDA-NRCS in support of USDA
Farm Bill Conservation Title, with only 13% reporting their research
results help customers increase access to these programs. However, this
program has great potential for impacting future Farm Bill Programs
through expanded relationships with USDA-NRCS and USDA-FSA.

Some accomplishments (18%) reported that their results had been used to
change current local, state or national policies. The competitiveness of
local customers participating in U.S. agriculture was reported to be
improved by NP-207 accomplishments, with more than half (52%) reporting
that unique products, processes, systems, or services had been produced.
The amount of agricultural product made available was increased by 29%
of the accomplishments, and the local community economy was positively
impacted by 24% of the accomplishments.

# Research Goal II. Enhanced Economic Opportunities for Agricultural Producers and Rural Communities. 

## Problem Area A. Strategies to Reduce Production Costs and Increase Profit.

[]{#__RefHeading___Toc147540281 .anchor}**1. Conservation Tillage**.
Conservation tillage has several attributes that can reduce the risk
associated with agricultural production. For example, conservation
tillage can increase crop productivity through reduced soil loss, and
increased organic matter and soil moisture. Conservation tillage can
also reduce production costs, thus increasing profitability. The
combination of increased productivity and reduced costs can further
increase profitability and reduce economic risk. In a few cases, these
accomplishments could have been listed under other problem areas, but in
these cases conservation tillage was a key to success. Researchers have
also been successful in extending this technology to their stakeholders.

[]{#__RefHeading___Toc147540282 .anchor}**Expansion of conservation
systems research project leads to technology transfer initiatives.** As
a result of a customer focus group meeting in 1999, rapid expansion of
the Conservation Systems Research Project has led to increased research
and technology transfer activities throughout the Southeastern U.S. Five
new multi-disciplinary scientists (agricultural engineer, agricultural
economist, agronomist, soil scientist, and weed scientist) and
supporting technicians were hired to conduct research that seeks to
increase adoption of conservation tillage systems throughout the region.
Additionally, specific cooperative agreements with other institutions
have resulted in new research and technology transfer thrusts that focus
on increased use of soil testing, site-specific agriculture programming,
small farmer conservation tillage assistance, and the long-term use of
reduced tillage and poultry waste as a nitrogen source in conservation
tillage systems. Results of this project have currently been seen with
the percent adoption of conservation tillage systems increasing rapidly
in Alabama, with 48% of the cropland being managed with conservation
tillage systems. This number has increased dramatically since 1990 when
the adoption rate was 15%, and has now surpassed the 41% national and
28% regional averages. **ARS Locations and Cooperators:** Auburn,
Watkinsville, Alabama Farmers Federation, Alabama Cooperative Extension
Service, NRCS. Auburn University, Alabama A&M University, Tuskegee
University. **Selected Refereed Publications:** none

[]{#__RefHeading___Toc147540283 .anchor}**Effect of landscape position
on crop yield when transitioning from conventional to conservation
tillage systems.** Many producers who are using conventional tillage
systems mistakenly think that they must suffer several years of reduced
crop yields prior to their soils responding positively to a reduced
tillage system. The first phase of a large 20-acre long-term field
experiment was completed to determine the impacts of transitioning from
a conventional tillage to a conservation tillage system. This experiment
was the first in the region to examine interactions among crop
management systems, productivity, and landscape position using soil
survey, topography, and electrical conductivity maps to define
management zones. Results indicated that in every field management zone
(including knolls, severely eroded side-slopes, and valleys) the use of
conservation systems resulted in immediate increased crop productivity
(14% on average for cotton), as compared to the conventional tillage
systems. The results of this experiment indicate that producers who farm
Coastal Plain soils can immediately begin to take advantage of increased
yields when converting their row-crop production system from
conventional tillage to conservation tillage. **ARS Locations and
Cooperators:** Auburn, Watkinsville, Alabama Cooperative Extension
Service, NRCS, Auburn University. **Selected Refereed Publications:**
Balkcom et al 2005. Terra et al., 2004. Terra et al., 2005a. Terra et
al., 2005b.

[]{#__RefHeading___Toc147540284 .anchor}**No-tillage allows more
intensive and flexible dryland cropping systems and improves soil
quality.** Dryland cropping systems on the Central Great Plains are
subject to frequent and cyclic drought spells. Even during periods of
normal precipitation, available soil moisture is marginally adequate for
most crop production that has wheat-fallow as the established crop
rotation. A long-term cooperative research project has focused on
investigating no-tillage as a way to conserve soil moisture and grow
more intensive crop rotations, such as wheat-corn-fallow,
wheat-corn-millet-fallow, or wheat-corn-sunflower-fallow. This research
has established that no-tillage conserves more soil moisture and allows
more intensive and flexible cropping choices. It also improves soil
organic matter in the surface layer that helps enhance rainfall
infiltration. These and similar research results from the ARS Central
Great Plains Experiment Station, have convinced the farmers to convert
more than half a million acres of wheat-fallow to more intensive
cropping systems, and this conversion is still increasing. **ARS
Locations and Cooperators:** Fort Collins and Colorado State University.
**Selected Refereed Publications:** Campbell et al., 2005. Sherrod et
al., 2005. Shaver et al., 2003. Sherrod et al., 2003. Shaver et al.,
2002.

[]{#__RefHeading___Toc147540285 .anchor}**Conservation practices improve
soil, air, & water quality and increase profits in perennial grass seed
production systems.** Due to a growing concern for environmental
protection of air, soil, and water and a need to improve farm profits,
ARS scientists recognized the need to research ways to improve grass
seed production systems for the 660,000 acres produced in the Pacific
Northwest. Several on-farm multi-year studies, some 10 years in
duration, and at several locations, were established using large plots,
and in some cases adjacent riparian buffers. Facilitation of research
and technology transfer goals was enhanced by active participation of
local stakeholders (farmers and environmental groups) and State and
Federal scientists and extension representing multiple disciplines.
These multi-factorial experiments demonstrated that perennial grass seed
crops could be economically produced without burning post-harvest straw
and by using no-till seeding in combination with straw chop after
harvest. Compared to conventional tillage establishment with straw
removed by baling, the ARS conservation system reduced soil erosion
40-77%, nitrate leaching 50%, establishment costs \$27-162 per acre, can
increase seed yields, allow earlier spring planting times, and increase
recreation time for farmers. Growers are experimenting with how to best
use these new practices on 15,000 acres in Oregon and Washington, and
the USDA-NRCS has adopted no-till seeding and full straw management as
practices to help grass seed farmers qualify for USDA Farm Bill
conservation program payments for the first time. **ARS Locations and
Cooperators:** Corvallis, Oregon State University, USDA-NRCS, and
US-EPA. **Selected Refereed Publications:** Field et al., 2003.
Wigington, Jr. et al., 2003. Butler et al., 2004. Gislum and Griffith et
al., 2004. Steiner et al., 2006.

[]{#__RefHeading___Toc147540286 .anchor}**Reduced tillage in potato
production systems.** Reducing production costs through the use of
conservation tillage and reduced inputs is a means of increasing the
environmental and economic sustainability of Pacific Northwest potato
production systems. Adopting conservation tillage to reduce erosion,
increase N use efficiency, and build organic matter would improve soil
and environmental quality under irrigated production systems. The major
focus of this research is to evaluate the processes controlling soil
biological activity and community structure of the soil micro-flora,
understand the mechanisms controlling weed dynamics and evaluate carbon
and nitrogen cycling, as well as, trace gas fluxes under reduced tillage
in irrigated potato production systems. This study is in its third year
under center pivot irrigation. A reduced tillage strategy was developed
that uses equipment currently available to growers and has shown potato
tuber yields under reduced tillage equaled that of conventional tuber
yields. This strategy reduces the total number of passes across the
field from nine to six, and soil disturbance operations from seven to
four (including harvest), compared to those using conventional tillage.
For sweet corn in rotation, field operations were reduced 50%.
Preliminary findings suggest that growers adopting reduced tillage in
potato production systems can reduce production costs through savings in
fuel, labor, and equipment wear. **ARS Locations and Cooperators:**
Prosser, Washington State University, Oregon State University, and
AgriNorthwest Corporation. **Selected Refereed Publications:** none

[]{#__RefHeading___Toc147540287 .anchor}**Developing a strip tillage
system for small seeded crops*.*** The high prices of fuel and
fertilizers have growers looking for new ways to maintain or improve
sugarbeet productivity, while reducing operating costs. Strip tillage
used to save fuel and reduce soil erosion, has not previously worked
well for small-seeded crops like sugarbeets because of poor soil-to-seed
contact. A special strip till implement was designed and built as part
of a conservation tillage system that also includes modified weed and
pest control, fertilization, irrigation management, and harvesting
techniques. A four-year study was initiated in autumn 2003 to compare
conventional grower practices with flat-planted, sprinkler-irrigated
sugarbeets grown after spring grains. Substantial savings in fuel were
obtained as tillage and fertilization are done in one equipment pass
with the strip tiller, compared to up to seven passes under conventional
tillage. In 2004, there were no significant differences in yields or
sugar production between the two sets of treatments; however, in 2005
the strip tilled plots produced about 17% greater yields, primarily due
to spring wind erosion protection provided by the standing straw
stubble. In contrast, the conventionally tilled plots were severely
damaged. Percentage beet sucrose was also higher in the strip tilled
plots. After only two research seasons, one grower has purchased the
specialized equipment and strip tilled more than 1,000 acres for the
2006 growing season. The local sugar company is recommending the system
to its growers, and as much as 9,600 out of about 50,000 acres in
production, based on this research. **ARS Locations and Cooperators:**
Sidney, Montana State University, Sidney Sugars, and Schlagel
Manufacturing. **Selected Refereed Publications:** none

[]{#__RefHeading___Toc147540288 .anchor}**Conservation tillage and cover
crop benefits for cotton and soybeans.** Significant interest was
expressed by customers and stakeholders to find ways to reduce
production inputs without major reductions to yield, and simultaneously
minimize the environmental impact to the surrounding area. Systems
studies were conducted to investigate the effects of reducing inputs
using conservation management practices, and develop more efficient
methods of applying agrochemicals in cotton production. The studies
compared traditional tillage-intensive methods of cotton production to
conservation methods using varying degrees of reduced tillage and
incorporation of a cover crop. Significant yield increases were observed
in cotton grown in the alternate-year rotation with corn, compared to
the continuous cotton. Results indicate significant reduction in the
tillage input can be achieved with minimal change in cotton yield.
Moreover, no-till cotton production can be more profitable than
conventional production methods. The change from conventional production
to conservation tillage production practices requires varying degrees of
equipment change. Therefore, the environmental and economic factors will
need to be considered carefully on a case-by-case basis before making
these changes. This study, conducted as part of the Mississippi Delta
Management Systems Evaluation Area project evaluating sensor-controlled
hooded sprayers, also resulted in 75% reduction in herbicide usage
compared to typical chemical weed control methods in conservation
tillage systems. **ARS Locations and Cooperators:** Stoneville, U.S.
Geological Survey, Delta Research and Extension Center, MSU, Mississippi
Department of Environmental Quality, Mississippi Soil and Water
Conservation Commission, Mississippi Farm Bureau Federation. **Selected
Refereed Publications:** Bryson et al., 2004. Hanks et al., 2004. Hanks
et al., 2001. Bryson et al., 2001. Wesley et al., 2001.

[]{#__RefHeading___Toc147540289 .anchor}**Systems approach improves
adoption of conservation tillage systems in the Southeastern U.S.A.**
Identifying multiple benefits of conservation tillage systems at the
farm scale can help increase adoption. Researchers from ARS locations
conducted multidiscipline on-farm research to improve conservation
tillage systems for cotton. An approach was developed to ensure
interaction among scientists and producers in identifying critical
issues important to producers. Adding cover crops to the production
systems increased yields and lowered insecticide use, resulting in
overall more profitable cotton production, compared to conventional
cotton without a cover crop. There was little difference in the effect
of cover crop systems on soil microarthropod communities. Strip-tillage
with in-row sub soiling increased cotton yield over strict no-till in
these sandy coastal plain soils, and winter rye consistently produced
great amounts of biomass and soil cover. However, N availability
following rye was decreased, compared to some other cover crops,
indicating that N applications need to be increased. Research results
were provided to over 2,000 Southeast producers by establishing field
demonstration plots and participating in field days. This is a maturing
systems accomplishment with a few publications and additional outreach
activities still in the works. **ARS Locations and Cooperators**:
Watkinsville, Tifton, Dawson, Auburn University, NRCS, University of
Georgia, US-EPA. **Selected Refereed Publications:** Schomberg et al.,
2006. Schomberg et al., 2003. Tillman et al., 2004.

[]{#__RefHeading___Toc147540290 .anchor}**Increasing Adoption of
Conservation Tillage Technology in the Tennessee Valley Region:** Soil
erosion and compaction, and weed pressure are management concerns to
growers in the Tennessee Valley. Soil erosion from continuous cotton
cropping and governmental regulations caused cotton producers in the
Tennessee River Valley of northern Alabama to try no-tillage in the
early 1990s, but yield reductions prevented widespread adoption of this
system. Research developed a conservation cropping system for the
Tennessee Valley region that included non-inversion fall tillage, and
has been expanded to include improved nitrogen management and irrigation
efficiency, and development of tillage systems to maximize water
infiltration and reduce erosion. The research results were rapidly
transferred via popular press articles to growers, consultants,
extension agents, and NRCS staff, resulting in adoption rates of
conservation tillage exceeding 70 to 80% in the largest cotton producing
counties in the region (over 120,000 acres of conservation tillage
cotton). When this research was started in the mid-1990s, only 30-40% of
producers in this region were using conservation tillage technology.
**ARS Locations and Cooperators**: Auburn, Auburn University, and
USDA-NRCS. **Selected Refereed Publications:**

[]{#__RefHeading___Toc147540291 .anchor}**Conservation tillage systems
for hot and dry climates**. Excessive cultivation and high winds in the
Rio Grande Valley of Texas have resulted in appalling rates of soil
erosion and losses of soil organic matter, which declined from 4% at the
time of settlement, to as low as 0.3% today. To counter these losses and
improve soil productivity, a tillage system was developed that conserves
soil and soil organic matter through reduced tillage and conservation
residue management on cotton, corn, and sorghum fields. Sweet corn and
broccoli also benefited from adoption of the conservation tillage
practices. When adopted, these systems doubled organic matter in
nine-years and wind erosion was prevented. Soils with 60% crop residue
cover accumulated soil blown from nearby fields. Cotton and corn residue
management was aided by the finding that plant polyphenols contribute to
organic C retention when residues are managed correctly. Weed control
through a modified ridge tillage system was critical. Soil nutrient
distribution became stratified, enriching the surface 10 cm of soil with
P, N and C. Coupling new soil management tools to new cropping
strategies, such as including legumes in rotation, presented challenges
regarding nodulation of the legume that continue to be investigated.
Conventional, organic, and transitional growers are using these results,
since they are scale-free and support sound soil management in many
cropping systems. Farmers have readily adopted these practices because
production costs are lower. The NRCS Energy Consumption Awareness Tool
calculates, based on growing cotton, corn, and grain sorghum, fuel
savings of \$17.25 per acre compared to conventional practices. These
integrated systems have been adopted on more than 350,000 acres in just
the four-county lower Rio Grande Valley area of south Texas. **ARS
Locations and Cooperators:** Weslaco, Texas A&M University extension.
**Selected Refereed Publications:** Chaoui et al., 2003. Materon et al.,
2001. Materon et al., 2003. Zibilske et al., 2003. Zibilske et al.,
2005.

[]{#__RefHeading___Toc147540292 .anchor}**2. Rotation Crop Sequences**.
Rotation crops can provide a wide range of benefits. The interest in
rotation crops is fueled by several factors: increasing input cost,
environmental concerns, increased responsiveness to changing market
conditions, pest control, and risk management. The research
accomplishments demonstrate how the use of rotation crops can reduce the
environmental impacts of agriculture such as lower use of toxic
chemicals and runoff. They also show that the use of rotation crops
leads to integrated systems that are more robust under a wide variety of
physical and economic conditions. Furthermore, several studies show that
the use of rotation crops can improve farm profitability and reduce
economic risk.

[]{#__RefHeading___Toc147540293 .anchor}**Diversifying crop rotations
and reducing tillage can reduce risk to Northern Corn Belt farmers.**
Despite national trends toward adoption of conservation tillage, farmers
in the Northern Corn Belt continue to use intensive tillage. In
addition, there has been a reduction in crop diversity in this area.
Farmers need assurances that using new production practices will not put
them at further risk of financial loss. The research showed that ridge
tillage increased profitability, reduced fuel and labor use, and reduced
economic risk, relative to conventional tillage for a corn and soybean
rotation. The research also showed instead of continuous corn
production, corn rotations including soybean, spring wheat, and alfalfa
were valuable risk management tools when government payments and crop
insurance are not available. However, when growers choose to use both
government programs and crop insurance, the relative benefits of crop
diversification in reducing risks are decreased. This new research is
also beginning to show that no-till and many strip tillage systems
increased profitability and reduced fuel use for a corn and soybean
rotation, compared to moldboard plow and chisel plow tillage systems.
The research is helping assure Northern Corn Belt farmers who want to
adopt more sustainable production practices that reduced tillage and
diverse crop rotations can reduce economic risks and complement other
risk management tools including government programs and crop insurance.
The research can also help policy makers find creative ways to design
programs that provide economic incentives for producers to adopt
conservation practices. **ARS Locations and Cooperators:** Morris,
Brookings. **Selected Refereed Publications:** Archer, et al 2002.

[]{#__RefHeading___Toc147540294 .anchor}**Dynamic systems approach to
rotation crop selection.** Agricultural producers in the northern Great
Plains face challenges when determining the best cropping sequence to
maximize their production, have the greatest benefits for the
environmental, and meet personal farming goals. A crop sequencing
project was done that involved a crop-by-crop residue design, where 10
crops were planted on the residues from the same crops. This combination
of 100 crop sequences allowed evaluation of the positive and negative
effects of crop sequences in similar soil and water conditions. The
project allowed evaluation of contrast effects for crop rotation
(including annual forage and cover crops), residue removal, and tillage
(minimum and no-till) on production, precipitation-use efficiency, plant
diseases, and soil quality. The project was established in 1993 and just
completed its twelfth year. The research was used to develop the
*Dynamic Cropping Systems* concept. *Dynamic Cropping Systems* is a
management philosophy emphasizing using adaptability and knowledge
transfer to achieve a producer's production, economic, and resource
conservation goals. *Dynamic Cropping Systems* has been transferred to
end-users through peer-reviewed journal articles and a symposium
involving Great Plains cropping systems researchers from Texas to
Canada. An easy to use CD version of *The Crop Sequence Calculator* was
developed that allows producers to evaluate the advantages and
disadvantages of the different crop sequences based on information about
production economics, soil water use, surface soil properties, plant
diseases, weeds and insects. Over 12,000 copies of the CD have been
distributed to producers, extension agents, consultants, and university
educators, and been featured in popular press articles and as an exhibit
in the congressional briefing. **ARS Locations and Cooperators:**
Mandan. **Refereed Publications:** Krupinsky et al., 2006. Liebig et
al., 2006. Merrill et al., 2004.

[]{#__RefHeading___Toc147540295 .anchor}**3. Cover Crops, Crop Residues,
and Manure Use.** Innovative cropping systems that make use of
non-purchased inputs (e.g., manure) and integrate biological components
(e.g., cover crops, residue management) may allow producers to reduce
the cost of purchased inputs. Research activities are underway to
investigate important components of such systems, and to develop and
test integrated cropping systems that include these components.

[]{#__RefHeading___Toc147540296 .anchor}**Cover crop-based production
system may be a potential alternative to methyl bromide.** Agriculture
in the southeastern U.S. has been negatively impacted by the North
America Free Trade Agreement (NAFTA), which opened the borders and
eliminated tariffs on free trade with Mexico. Also, the Montreal
Protocol banned the manufacture, sale, and use of methyl bromide in the
U.S., but extended its use in Mexico and other developing countries.
These two policies have flooded U.S. markets with imported vegetables,
leaving the U.S. growers less competitive. Research was conducted to
evaluate the feasibility of using a biologically-based system for winter
production of fresh-market tomatoes. The system consisted of a crop
rotation in which nematode-resistant cover crops (cowpea, velvetbean, or
sun hemp) were followed by a nematode and *Fusarium*-*Verticillium*
resistant tomato cultivar. In selected years, tomatoes grown in the
cover crop-based systems produced equivalent or higher yields, and had
net returns equivalent to the conventional methyl bromide fumigation
system. Additional research is needed to define the viability of this
system across a wider range of nematode, disease, and soil conditions.
These results show methyl bromide is not necessary under all conditions,
and that use of a cover crop may be an economically viable alternative
for growers of high-value crops in the southeastern U.S. In addition,
the alternative system reduced soil erosion, improved soil fertility,
and has great potential for protecting the environmentally fragile
agro-ecosystem of the Everglades. **ARS Locations and Cooperators:**
Beltsville, University of Florida. **Selected Refereed Publications:**
Abdul-Baki et al., 2004a. Abdul-Baki et al., 2002. Wang et al., 2002.
Abdul-Baki et al., 2004b. Roberts et al., 2005.

[]{#__RefHeading___Toc147540297 .anchor}**Utilizing fall-planted cover
crops for weed suppression in potato production systems.** Weeds in
potato can reduce tuber yield up to 50%, reduce tuber size and specific
gravity, reduce harvest efficiency, and harbor nematodes and pathogens.
Greater than 90% of the potato acreage in the U.S. is treated with at
least one herbicide to control weeds. It was demonstrated that
autumn-planted cover crops of oat/vetch, mustard, and winter wheat can
reduce the weed incidence in potato as well as reduce soil erosion,
reclaim leachable nitrogen, increase water infiltration rates, and
suppress nematode and potato pathogens ­­- thereby lowering fumigant
rates. Growers have rapidly adopted use of autumn-planted mustard cover
crops on over 20,000 acres annually in Washington State. **ARS Locations
& Cooperators**: Prosser. **Selected Refereed Publications**: Collins et
al., 2005. 

[]{#__RefHeading___Toc147540298 .anchor}**Cover crops enhance date
production.** Date production is localized in the Coachella Valley in
southeastern California and generates about \$38-million annually. Due
to a number of stresses including high soil compaction, low fertility,
and lack of organic matter in sandy soils, date yield and fruit quality
have been declining. A two-step solution was developed consisting of
deep slip plowing between the tree rows to break the hard pan and allow
the movement of water and nutrients deeper into the soil profile, and a
management system using a native Lana vetch to cover the soil surface
from October to May. The cover crop suppressed weeds, improved soil
fertility, recycled macro- and micro-nutrients, improved water
percolation, shaded the soil surface, reduced evaporation, and lowered
soil temperature in this excessively hot region. Within three years
after implementing, tree growth tripled, yields increased by an average
of 12-20%, and fruit quality was improved. At the same time, production
costs were reduced by \$100 per acre due to savings on cultivation,
fertilizer, and irrigation. Approximately 45% of the date orchards in
Coachella Valley are presently applying the cover cropping system. In
addition, this technology has been extended to other crops resulting in
an increase of cover cropping acreage from 500 to 25,000 acres in the
Coachella Valley, including use on approximately 40% of the grape
acreage. **ARS Locations & Cooperators**: Beltsville and USDA-NRCS.
**Selected Refereed Publications:** Abdul-Baki et al., 2002.

[]{#__RefHeading___Toc147540299 .anchor}**Evaluation of novel cover
crops.** Many farmers rely on a few cover crop species, varieties, and
mixtures; thus are particularly vulnerable to cover crop failure in case
of disease or pest outbreak. Several rye breeding lines from the
University of Florida were evaluated for use as winter cover crops, and
novel cover crop mixtures of legumes, cereals, and mustards were used.
This research identified several promising novel cover crop mixtures,
and a rye breeding line that was well adapted to the Salinas Valley,
California, vegetable production area. Collaboration with a local seed
company resulted in the release of a new rye variety for commercial use.
This research played an important role in the increased adoption of
cover cropping by farms in the region. Farmers have used new rust
resistant rye variety and novel cover crop mixtures on more than 2000
acres of land, a significant land area in this high-value fresh market
vegetable production region. **ARS Locations & Cooperators**: Salinas,
University of Florida, L.A. Hearne Company. **Selected Refereed
Publications**: none.

[]{#__RefHeading___Toc147540300 .anchor}**Cover crop roller technology
may be a key component of conservation systems.** Cover crops have been
shown to provide beneficial results for crop production and
environmental protection. However, cover crops can interfere with cash
crop establishment and growth. Roller crimper technology may provide a
valuable alternative to chemicals for killing cover crops, with the
added incentive of providing a flat, unidirectional mat of residue cover
for planting into. A custom-designed roller effectively and economically
killed cover crops in conservation tillage systems. In addition,
alternate designs that reduce the vibration associated with rolling
cover crops allow tractor drivers to traverse the field at typical
speeds. One of the designs has resulted in a U.S. Patent. This
information is being used by producers and manufacturers to create
better implements that enhance the use of conservation systems for
row-crop production. The technology is now being considered by other ARS
researchers who use cover crops in their studies. **ARS Locations and
Cooperators:** Auburn**,** Watkinsville**,** Alabama Cooperative
Extension Service, NRCS State and National, Auburn University.
**Selected Refereed Publications:** Ashford et al., 2003. Raper et al.,
2005. Raper et al., 2004.

[]{#__RefHeading___Toc147540301 .anchor}**Discovering the molecular
mechanisms that cover crops influence in production systems.** Legume
cover crops mulches were shown to influence many aspects of cropping
systems including enhancing crop production and inhibiting weed and pest
populations. A network of scientists from diverse disciplines was
assembled to study process level interactions of cover crops within
agro-ecosystems. Molecular approaches demonstrated that expression of
select genes and proteins is enhanced during delayed crop senescence and
increased disease tolerance in hairy vetch grown tomato plants. The team
has the capacity to extend our understanding of mechanisms by which
cover crops influence agro-ecosystems that could lead to more precise
management practices for enhancing cover crop use. **ARS Locations &
Cooperators**: Beltsville, Fargo, Ithaca, Cornell University, Boyce
Thompson Institute, Purdue University, University of Maryland, Salisbury
and College Park. **Selected Refereed Publications**: Kumar et al.,
2004a. Kumar et al., 2004b. Kumar et al., 2005. Mills et al., 2002.
Teasdale et al., 2004. Rice et al., 2005.

[]{#__RefHeading___Toc147540302 .anchor}**Residue management attachment
developed for no-till drills.** Conservation farming systems are
problematic when excessive and poorly distributed surface residue causes
poor no-till drill performance, uneven seedling emergence, slow plant
growth, and depressed crop yields. To overcome this problem, a drill
attachment was developed to manage crop residue next to the furrow
openers of hoe-type no-till drills, improving seedling establishment by
over 17% and crop yield by up to 12% in conservation farming systems.
The patented residue management wheel is commercially viable because of
its adaptability to a number of popular drill-opener geometries.
Equipment manufacturers and researchers in Oregon, Washington, Canada,
and Australia are experimenting with how to best use the residue
management wheel on several thousand acres. In addition to improving
system profitability, the ability to seed into high residue levels will
eliminate the need for field burning, thus improving air- and
soil-quality and reducing greenhouse gas emissions. **ARS Locations &
Cooperators**: Pendleton and researchers in Canada and Australia.
**Selected Refereed Publications:** Siemens et al., 2002. Siemens et
al., 2004. Siemens and Wilkins, 2006. Wilkins et al., 2002.

[]{#__RefHeading___Toc147540303 .anchor}**4. Integrated Practices to
Minimize Pest Impacts.** Populations of agricultural pests are a part of
the natural agricultural ecosystem. Pest control has often been viewed
as an isolated production practice. However, more is being done to
incorporate other production activities as factors that may moderate
pest populations to reduce the amounts of pesticides to sustain
agricultural productivity. In some cases, pesticide use may be
eliminated.

[]{#__RefHeading___Toc147540304 .anchor}**Regional efforts to reduce
weed pressures in the Pacific Northwest**. A coordinated weed and
integrated systems research has just been created to address weed
management issues in Pacific Northwest cropping systems; to develop
improved precision nitrogen placement methods that use information from
crop yield monitors and grain protein sensors; and investigate the soil,
landscape, and climate factors that influence crop nitrogen demand,
nitrogen use, and nitrogen loss across dryland landscapes. Solving
production problems involving highly competitive weeds in wheat
production systems, as well as the impacts of agriculture on water
quality in the Pacific Northwest region are critical issues that must be
solved to maintain a viable economic agriculture base. This
multidisciplinary integration and linkage addresses a broad range of
agro-climatic conditions, extends resources by avoiding research
duplication, accelerates the delivery of new developments, and broadens
the geographical base of stakeholder support for conservation research
in Pacific Northwest. **ARS Locations & Cooperators**: Pendleton and
Pullman. **Selected Refereed Publications**: none

[]{#__RefHeading___Toc147540305 .anchor}**Small grain cover crops reduce
the need for herbicide applications.** Cover crops may be useful for
weed control but more research is needed to discover their successful
management and benefits. Research in the mid-west demonstrated that
autumn-planted small grain cover crops reduced soil erosion, nitrate
leaching, and suppressed weeds in whole-system experiments. A single
herbicide application to winter rye at anthesis, compared to application
at the 2^nd^ node growth stage, lowered subsequent weed density in
soybean by 81%. No-tillage soybean following a rye cover crop using
mechanical control alone may be a viable management system for organic
producers. These maturing research findings are helping USDA-NRCS and
non-government organizations refine standards and educational programs
to encourage the use of cover crops to reduce production costs, decrease
nutrient and sediment contamination of surface waters, and still
maintain productivity. **ARS Locations & Cooperators**: Ames, Iowa State
University, USDA-NRCS. **Selected Refereed Publications**: Westgate et
al., 2005. Singer and Kohler. 2005.

[]{#__RefHeading___Toc147540306 .anchor}**Cropping practices and
rotations reduce the negative impact of weeds in potato production
systems.** Weeds of the Solanaceae family harbor nematodes and pathogens
of potato resulting in increased nematode and disease incidence in
potatoes. Soil fumigation is used to control corky ringspot disease
(CRS) and root knot nematodes, costing \$22-million annually in
Washington State. Cropping practices have been developed that utilize
weed-free alfalfa or spearmint rotations to eliminate CRS and reduce the
need for fumigation. Likewise, scientists coupled root knot nematode
resistant potato breeding lines with improved nightshade control
practices that allows growers to grow a marketable potato crop in soils
containing root knot nematodes. Research revealed a key in both these
cropping systems was elimination of hairy nightshade and certain other
weeds. Growers can utilize these findings to cleanse CRS from problem
fields and reduce the need for soil fumigation to control nematodes.
**ARS Locations & Cooperators**: Prosser. **Selected Refereed
Publications**: Boydston et al., 2004. Hutchinson et al., 2005a.
Hutchinson et al., 2005b.

[]{#__RefHeading___Toc147540307 .anchor}**Management strategies in
rotation crops reduce populations of volunteer potato.** Volunteer
potatoes, prevalent in potato growing regions with mild winter
temperatures, are considered a weed and are difficult to manage in crop
rotations. Volunteer potatoes harbor pathogens, insects, and nematodes
of potato, resulting in increased pesticide use totaling \$6-million
annually and management costs for rotation crops exceeding \$5-million
annually in Washington State. ARS Scientists have developed management
practices for volunteer potato based on biology of the weed, cultivation
and herbicide interactions, rotation crop competitiveness, biological
control, and tillage level. Management options developed in sweet corn
eliminate 99% of new tubers produced by volunteer potato. Management
options including carrot, onion, and sweet corn prevent all yield and
quality losses caused by volunteer potato. Growers can utilize these
practices to improve yields, reduce losses from volunteer potato, and
reduce disease, insect, and nematode problems and pesticide use in the
potato crop. **ARS Locations & Cooperators**: Prosser. **Selected
Refereed Publications**: Boydston, 2004. Williams, II et al., 2004.
Boydston and Williams, II et al., 2005. Williams, II and Boydston, 2005.
Williams, II and Boydston, 2006.

[]{#__RefHeading___Toc147540308 .anchor}**Integrated management
strategies reduce jointed goatgrass in the Pacific Northwest.** Jointed
goatgrass is a winter annual grass weed introduced from Eurasia and is
genetically similar to winter wheat. Infestations in winter wheat fields
in the western United States costs growers more than \$145-million
annually. Normal production practices from area were compared to a range
of integrated practices that included a one-time residue burn, crop
rotation, use of competitive cultivars, varying seeding rates and dates,
and large seed size. Even though jointed goatgrass is not entirely
dependent on cold weather for reproduction and can produce viable seed
from spring germinating plants, competition can be reduced in integrated
management systems. At one study location, crop yield was increased 20%
and crop quality increased 50% in the integrated system, compared to the
growers' conventional system. Many of these integrated strategies have
been adopted by winter wheat producers in the western United States. The
alternative strategies reduced jointed goatgrass dockage in wheat that
met the clean-grain standards desired by Gulf Coast and Pacific Rim
countries. **ARS Locations & Cooperators**: Pullman and Washington State
University. **Selected Refereed Publications**: Walenta et al., 2002.
Young et al., 2003.

[]{#__RefHeading___Toc147540309 .anchor}**No-till spring cropping system
decreases downey brome populations.** The most prevalent wheat
production system in the Pacific Northwest is the winter wheat-fallow
system which encompasses almost 4.5 million acres. This system is
characterized by winter annual grass weeds, soil borne diseases, poor
soil quality, and is erosion-prone. For 12 years, a multi-disciplinary
team of scientists and a group of interested producers conducted a
long-term, field-scale integrated crop management research approach to
develop conservation tillage spring cropping systems. No-till spring
cereal rotations and reduced-tillage winter wheat fallow decreased downy
brome populations more than 99%, compared to conventional wheat-fallow.
In addition, conservation tillage wheat-fallow was profitable and
reduced tillage operations more than 60%, compared to conventional
wheat-fallow. A survey was conducted that documented for US-EPA that
more than 60% of the spring cropping systems field day attendees
conducted independent trials with one or more research technologies and
that 50% of these trials resulted in permanent adoptions. This research
has greatly redirected the focus of agronomic research in the Pacific
Northwest and other national semi-arid wheat production regions. **ARS
Locations & Cooperators**: Pullman, Washington State University,
University of Idaho, Oregon State University, Washington Wheat
Commission, USDA-NRCS, US-EPA. **Selected Refereed Publications**: Young
and Thorne, 2004. Thorne et al., 2003. Forte´-Gardner et al., 2004.

[]{#__RefHeading___Toc147540310 .anchor}**Development of a biointegrated
production system for strawberries eliminates the need for fumigation.**
Fumigation with methyl bromide for weed control is being phased out due
to compliance with the Montreal Protocol. An ARS led multi-disciplinary
team developed and tested variations of a biologically integrated
production system for conventional strawberries to control weed in the
absence of soil fumigation. The team integrated production system
provided weed control and showed that mycorrhizal inoculants were not
required. A CRADA was established and the research has since been
adopted in one year on 400 acres of strawberries, representing
approximately \$8,800,000 in production costs. **ARS Locations &
Cooperators**: Salinas, University of California, California Strawberry
Commission. **Selected Refereed Publication**s: Bull and Vice, 1998.

[]{#__RefHeading___Toc147540311 .anchor}**Many approaches used together
can increase New England agriculture profitability.**

There are approximately 23,000 diverse small farms in New England that
require optimal combinations of rotation crops and conservation
practices to achieve maximal individual profitability. The right
combination of practices not only brings growers additional income, it
can also be an effective way to suppress potato diseases, enhance soil
nutrient content, and boost crop productivity---all while reducing the
use of chemicals. Integrated soil, plant disease, crop productivity, and
economic research have been used to develop potato crop rotations that
increase profits. Incorporating canola into the rotation reduced
*Rhizoctonia*, common scab, and powdery scab diseases by 20-50%, thereby
increasing both potato yield and quality. Controlling the common weed
hairy nightshade reduces a source of the fungus that causes Late Blight.
Using ryegrass cover crops not only reduces soil erosion during the
winter, but also helps to reduce *Rhizoctonia*. The introduction of
raised planting beds seeded with green-sprouted potatoes consistently
increases net income \$40 per acre. **ARS Locations & Cooperators**:
Orono, Maine Potato Board, National Potato Council, University of Maine.
**Selected Refereed Publications**: Brewer and Larkin, 2005. Griffin and
Porter, 2004. Halloran, 2006. Larkin, 2002. Larkin, 2003. Larkin and
Honeycutt, 2006.

[]{#__RefHeading___Toc147540312 .anchor}**Development of a PCR protocol
for rapid detection of *Cercospora beticola*.** Cercospera Leaf Spot
(CLS) is a major disease of sugarbeets (*Beta vulgaris*) around the
world, and management options to minimize pesticide use require early
and rapid detection. All current protocols to detect disease, while
accurate, may take several days or weeks to complete, allowing for
further spread of the disease if present in the interim. To address this
problem, scientists have developed a PCR protocol for rapid detection of
*Cercospera beticola,* the causal agent of CLS; which, unlike other
molecular based protocols, can be done in less than one day and does not
require isolation, subculture or purification of the genomic DNA of the
target pathogen from symptomatic host plant tissues. PCR trials in the
lab indicated that the method discriminated the target segment of the
pathogen in the host tissue in one day, compared to several days using
other methods. This newly developed PCR protocol is a powerful new tool
for management of this pathogen in sugarbeets, and also enables a new
avenue for extensive, timely screening and identification of secondary
hosts such as weeds and other crops important in the control of the
disease. This protocol also played a crucial role in recent
identification of safflower, a major field crop in eastern MT and
western ND, as a secondary host of *C. beticola*. The potential of the
protocol was recognized by Sigma-Aldrich which is now marketing a kit
based on published information on the Sidney protocol. The nucleotide
sequence of *C. beticola* actin gene has been deposited with GenBank
(Accession \# AF443281). **ARS Locations & Cooperators**: Sidney, Fargo,
Montana State University, and New Mexico State University. **Selected
Refereed Publications**: Lartey, 2006.

[]{#__RefHeading___Toc147540313 .anchor}**Safflower is a secondary host
of *Cercospora beticola*.** Safflower (*Carthamus tinctorius* L.) is
most often grown in dryland conditions, although it may also be produced
in irrigated sugarbeet (*Beta vulgaris*) rotations and is often found in
adjacent fields. Safflower had been previously reported to be
susceptible to *Cercospora carthami,* which has never been reported to
occur in the USA. Using the novel PCR-based rapid detection strategy and
ELISA techniques, the researchers detected *C. beticola* in infected
safflower plants and proved that safflower could be a secondary host.
The infection of safflower (Family: Asteraceae) is the first known proof
of family cross infection by a *Cercospora*, and also raises the
possibility of cross infection of other crops by *Cercospora* species.
This finding is highly significant, as it raises several questions with
regard to rotation of sugar beet, safflower in particular, and viable
crop rotations in general. There is also the possibility that
*Cercospora* species that have been identified as pathogens of specific
plant families may be isolates of a species that infect other families.
Future research will verify this hypothesis. Growers, who are planning
to rotate or are in the process of rotating safflower with sugar beet or
plant the two crops adjacent to one another, are being made aware of the
potential source of infection of *C. beticola* from either crop. **ARS
Locations & Cooperators**: Sidney, Fargo, Montana State University, and
New Mexico State University. **Selected Refereed Publications**: Lartey,
et al., 2005.

[]{#__RefHeading___Toc147540314 .anchor}**Alley cropping of alfalfa
reduces need for insecticides, thus increasing profitability
potential.** Alfalfa forage commands high prices and is in high demand.
However, insect damage and the expense of frequent insecticide
applications discourage production in many regions of the United States.
The occurrence of insect-eating predatory bugs in alley cropping systems
versus conventional alfalfa production systems were studied. Alfalfa
alley cropped in 80-foot alleyways support insect populations that were
twice as diverse and contained twice as many beneficial predatory
insects than pest insects, compared to conventional monocropped alfalfa.
These results imply that less insecticide may be needed to control
alfalfa weevils in alley cropped alfalfa compared to conventional
alfalfa, thus increasing production and reducing costly inputs. **ARS
Locations & Cooperators**: Columbia and University of Missouri.
**Selected Refereed Publications**: Stamps et al., 2002.

[]{#__RefHeading___Toc147540315 .anchor}**Conservation tillage with a
rye cover crop reduces thrips populations in Southeast USA cotton.**
This research addressed issues associated with soil management, crop
management, insect pests, and crop quality. ARS scientists in South
Carolina found that early season populations of thrips, an early season
insect pest of cotton, were lower in cotton grown with conservation
tillage than in cotton grown with conventional tillage, especially when
a rye cover crop was used. This may lead to improved integrated pest
management recommendations for this cropping system. This research has
contributed to the significant increase in acres where conservation
tillage is being used for crop production in the southeast. Growers,
consultants, extension agents, and NRCS personnel are the primary
beneficiaries of this research. **ARS Locations & Cooperators**:
Florence and Clemson University. **Selected Refereed Publications**:
Bauer et al., 2004. Locke et al., 2005. Manley et al., 2003.

[]{#__RefHeading___Toc147540316 .anchor}**5. Overcoming Limited Water
Availability.** Supplemental irrigation is critical for some production
systems, and can make the difference for being profitable. Profits can
be increased through timely applications of the right amounts.
Technologies are being developed to optimize water use efficiency and
reduce the adverse impacts of irrigation on the environment. This
research is also helping to reduce conflicts between rural and urban
water users.

[]{#__RefHeading___Toc147540317 .anchor}**Optimization of crop
performance through the proper water resource management.** Increased
pressure to maximize and stabilize crop yield has led to greater use of
irrigation in the Mississippi Delta and notable depletion of the ground
water. Research was conducted on crop water use and irrigation practices
to increase the efficiency of irrigation water use in cotton cropping
systems. This nascent research is aimed at improving management of water
resources by providing suitable methods of irrigation scheduling, crop
water detection, and tillage for use by local farmers. Information from
weighing lysimeters installed in a cotton production field indicates
that the traditional crop coefficients based on days-after-planting does
not work well for humid regions. Development of more accurate crop
coefficients for the region, together with suitable weather-based and
soil-water balance models will improve irrigation scheduling
effectiveness. Remote sensing systems, in-field sensors, and visual
indicators that integrate the effects of soil type, weather, and
evapotranspiration have been shown to be useful indicators of crop water
stress and the need for irrigation. One simple scheduling tool (UGA EASY
Pan - Evaporation-based Accumulator for Sprinkler-enhanced Yield) allows
remote observation of evaporation that can be correlated with crop water
use. The UGA EASY Pan was evaluated for use in Mississippi, with a
potential 25% water savings. **ARS Locations & Cooperators:**
Stoneville, Louisiana State University, Mississippi State University,
Clemson University. **Selected Refereed Publications:** Pringle and
Martin, 2003. Thomson and Brazil, 2002.

[]{#__RefHeading___Toc147540318 .anchor}**Feedback sensor systems for
real time water management and self-propelled irrigation system decision
support.** Self-propelled center pivots and linear move irrigation
systems are particularly amenable to site-specific, variable-rate
applications. These systems also provide a platform on which to mount
sensors for real-time monitoring of plant and soil conditions that can
be supplemented with radio-linked, distributed, small
micrometeorological and soil water sensing stations scattered across a
field. A local, radio-linked ag-weather network is being developed so
on-farm research results can be extended from one location to another.
The local area weather network has now integrated with radio-linked,
distributed field sensing stations to monitor real-time conditions of
soil and plant conditions in MT and ND. A nascent decision support
program with local and field sensing systems to control the variable
rate irrigation is being developed. This research consolidates
technology development and integration of self-propelled irrigation
systems, variable-rate application controllers, distributed sensor
networks, wireless radio telemetry, and decision support systems. **ARS
Locations & Cooperators**: Sidney and Washington State University.
**Selected Refereed Publications:** Leib et al., 2003. Jabro and Evans,
2006.

[]{#__RefHeading___Toc147540319 .anchor}**Decision support systems for
irrigation scheduling in peanuts, corn, and cotton to improve profits
and adoption.** Persistent drought, urban expansion, and interstate
litigation are collectively threatening irrigation water supplies in
U.S. peanut producing regions. The National Peanut Research Laboratory
has developed *Irrigator Pro* irrigation decision software and is
involved in active technology transfer for commercial scheduling of
irrigation in peanuts, corn, and cotton to assist producers in making
improved decisions that will increase economic returns and conserve
natural resources. *Irrigator Pro* for Peanuts has documented increases
of 300 pounds per acre yield and 2% in *Sound Mature Kernels* which
equates to an increased revenue of \$60.25 per acre for growers using
this systems. Based on these results, the Georgia Soil and Water
Conservation Commission initiated an incentive program to encourage
producers to adopt and follow the recommendations of *Irrigator Pro* for
peanuts, corn, and cotton by providing payments to qualifying producers.
In Georgia during crop year 2006, there were 2,700, 10,100, and 8,400
acres of corn, cotton, and peanuts included in the incentive program. In
addition to the incentive program, adoption by producers and crop
consultants is occurring due to the demonstrated benefits of *Irrigator
Pro* for peanuts, corn, and cotton. The state supported incentives
program based on Irrigator Pro results will be used in support of USDA
Farm Bill Conservation Title Payments to interested producers. **ARS
Locations & Cooperators**: Dawson. **Selected Refereed Publications**:
Davidson et al., 2002. Zhu et al., 2004. Sorenson et al., 2004. Lamb et
al., 2005. Price et al., 2005.

[]{#__RefHeading___Toc147540320 .anchor}**Reduced supplemental
irrigation in three Southeastern conservation tillage systems.** Several
factors have increased attention on agricultural water use including an
increase in water withdrawals due to consecutive drought years, an
increase in irrigated crop acreage, and interstate litigation regarding
water rights and availability. Limits on the availability of water for
crop irrigation in the Southeast have been imposed and the future
expansion of irrigated acreage may be limited unless alternative methods
of irrigation are adopted or current practices are made more efficient.
Conservation tillage has the potential to reduce irrigation amounts and
frequency of irrigations. ARS researchers have demonstrated that
conservation tillage practices, such as strip-tillage into a rye or
wheat cover crop, produced equivalent peanut and corn yields with 33%
less supplemental irrigation in 3 of 4 years. Net return was highly
year-dependent, but only conservation systems, either strip tillage or
no-tillage, had positive net returns in each of four years in a
corn-peanut-cotton rotation. Results from this on-going field study are
being used to modify irrigation decision support systems. As a direct
result of these studies, the Georgia Soil and Water Conservation
Commission has recognized conservation tillage as an important aspect of
water conservation plans that must now be in place for the permitting of
new agricultural withdrawals. This research is helping to resolve some
of the questions about conflict between rural and urban water users.
**ARS Locations and Cooperators:** Dawson and Georgia Soil and Water
Conservation Commission. **Selected Refereed Publications:** none

[]{#__RefHeading___Toc147540321 .anchor}**Nitrogen and irrigation best
management practices for potatoes on coarse textured soils.** Potato
production in the Columbia Basin region of the Pacific Northwest is
dependent on irrigation. Soils in this region are sandy and readily
leach water and nutrients below the root-zone. Long-term research found
that capacitance probes are effective tools for real-time, continuous
monitoring of soil water content at various depths in the soil profile
for potato production in sandy soils. Irrigation schedules that
maintained optimal soil water within the root-zone were developed that
also minimized leaching below the root-zone. A balance between pre-plant
and in-season nitrogen management was identified for optimal production
of high quality processing potatoes. Tuber yields as well as quality
were not influenced by variable rates of pre-plant N or total N over the
growing season, but since nitrate leaching is a concern in coarse
textured soils, application of low rates of pre-plant N under irrigation
was determined to minimize leaching losses without any negative impact
on the tuber yield or quality. These results can be extrapolated to
other potato production regions on coarse textured soils to maintain
optimal production and further develop nitrogen and irrigation best
management practices. **ARS Locations & Cooperators**: Prosser.
**Selected Refereed Publications**: Alva et al., 2002. Alva et al.,
2002. Alva et al., 2003. Redulla et al., 2002. Alva, 2004a. Alva, 2004b.

[]{#__RefHeading___Toc147540322 .anchor}**6. Precision Management
Approaches.** Farming operations are a complex mixture of activities
with numerous interdependent decisions and tasks. Once, it was enough to
make a decision and then hope for the best results. Today it is
necessary to know which combinations of decisions are the most cost
effective. This requires the application of one or more methods of
analysis to make an evaluation, including at times simulation models as
a part of the analysis process. Research accomplishments include new
sources of spatial data for geographic information system mapping, new
and improved methods of GIS map interpretation, and new uses for mapped
spatial data for decision making.

[]{#__RefHeading___Toc147540323 .anchor}**Development of tools to
rapidly assess crop status.** Rapid measurement of crop status is
critical for real-time management practices. However, traditional
methods of acquiring information from the field are time and
labor-intensive, and limited in coverage area. A range of tools are
being developed for timely, accurate, and straightforward determination
of crop and soil status for use by producers in crop management. Aerial
videography and ground-based remote sensing systems have been developed
that allow rapid, area-wide measurement of crop status. These are being
used to develop indicators of tarnished plant bug infestation using
several vegetation indices, and to indicate crop water status.
Analytical tools developed by the team for rapid assessment of
reflectance imagery allow researchers to utilize the entire spectral
information from scanned crops, delineate physiological, morphological
and edaphic indicators of crop status, and explore potential
interactions contributing to the canopy reflectance. This research is a
component accomplishment supporting systems research in cotton
production. As these sampling methodologies mature and are adopted into
production systems, it is anticipated that substantial benefits will be
realized by producers through reductions in labor-intensive data
collection procedures required for precision applications, and the
generation of timely, accurate maps of crop and soil status for
development of management plans based on potential crop performance and
profitability. **ARS Locations & Cooperators:** Stoneville, Mississippi
State University, and Texas A&M University. **Selected Refereed
Publications:** Sassenrath et al., 2005a. Sassenrath et al., 2005b.
Sassenrath et al., 2003. Tarpley et al., 2003. Thomson et al., 2002.

[]{#__RefHeading___Toc147540324 .anchor}**Sub-field management zones for
improved crop nutrient utilization.** Because many crop production
fields are spatially variable for both soil nutrients and crop nutrient
needs, conventional uniform fertilizer rates often exceed requirements
for some field areas. In response to requests from farmers and
consultants, we developed a decision aid to quickly process map
information into management zones for variable-rate nutrient
applications. The *Management Zone Analyst* (MZA) software uses
quantitative, geo-referenced field information to mathematically divide
a field into natural clusters or zones that are used to determine the
optimal number of management zones for each field. Our approaches and
software are widely used by researchers, commodity organization
representatives, and agricultural consultants from at least 39 states
and 35 foreign countries. Our prior work in the area of management zones
was a key factor in the awarding of the project, *Implementation and
Validation of Sensor-Based Site-Specific Crop Management* by the USDA
Initiative for Future Agricultural and Food Systems. **ARS Locations &
Cooperators:** Columbia, University of Missouri, ARS-CSWQRU, University
of Illinois, Foundation for Agronomic Research. **Selected Refereed
Publications:** Fraisse et al., 2001. Clay et al., 2002. Renschler et
al., 2002. Number range CHAPTERFridgen et al., 2004. Kitchen et al.,
2005.

[]{#__RefHeading___Toc147540325 .anchor}**Mapping soil compaction to
identify field areas for precision tillage.** Soil compaction plagues
many producers in the Southeast U.S. Conservation tillage systems offer
fewer opportunities for correcting soil compaction due to the reduced
traffic allowed in fields. The time-consuming process of obtaining soil
compaction measurements across a field with a soil cone penetrometer
prompted the creation of a machine to measure soil compaction on a
continuous basis. Coupling the *On-the-go Soil Strength Sensor* (OSSS)
with site-specific GIS technology allows maps of soil compaction to be
created. Because the cost of subsoiling can be expensive, soil
compaction maps allow site-specific tillage to be applied at precise
depths where needed, significantly reducing tillage power requirements
and fuel costs. Improvements in technology necessary to map fields for
soil compaction as well as the development of implements that adjust
their tillage depth 'on-the-go' should contribute to a more energy
efficient food production system. **ARS Locations & Cooperators:**
Auburn, Oxford, Watkinsville, John Deere and Company, USDA-NRCS, and
Auburn University. **Selected Refereed Publications:** Hall and Raper,
2005. Raper, 2005. Raper et al., 2005a. Raper et al., 2005b.

[]{#__RefHeading___Toc147540326 .anchor}**Soil maps guide soil sampling
for microbial properties.** Soil microorganisms are involved in carbon
and nutrient cycles, soil aggregate formation and stabilization, and in
the spread and prevention of crop diseases. Soil microbial properties
are known to exhibit high spatial and temporal variability that greatly
complicate their use in directing agricultural management. If soil
microbial properties variability could be considered as a part of soil
sampling schemes, it may possible to better understand the effect of
management on soil microbial properties and how these influence crop
production. It was shown that soil types delineated on soil maps can
serve as initial demarcations for areas within a field that may have
varying soil microbial properties, and it is important to consider
sub-map unit variability when measuring soil microbial properties. This
research is providing information to understand the impact of cropping
systems on soil microbial properties. **ARS Locations & Cooperators:**
Beltsville, Warren Wilson College, and University of Maryland.
**Selected Refereed Publications:** Cavigelli et al., 2005.

[]{#__RefHeading___Toc147540327 .anchor}**Mapping soil electrical
conductivity to understand sub-field grain production variability.**
Farmers and consultants want tools to help them understand yield
variation across fields as a way to apply only needed fertilizers and
other agricultural chemicals. Soil electrical conductivity (EC) has been
shown related to grain production, but producers using commercially
available EC sensors have raised questions about data collection and
interpretation procedures. The value of different data collection
procedures on accuracy have been compared using results from two types
of commercial EC sensors. The research documented the relationships
between EC and soil properties, both within specific soil associations
and over multiple states. The correspondence between EC and grain yields
has been related to both environmental and profitability issues, as well
as used to facilitate the use of EC measurements to understand soil
variations that impacts subsurface hydrology and optimum application
rates of fertilizers and chemicals. Guidelines and information have been
disseminated to farmers, consultants, and researchers across the U.S.
and internationally. The two largest manufacturers of EC sensors for
agriculture cite numerous research reports as reference material for
their customers. **ARS Locations & Cooperators**: Columbia, Ft. Collins,
University cooperators in Missouri, Illinois, Wisconsin, Michigan State,
Iowa State, and South Dakota State, Veris Technologies, MFA, Inc., and
numerous producers. **Selected Refereed Publications:** Kitchen et al.,
2003. Sudduth et al., 2003. Officer et al., 2004. Jung et al., 2005.
Kitchen et al., 2005. Sudduth et al., 2005.

[]{#__RefHeading___Toc147540328 .anchor}**Sensing technology to improve
nitrogen application accuracy.** Over-application of nitrogen fertilizer
is a major problem in the Midwestern United States resulting in
unnecessary production costs and contributing to water quality problems.
Two site-specific management approaches based on crop canopy reflectance
with ground-based or remote sensing and ultra-high resolution aerial
images to predict nitrogen fertilizer needs across variable fields have
been pursued. Optimal Applications rates would increase profit \$15 per
acre. Additional research using ground-based reflectance sensing systems
is in process. **ARS Locations & Cooperators**: Columbia, Lincoln,
Oklahoma State University, University of Missouri, NTech Industries,
Holland Scientific, MFA, Inc., John Deere, and Missouri producers.
**Selected Refereed Publications:** Scharf et al., 2002. Scharf et al.,
2005.

[]{#__RefHeading___Toc147540329 .anchor}**Sensing technology for
improved soil compaction measurements.** Soil compaction is generally
estimated by soil strength or mechanical resistance measurements and is
difficult to efficiently assess within fields using current methods. One
obstacle is simultaneously obtaining soil water content data to
standardize strength measurements. A prototype soil cone penetrometer
was developed that incorporated a near-infrared (NIR) reflectance sensor
to measure soil water content. However, because penetrometers collect
discrete point data, the spatial variability of compaction over short
distances makes it difficult to accurately assess variability with a
reasonable number of samples. To overcome this obstacle, a soil strength
sensor was evaluated that that could simultaneously integrate data from
five depths while moving across a field. The new sensor allows more
thorough examinations of the relationship between crop yield and
compaction and further site-specific compaction management. When
commercialized, this 'on-the-go' sensor will also benefit practitioners
on farms. A cooperative research and development agreement for
additional development of the NIR sensing technology has been
established. **ARS Locations & Cooperators**: Columbia, Ames, University
of Illinois, University of Missouri, University of California,
University of Nebraska, John Deere, Veris Technologies, and Missouri
producers. **Selected Refereed Publications:** Number range CHAPTERChung
et al., 2004. Hummel et al., 2004. Sudduth et al., 2004. Chung et al.,
2005. Chung et al., 2006.

[]{#__RefHeading___Toc147540330 .anchor}**Sensing to improve nitrogen
application accuracy.** Research has shown that *Ion-Selective Field
Effect Transistor* (ISFET) technology can rapidly analyze nitrate
content in soil extracts and has demonstrated a method of rapidly
extracting nitrate from a soil sample. Additionally, a usable
combination of ion-selective membranes and extracting solution has been
identified. Integrating these components into an automated soil sample
collection and analysis system would provide a low cost 'on-the-go'
rapid measurement technique that would automate the pre-side dress
nitrate test. Approaches to assess varying nitrogen fertilizer needs,
coupled with variable-rate fertilizer application, can potentially
impact both the economics of corn production and the environment of the
Midwest. **ARS Locations & Cooperators**: Columbia, University of
Illinois, and Iowa State University. **Selected Refereed Publications:**
Number range CHAPTERPrice et al., 2003. Kim et al., 2006. In press

[]{#__RefHeading___Toc147540331 .anchor}**Understanding within-field
grain yield variability.** Fundamental to precision agriculture
management is accurate measurement of spatial yield variability and
effective methods to relate that yield variability to variations in
other site properties. Several approaches were developed to combine
yield monitor data with inherent errors with techniques to screen and
filter these data. Filtered yield monitor data have been related to site
properties using path analysis, nonparametric statistics, and artificial
neural networks that resulted in yield estimation models of variable
accuracy from year to year. Application of *CERES-Maize* and
*CROPGRO-soybean* models to estimate within-field yield variation on
claypan soils identified needed improvements. Analysis of yield data
collected on 12,000 acres over three years showed corn, soybean, and
wheat yield variability was generally severe, widespread, and
persistent. The greatest impact to date is the widespread use of the
publicly available software that implements yield data filtering
techniques. The software has been downloaded 500 times and numerous
responses from users have commented about the usefulness of this
product. **Locations & Cooperators**: Columbia, Florence, Mapshots,
Inc., University Cooperators in Missouri, Illinois, Wisconsin, Michigan
State, Iowa State, and South Dakota State, and several Missouri
producers. **Selected Refereed Publications:** Number range CHAPTERChung
et al., 2002. Number range CHAPTERDrummond et al., 2003. Number range
CHAPTERWang et al., 2003. Hong et al., 2004. Chung et al., 2005. Sadler
et al., 2005.

[]{#__RefHeading___Toc147540332 .anchor}**Experimental designs for large
commercial field precision applications.** During a production season,
many recommendations are necessary for producing the crop and impacts of
these decisions need to be assessed to determine the best configurations
of precision applications. A topologically based general linear mixed
model approach was developed for the analysis of site-specific and
traditional management practice effects on commercial farms. The
geometries of farm equipment that are smaller than the largest machine
create smaller experimental units nested within the larger ones.
Geographic Information System (GIS) processing and a general linear,
mixed-model approach, provides test statistics based on topological
relationships among agricultural topography features. The analysis
results provide feedback information to producers and consultants for
future production seasons. The utility of the process has been
demonstrated by completing the analysis of several commercial-field,
site-specific experiments, which previously were not able to be analyzed
by traditional statistical methods. A recent workshop was held to
communicate selected results from these analyses to other investigators
within the Mid-South Cotton Belt. As the analysis method is adopted by
other investigators, better research of commercial field experiments
will result, ultimately benefiting producers and researchers across
several states. **ARS Locations & Cooperators**: Mississippi State,
Stoneville, Mississippi State University, and Milliken and Associates.
**Selected Refereed Publications**: Willers et al., 2004.

[]{#__RefHeading___Toc147540333 .anchor}**Development of Site-Specific N
Indices for Precision N Management**. Uniform N management is practiced
throughout the Pacific Northwest Dryland Cropping region and much of the
world resulting in large inefficiencies of N fertilizer use. Lack of
decision support tools for site-specific N management has led to little
adoption of available precision agricultural technologies. N Indices
were used to diagnose the N use and agronomic performance of wheat
across heterogeneous field conditions.  These indices are based on
field-scale information that can be collected by farmers with currently
available technologies: wheat yield, protein and applied N fertilizer.
These variables were used to quantify N use efficiency and classify
wheat performance into 5 distinct classes.  The classes range from N
that was managed efficiently (Class 1) to N management that resulted in
substantial losses to the environment (Class 5).  The classification
system was used to spatially map the performance of N management
practices across agricultural fields.  The N indices and classification
system will be useful to farmers for evaluation and diagnoses of
practice performance and for formulating more efficient N management
practices.  Currently, the N indices are being field tested to evaluate
their effectiveness as a precision N management decision support tool.
If successful, the estimated reduction in fertilizer N input for the
region is 20 to 50%. **ARS Locations & Cooperators**: Pullman,
Washington State, University, McGregors Farm Supply, Wilber-Ellis,
Monsanto, John Deere, Case New Holland. **Selected Refereed
Publications:** Huggins and Pan. 2003.

[]{#__RefHeading___Toc147540334 .anchor}**7. Integrating crops and
livestock for best benefits.** Many livestock producers operate on
relatively narrow profit margins, making production efficiency
particularly important. Although the potential for using diversification
to reduce risk, reduce production costs, and increase profits is well
understood by producers, most focus their efforts and specialize on
either crop or animal production because integrated farming requires a
wider knowledge base. A number of projects are working to provide the
research-based information that producers need to efficiently manage
integrated crop-livestock operations for reduced production costs and
increased profits.

[]{#__RefHeading___Toc147540335 .anchor}**Integrated crop--livestock
production systems for the southeastern U.S**. Multiple ARS locations
and university colleagues have worked together to develop a conservation
tillage system for incorporating cotton-peanut production with
winter-annual grazing. In research in the Southern Piedmont, grazing
cover crops did not alter grain production but did increase system
productivity due to animal gains. Preserving organic matter at the soil
surface was important to mitigate potential compaction from animal
traffic. In the Coastal Plain, profit was 2-3 times greater when cotton
or peanut was grown following 80 days of stocker grazing on oat or
annual ryegrass cover crops, than in conventional cotton or peanut
systems. Profits were maximized on these soils by using some type of
non-inversion deep tillage to alleviate compaction. **ARS Locations &
Cooperators**: Auburn and Watkinsville, Auburn University, USDA-NRCS,
and Alabama Cooperative Extension Service. **Selected Refereed
Publications:** Siri-Prieto et al., 2006. In press.

[]{#__RefHeading___Toc147540336 .anchor}**Tillage requirements for
winter-annual grazing rotations.** Integrating livestock with
cotton-peanut rotations may offer profitable alternatives for producers,
but could result in excessive soil compaction that severely limit
yields. A three-year field study developed a conservation tillage system
for integrating cotton-peanut production with winter-annual grazing to
maintain or improve soil quality and increase profitability. Net returns
from winter-annual grazing were \$64 to \$83 per acre per year. Grazing
increased soil compaction to the 4-in depth, but using conventional
surface tillage or deep tillage reduced compaction and increased soil
water removal by cotton and peanut, compared to strict no-tillage.
Strict no-tillage resulted in the lowest yields (23% and 39% less than
the mean for cotton and peanut, respectively) and non-inversion deep
tillage was required to maximize yields with no-surface-tillage. The
results of this work indicate that producers in the region can maximize
profits by integrating winter-annual grazing with cotton and peanut
using non-inversion deep tillage in conservation tillage systems. This
system allows producers to raise revenue during winter months without
sacrificing cotton and peanut yields. **ARS Locations and Cooperators:**
Auburn, Watkinsville, Auburn University, Alabama Agricultural Experiment
Station, NRCS. **Selected Refereed Publications:** none.

[]{#__RefHeading___Toc147540337 .anchor}**Modified hay production system
improves ruminant feed intake.** A simple modification to alfalfa hay
harvest timing improved efficiency and increased economic viability
through optimizing herbage soluble carbohydrates. Due to the diurnal
fluctuation in photosynthesis, hay cut in the afternoon had the greatest
sugar accumulation for alfalfa. Cattle, sheep, and goats preferred hay
cut in the afternoon over the corresponding morning hay when offered a
choice, and measures of forage quality were also greater for hay cut in
the afternoon. Along with the preference, there was an increased daily
intake of the afternoon harvested forage by goats and cattle; goats
digested the afternoon forage to a greater extent than cattle. Similar
results were not found for switchgrass in the southeast, probably due
the different kind of crop and climate. Due to the simplicity of the
technology, measurable increases in forage quality, and labor advantages
from later-in-the-day haying operations, adoption has been extensive
with over 80% of alfalfa growers surveyed responding that they were
adopting the technology. Adoption is proceeding especially rapidly in
western USA haymaking regions due to information disseminated by
extension, grower organizations, and popular press articles. **ARS
Locations & Cooperators**: Watkinsville, Raleigh, and Kimberly,
University of Idaho, and Montana State University. **Selected Refereed
Publications:** Burns et al., 2005. Fisher et al., 2002. Fisher et al.,
2005.

[]{#__RefHeading___Toc147540338 .anchor}**Improved pasture utilization
increases dairy cow feed efficiency.** It has been estimated that
managed intensive rotational grazing is practiced on 10 to 25% of dairy
farms in the Midwest and Northeast. Inadequate intake of dry matter is a
primary factor limiting milk production of such grazing-based dairy
systems. Since grazing cows are dependent upon pasture for the majority
of their feed requirements, optimum utilization of grasses at the
appropriate stage of maturity is essential to maximizing intake.
Preliminary research indicates that pasture grasses differ significantly
in the distribution and quality of herbage from the top to the bottom of
the canopy. For example, the upper third of a meadow fescue canopy is
300% more dense during the summer than orchard grass, and is 5% more
digestible. Improved intake of higher quality herbage can improve the
profitability and sustainability of grazing-based dairy systems by
reducing the need for expensive grain supplements. **ARS Locations &
Cooperators**: Madison and University Park. **Selected Refereed
Publications:** none.

[]{#__RefHeading___Toc147540339 .anchor}**Tannins may increase dairy
profits and enhance environmental quality.** Production and feeding of
tannin-containing forages on dairy farms could increase productivity and
profitability while reducing environmental impacts. When birdsfoot
trefoil with condensed tannin was fed in place of tannin-free alfalfa,
dairy cattle produced 15% more milk and excreted 20% less urinary
nitrogen -- a form of nitrogen readily lost to the atmosphere. Models
predict an increase in net returns of 7 to 12% and nitrogen loss
reductions of 6 to 25%. In this initial analysis, tannins reduced the
need for protein supplements by up to 60%, and increased the value of
alfalfa silage by \$23 and alfalfa hay by \$11 per ton of dry matter.
The potential worth to the dairy industry is \$300 million per year.
Ongoing feeding, field, and laboratory trials, along with computer
simulations will identify optimal forage tannin levels and management
practices for enhancing protein utilization and nitrogen cycling on
dairy farms. **ARS Locations & Cooperators***:* Madison, University
Park, Beaver, and university partners in Michigan and Utah*.* **Selected
Refereed Publications:** Hymes-Fecht et al., 2004. Misselbrook et al.,
2005.

[]{#__RefHeading___Toc147540340 .anchor}**Integrating annual forages
into a Great Plains beef production system.** Fed forage to livestock
over winter is the single largest cost for producers in the northern
Great Plains. Research has evaluated the potential of integrating
swathed annual forages into a beef production system to reduce winter
feeding costs. Costs were lowered by \$0.24 per animal per day compared
to a dry-lot, without adverse effects on middle-aged beef cow
production. About half of the nitrogen used for protein production was
derived from sources other than commercial fertilizer. The trends in the
fourth year of the project suggested that livestock may enhance forage
and grain production in the crops fields. This information may lead to
lower-cost integrated crop-livestock systems. ARS **Locations &
Cooperators**: Mandan. Liebig et al., 2006. **Selected Refereed
Publications:** Tanaka, et al., 2005. Liebig et al., 2006.

[]{#__RefHeading___Toc147540341 .anchor}**Dairy herd management enhances
nutrient cycling.** Optimal nutrient use on dairy farms depends on what
is fed to cows, herd management, and the balance between livestock
numbers and land area available for feed production and manure
application. Research has discovered critical, previously unknown
relationships between dairy herd size, cropland area, and a farm's
ability to grow feed and recycle manure nutrients through crops, and
between farm size, livestock housing, herd management, and the amounts
of manure collected and spread on cropland. A six-year field trial
discovered that corralling livestock in fields between cropping periods
captures and recycles more manure nutrients, which increases yields
substantially, often for 2-3 years, and requires less labor than
conventional confinement systems whereby manure is hauled, and most
urine N is lost from barns. Corralling dairy cows on cropland is
becoming increasingly attractive to farmers during the current era of
escalating energy and fertilizer N costs. Based on these findings,
regulatory agencies are considering use of animal:cropland ratios as
indicators of whole-farm environmental performance, and as an additional
factor to include in Comprehensive Nutrient Management Planning. The
discovery that herd management on small farms leads to less manure
collected than on large farms is refocusing policy towards special
assistance to small farms in managing manure in barnyards and other
outside areas where cattle congregate and manure goes uncollected. **ARS
Locations & Cooperators**: Madison, University of Wisconsin, Utah State
University, and the Food Alliance. **Selected Refereed Publications:**
Powell et al 2005. Saam et al 2005.

[]{#__RefHeading___Toc147540342 .anchor}**On-farm research improves
nutrient management on dairy farms.** Understanding the challenges
livestock producers face in nutrient management is critical to focus
research, extension, and policy on information and technologies to
create opportunities that enhance farm profits and the environment.
On-farm research aimed at improving the understanding of how farmers
manage nutrients in realistic settings showed that most Wisconsin
producers feed excessive amounts of P to lactating dairy cows, which
increased dramatically the cropland needed for recycling manure and also
affected greatly the duration before all cropland attained excessive
levels of soil test P. The on-farm research questionnaires and other
instruments developed in this study have been adapted for use in Iowa,
New York, Ohio, Pennsylvania, Wisconsin, and Australia, and many of the
on-farm research findings have been incorporated into
nationally-distributed outreach materials. **ARS Locations &
Cooperators**: Madison and University of Wisconsin. **Selected Refereed
Publications:** Powell et al 2002. Powell et al 2005.

[]{#__RefHeading___Toc147540343 .anchor}**Refined dairy diets enhance
profits and the environment.** The sustainability of U.S. animal
agriculture increasingly depends both on profitability and compliance
with manure management regulations. Research has shown important
relationships between dairy feeding practices, manure nutrient
excretions, and the impact of these factors on profitability and
environmental outcomes. The prevailing industry practice of feeding
mineral supplements to lactating dairy cows increases total-phosphorus,
water-soluble-P, and heavy metal concentrations in manure beyond what
can be effectively recycled on cropland after manure application. These
results have been incorporated into national outreach materials to
change producer practices, and recent surveys of nutritionists and feed
companies across Wisconsin show significant reductions in dietary P
levels. The saving to U.S. dairy farmers is \$30-35 million annually,
and has the potential of an additional savings of \$65-70 million.
Mitigating environmental risks associated with reduced N and P loss from
dairy farms due to reduced dietary N and P levels are "win-win"
situations that will continue to enhance the profitability and
environmental impacts of dairy farming in the US. **ARS Locations &
Cooperators**: Madison and University Park. **Selected Refereed
Publications:** Ebeling et al., 2002. Li et al., 2005. Misselbrook et
al., 2005. Powell et al., 2006.

[]{#__RefHeading___Toc147540344 .anchor}**Problem Area B. Systems,
Strategies, and Tools to Reduce Agricultural Risks.** The technology
developed to address this goal include entire system analyses and the
development of decision aids based on research results to guide a
producer to an integrated decision. Simulation models of plant growth
processes are also included to help predict likely responses if
management changes are made by producers. Large scale techniques such as
remote sensing and GIS provide field level information on crop status,
give access to historical information that can be used to evaluate land
use practices, and determine the best approaches to meet the specific
needs of producers.

[]{#__RefHeading___Toc147540345 .anchor}**1. Alternative Risk-Aversion
Production Systems.** Research is being done to demonstrate certain
production systems are better than others in reducing the chances of
financial risk to producers.

[]{#__RefHeading___Toc147540346 .anchor}**Reducing tillage and
diversifying crop rotations can reduce risk to Northern Corn Belt
farmers.** Despite national trends toward adoption of conservation
tillage, farmers in the Northern Corn Belt continue to use intensive
tillage. In addition, there has been a reduction in crop diversity in
this area. Farmers need assurances that using new production practices
will not put them at risk of financial loss. ARS has addressed the
problem of reducing barriers to the adoption of more sustainable
cropping systems using long-term studies to evaluate the effects of
cropping systems on economic risk. The research showed that ridge
tillage increased profitability, reduced fuel and labor use, and reduced
economic risk relative to conventional tillage for a corn and soybean
rotation. The research also showed corn rotations including soybean,
spring wheat, and alfalfa instead of continuous corn production were
valuable risk management tools when government payments and crop
insurance are not available. However, when growers choose to use both
government programs and crop insurance, the relative benefits of crop
diversification in reducing risks are decreased. Recent research results
showed that no-till and many strip tillage systems increased
profitability and reduced fuel use compared to moldboard plow and chisel
plow tillage systems for a corn and soybean rotation. The research is
helping assure Northern Corn Belt farmers who want to adopt more
sustainable production practices that reduce tillage and diverse crop
rotations can reduce economic risks and complement other risk management
tools including government programs and crop insurance. The research can
also help policy makers find creative ways to design programs that
provide economic incentives for producers to adopt conservation
practices. **ARS Locations and Cooperators:** Morris, Brookings.
**Selected Refereed Publications:** Archer et al., 2002.

[]{#__RefHeading___Toc147540347 .anchor}**Designing low-risk dryland
cropping systems for the Northern Great Plains.** Most dryland small
grain enterprises in the Northern Great Plains are not economical
without Federal transfer payments. A major agronomic concern is the
limited diversity of crops in this semi-arid region that is subject to
frequent drought. To replace spring grain-fallow systems, a team is
developing intensive, no-till systems that increase crop diversity using
new rotational sequences, reduce operation costs, and minimize
agrochemical usage. Research is also determining short-term means for
controlling weeds at the onset of intensive low-till or no-till farming
efforts. The agroecological approach is showing that manipulation of
planting times, straw height, herbicide programs and crop selection from
year to year can substantially reduce pesticide use and conserve
moisture, while also increasing carbon sequestration and reducing fuel
consumption by growers. Two large-scale, long-term, multidisciplinary
studies were begun in 2004. This research is directed toward
understanding the complexity of these systems to quantify the economic
and environmental benefits of these strategies that reduce risk. **ARS
Locations and Cooperators:** Sidney, Roosevelt and Sheridan County
Conservation Districts, USDA, CSREES, Montana State University,
Roosevelt County Conservation District, Sheridan County Conservation
District, and Mosaic Company. **Selected Refereed Publications:**
Caesar-TonThat et al., 2001. Sainju et al., 2005. Goosey et al., 2005.
Sainju et al., 2006a. Sainju et al., 2006b.

[]{#__RefHeading___Toc147540348 .anchor}**Holistic approach to farm
planning and conservation programs improves profitability and enhances
natural resources conservation.** There is need to find ways to increase
farm environmental benefits while enhancing economic viability. This is
particularly true in the Drift Prairie Region of the U.S. where extreme
weather events caused persistent wet conditions and flooding and have
exacerbated already tense relationships between environmental and
agricultural interests. A five-year demonstration project was initiated
to demonstrate the benefits of agricultural-environmental planning and
cooperation. Each of four demonstration farms worked under a whole-farm
plan developed by the producer and a six-member *Resource Analysis Team*
comprised of agriculture and conservation professionals. As a part of
this project, ARS conducted research on the economic performance of the
demonstration farms in comparison to other farms in the region. Research
results showed that farm debt declined significantly for three of the
four farms, and all four farms had less indebtedness than regional
averages. Conservation was a dramatically larger share of total
government and conservation payments than regional averages, and these
payments went directly toward purchasing residue conserving equipment
resulting in potentially long-lasting shifts in production practices.
Other parts of the project showed wildlife, water quality, and wetland
carbon storage benefits and reductions in erosion. The research
generated support among the producer-participants and involved many
government and non-governmental groups at the Federal, State, and local
levels, which will help promote conservation activities in the region.
This project also provides a template for policy makers to use in
designing future conservation programs for the region. **ARS Locations
and Cooperators:** Morris and North Dakota Natural Resources Trust.
**Selected Refereed Publications:** Clancy et al., 2006.

[]{#__RefHeading___Toc147540349 .anchor}**2. Models to Predict At-Risk
Conditions and Best Responses to Management.** Specific decision support
tools are being developed to help producers identify the best ways to
produce their products with the least amount of economic risk.

[]{#__RefHeading___Toc147540350 .anchor}**Crop damage assessment tool
for field-scale decisions.** Crop damage assessment tools are needed to
show producers which portions of their fields consistently produce
non-profitable yields and to provide the Risk Management Agency (RMA)
with ways to assess field-scale crop damage amounts. ARS Scientists in
Iowa developed a tool based on the integration of field-scale
geographical information system layers of soil types, topography,
harvested yield, and remote sensing images. The researchers found that
the remotely sensed data provided a measure of crop biomass needed to
estimate potential crop yield. This tool is being incorporated into a
process for producers to use as part of the field-scale crop damage
assessment for RMA. **ARS Locations & Cooperators:** Ames. **Selected
Refereed Publications:** Pinter et al., 2003. Hatfield et al., 2005

[]{#__RefHeading___Toc147540351 .anchor}**Research results used to
identify profitable combinations of potato cropping practices for the
Northeastern U.S.** ARS researchers have integrated soil, plant disease,
crop productivity, and economic research to develop the *Potato Systems
Planner* decision-support software. The software weaves together eight
years of research covering 14 cropping systems findings on yield,
quality, profitability, grower risk, nutrient cycling, soil-born
diseases, and soil microorganisms. Also, an *Economics Calculator* based
on the same input as required for loan applications by the USDA Farm
Service Agency, helps growers estimate profitability of each cropping
system. Over 750 copies of the *Potato Systems Planner* have been
distributed to growers and scientists from 21 states, seven Canadian
provinces, and eight countries since 2005. **ARS Locations and
Cooperators:** Orono, Maine Potato Board National Potato Council,
University of Maine. **Selected Refereed Publications:** Franzluebbers
et al., 2001. Larkin et al., 2003. Griffin et al., 2004. Halloran et
al., 2005. Olanya et al., 2005.

[]{#__RefHeading___Toc147540352 .anchor}**Crop simulation for decision
making in Pacific Northwest potato-based cropping systems.** Tools to
improve nitrogen management for potatoes in the Pacific Northwest are
desirable in view of the concern on non-point source pollution of
nitrate into groundwater in the Columbia Basin production region which
is characterized by sandy soils and possible N inputs in excess of crop
N requirement. The *CSPotato* model was integrated into the multi-year,
multi-crop *CropSyst* simulation model to improve assessments of
nitrogen fate under different fertilizer and irrigation regimes in
potato systems. When the crop in rotation is potato, the potato model
simulates potato growth and development and plant carbon and N balances.
Validated model predictions have shown that 240 to 400 lbs. per acre of
N was unaccounted and therefore could be considered as subject to
leaching. The model will be made available for general use on
Website.**ARS Locations & Cooperators:** Prosser, Beltsville, Washington
State University. **Selected Refereed Publications:** Alva et al., 2003.
Delgado et al., 2005. Alva et al., 2005.

[]{#__RefHeading___Toc147540353 .anchor}**On-farm research results in
simple spreadsheet planning tools.** Central Great Plains farmers and
ranchers must manage for regular and cyclic drought, lower commodity
prices, increased input costs. These factors coupled with government
programs and crop insurance options make optimal decision making
difficult. A program of on-farm research for testing *GPFARM* and
related technologies was initiated with over 100 visits made by
cooperators to collect whole farm information. This effort used in the
development of the new *iFARM* decision support tool to help producers
find the optimal balance between crops, insurance type and level of
coverage, inputs, and lease options. The spreadsheets have been well
received and the Colorado Association of Wheat Growers has made the
spreadsheets available on their Website. **ARS Locations &
Cooperators**: Fort Collins, Decision Commerce Group, Farm Credit of
Southern Colorado, Colorado State University, and USDA-NRCS. **Selected
Refereed Publications:** Ascough II, et al., 2002. McMaster et al.,
2002.

[]{#__RefHeading___Toc147540354 .anchor}**The economics of crop rotation
sequences and technology transfer to producers.** Adequate rotation time
between peanut crops is essential for maximizing peanut yield.
Maximizing yield output is not the same as maximizing economic returns,
and decisions on the best crop rotation system must consider the
profitability of the system as a whole. The *WholeFarm* farm planning
system was developed to assist growers in developing formal whole farm
plans and has been distributed to producers in over 30 states. The
Cross-Commodity Breakeven Price Matrix (CCBPM) is a recent addition to
*WholeFarm* and will calculate the required price changes in crop grown
in rotation with peanuts that would justify shortening or lengthening
the rotation time. The CCBPM provides producers valuable information
necessary to make farm planning decisions that incorporate scientific
data with farm specific data. This optimization system has been used as
an agricultural prediction component for a project supported by NASA
determining the effects of long-term global change. **ARS Locations &
Cooperators:** Dawson and Watkinsville. **Selected Refereed
Publications:** Lamb et al., 2005. Sternitzke et al., 2000. Butts et
al., 2004.

[]{#__RefHeading___Toc147540355 .anchor}**Producers can evaluate the 100
different crop sequences for the Northern Great Plains.** Northern Great
Plains producers need a simple way to evaluate the strengths and
weaknesses of various cropping sequences. Scientists at the Northern
Great Plains Research Laboratory in Mandan, North Dakota, developed the
easy-to-use *Crop Sequence Calculator*. The *Crop Sequence Calculator*
contains information on production economics, soil water use, surface
soil properties, plant diseases, weeds and insects. Information for the
calculator was gathered from crop sequencing experiments conducted at
the Mandan location. Over 12,000 copies of the CD have been distributed
to producers, extension agents, consultants and university educators.
**ARS Locations & Cooperators:** Mandan. **Selected Refereed
Publications:** none

[]{#__RefHeading___Toc147540356 .anchor}**Decision aids provide guidance
to improve production efficiency, reducing input costs, and increase
profitability.** Producers face many management decisions that impact
profitability and potential environmental impacts within a season. The
*Nitrogen Decision Aid* provides producers information quickly and in a
user-friendly format that enables them to make nitrogen use decisions
efficiently. The *Nitrogen Decision Aid* utilizes weather, soil, and
management data to estimate nitrogen side-dress needs and has been
downloaded over 1400 times since its release in 2000. *WeedCast*
utilizes weather, soil, and management information to estimate crop
emergence time and weed growth estimates for 18 species, thus improving
weed control by optimizing the timing of weed control measures.
*WheatScout* builds upon the *WeedCast* model and combines information
on wheat growth and herbicide application windows to assist producers in
selecting herbicides and estimating optimal application timing and rate.
*SeedChaser* allows farmers to evaluate the impact of tillage on
resulting weed seed bank distribution and surface applied chemical
incorporation following tillage. In addition, the *WEEDTURF* turf grass
weed management model has been developed. **ARS Locations &
Cooperators:** Morris, Fort Collins, Universidad Nacional de Rosario,
University of Western Australia, and Growth Stage Consulting, Inc.
**Selected Refereed Publications:** Ekeleme et al., 2005. Ekeleme et
al., 2004. Masin et al., 2005.

[]{#__RefHeading___Toc147540357 .anchor}**Interactive decision aid
developed to estimate stem rust disease development.** Stem rust is the
most important and damaging disease of grasses grown for seed in the
Pacific Northwest. Over 400,000 pounds of fungicide are applied annually
at an estimated cost of \$10-million. The disease can be managed with
fungicides that are typically applied on a 14-day schedule which result
in more applications than required in most years. In addition, the
effectiveness of fungicide sprays for rust control depends on knowing
when to start spraying. An interactive decision aid to estimate stem
rust disease development has been developed that collects real-time
weather data from numerous grass seed fields and estimates the potential
for stem rust development. Users can choose a location, enter their
observed initial disease levels, and get an estimate of disease
development in the presence and absence of fungicides for any date. The
Web-based model allows managers to assess the timing and benefits of
fungicide application and potentially to reduce costs. **ARS Locations &
Cooperators:** Corvallis, Western Farm Service, and Oregon State
University Plant Protection Center. **Selected Refereed Publications:**
Pfender et al., 2003. Pfender et al., 2004a. Pfender et al., 2004b.
Pfender et al., 2006.

[]{#__RefHeading___Toc147540358 .anchor}**How and why weeds differ
between fields and among years.** Geographic information system
technology can be used to monitor changes in weed distribution patterns
over space and time so the seriousness of weed problems can be
determined and to identify linkages between specific agronomic practices
and weed infestations. ARS Scientists developed procedures to
georeference ten years of crop production and weed incidence data from a
proprietary non-spatial database, and then created a georeferenced
database to study changes in weed distribution and severity. Application
of this technology led to identification of the five most aggressive
weed species in established perennial grass seed stands, quantification
of their aggressivity, and recognition that increased time out of grass
seed production decreased the severity of four weed species and
increased the severity of ten others. Quantifying changes over time in
severity of major weeds has provided the grass seed industry with
information critical for focusing future weed control research efforts,
and for informing regulatory agencies in their decision making regarding
herbicide registration requests. **ARS Locations & Cooperators:**
Corvallis and Oregon Seed Services, Oregon State University. **Selected
Refereed Publications:** none.

[]{#__RefHeading___Toc147540359 .anchor}**GLYCIM model increases
irrigation efficiency for Mississippi Delta soybean growers.** Soybean
is an important crop in the Southeastern United States where irrigation
is becoming more widespread. While there are guidelines for irrigation,
a simulation model can allow growers to rapidly evaluate numerous
options for estimating the effects of irrigation timing and amount on
projected yield and harvest date where experiments have not been
conducted. The GLYCIM soybean simulation model was tested with 12
growers over an eight-year period (1991 to 1999) in the Mississippi
Delta region and two years in the Florida PanHandle (2004-2005) for
making pre-season decisions on variety and row spacing selection,
planting date, and in-season decisions for irrigation and harvest
timing. Growers using the model attributed increases in yield up to 29%
and irrigation use efficiency up to 400%. Based on the GLYCIM results,
growers also decided to purchase additional irrigation equipment after
seeing the yield increases due to irrigation predicted by GLYCIM
actually occurred. This research has benefited both soybean farmers and
scientists interested in quantifying environmental effects on soybean
growth and development. **ARS Locations & Cooperators:** Beltsville,
Mississippi State University, University of Maryland, Florida A&M
University. **Selected Refereed Publications:** Ali et al., 2004. Koti
et al., 2004. Reddy et al., 2002. Taylor et al., 2004.

[]{#__RefHeading___Toc147540360 .anchor}**The latest scientific
knowledge and technology incorporated into GOSSYM and GLYCIM.** Many
crop simulation models use empirical relationships that are not
appropriate for estimating plant response to global climate change, are
inaccurate for simulating plant response to environmental stresses, or
require re-parameterization for different locations. Using technology to
measure plant physiological processes, plant responses to environmental
conditions at great detail have been quantified to develop a new
generation model for melon growers in Texas to schedule optimal harvest
times. In addition, a soil process simulator for plant models was
developed for the Web and has been used in a number of studies in
Israel, Germany, Russia, England, and Taiwan. Soil process simulation
models and model based data analysis have also been used to estimate
ground-water recharge for the Nuclear Regulatory Commission to provide
guidance to NRC contractors for accepted monitoring methods of
ground-water. Simple water budget models have been useful to analyze
yield map data and remotely sensed information on leaf area index. This
research benefits agricultural managers, scientists, and policy makers
interested in quantifying environmental factors on crop growth and
yield. **ARS Locations & Cooperators:** Beltsville, Prosser, Ft.
Collins, Riverside, Mississippi State University, and the University of
Maryland. **Selected Refereed Publications:** Kim et al., 2003. Kim et
al., 2004. Kim et al., 2006. Timlin et al., 2002.

[]{#__RefHeading___Toc147540361 .anchor}**Agricultural system-level
models used to help direct field research.** The agricultural system
model Root Zone Water Quality Model (RZWQM) provides a systems approach
for field scientists to simulate various producer management practices.
Over the last five years, several improvements have been made linking
RZWQM with DSSAT (CERES and CROPGRO) plant growth models to provide
users more options in plant growth simulation. Also, RZWQM and SHAW have
been integrated to simulate no-tillage effects on soil moisture and
temperature, and with the GIS application *Maria* to extend applications
to spatially distribute field results. RZWQM has been used to simulate
the effects of weather variability, controlled drainage, and cover crop
components on soil and water quality. **ARS Locations & Cooperators**:
Fort Collins and Colorado State University. **Selected Refereed
Publications:** Hu et al., 2006. Ma et al., 2005. Ma et al., 2006.
Malone et al., 2004. Nielsen et al., 2002. Yu et al., 2006.

[]{#__RefHeading___Toc147540362 .anchor}**Generic interface for crop
simulation models simplifies model use for growers and scientists.**
Graphical user interfaces simplify the use of simulation models and data
management by users. The graphical user interface GUICS was developed
for on-farm use by growers in the Mississippi Delta and the Florida
Panhandle to test the soybean model GLYCIM. In addition to GLYCIM,
several other models were added to GUICS, including MAESTRA, a model of
tree crop growth useful for Nursery Managers, GOSSYM, a mechanistic
cotton model, SIMPOTATO, a model of potato growth, and MELONMAN, a
management model for melon crops. We have had over 100 requests for the
software and have distributed it widely in the United States and
internationally via the Web. **ARS Locations & Cooperators:**
Beltsville, Mississippi State University, Clemson University, and
University of Maryland. **Selected Refereed Publications:** Anbumozhi,
et al., 2003. Bauerle et al., 2005. Taylor et al., 2004.

[]{#__RefHeading___Toc147540363 .anchor}**Web-based planning tools for
conservation managers.** An integrated Web-based conservation planning
tool platform linked to a relational database and served by a Web-based
geographic information system map browser was developed. Automated
conservation planning worksheets were made available to the NRCS State
Office in Portland. Oregon NRCS estimated their conservation planners
save 200 hours of planning time annually through use of automated
worksheets. The Online Agriculture Conservation (OAC) Planning Tool Box
was delivered to the Yolo County (CA) Resource Conservation District to
evaluate conservation education activities. WebGRMS (Germplasm
Management System) software emulating the USDA Genetic Resources
Information Network (GRIN) database demonstrated germplasm managers can
easily make geospatial analyses of germplasm collections without GIS
software training using low-cost, open-source Linux operating system
software. WebGRMS software emulating the USDA GRIN database was also
delivered to the USDA-ARS Plant Germplasm Introduction and Testing Unit
at Pullman. NRCS headquarters and the State Office in Portland are
collaborating in the development of a landowner self-assessment Web tool
to support Conservation Security Program delivery by all state offices.
**ARS Locations & Cooperators**: Corvallis and Oregon State University
Department of Electrical Engineering and Computer Science. **Selected
Refereed Publications:** Steiner et al., 2005. Steiner et al., 2006.

## Problem Area C. Strategies to Expand Market Opportunities.

[]{#__RefHeading___Toc147540365 .anchor}**1. Producing Organic
Products.** Organic production is one of the fastest growing segments of
U.S. agriculture with sales greater than \$12.8-billion that are
increasing more than 20% annually. Increased research efforts by ARS are
needed to see to it that production keeps pace with increasing American
and world consumer demand for organic products, and to ensure the food
product safety. ARS has an established nation-wide network of research
facilities that can address all aspects of organic food, feed, and fiber
production for all U.S. production regions and consumer markets.

[]{#__RefHeading___Toc147540366 .anchor}**Manure use can be managed to
benefit soil biodiversity and reduce potential health risks.** Organic
systems rely heavily on recycling nutrients to crops from animal manure
and soil organic matter. These same nutrients can be sources of ground
and surface water contamination. Use of manure in organic vegetable
systems is a concern due to the potential for contamination by human
pathogens in the manure. ARS researchers found that *Listeria
monocytogenes* (a major gastrointestinal pathogen) present in liquid
dairy manure did not survive in soil beyond 70 days after field
application, and was not present on potatoes harvested from the same
soil. **ARS Locations & Cooperators:** Orono, Maine Organic Farmers and
Gardeners Association, Northeast Organic Dairy Producers Alliance, Maine
Organic Milk Producers, University of Maine, University of New
Hampshire, University of Vermont, Agriculture and Agri-Food Canada,
University of South Carolina, Brookhaven National Laboratory, Savannah
River Ecology Laboratory, Stanford University, University of Delaware,
Alabama A&M University. **Selected Refereed Publications:** Larkin et
al., 2006. Liao et al., 2003.

[]{#__RefHeading___Toc147540367 .anchor}**Improved understanding of
disease management in organic potato systems helps all producers.**
Plant diseases are significant problems in many organic production
systems. It was demonstrated that oregano completely inhibited growth of
the Late Blight pathogen (*Phytophthora infestans*) in the laboratory
and partially inhibited the pathogen in growth chamber studies. Also,
commercially-available biological control organisms such as *Trichoderma
virens* and *Bacillus subtilis* can reduce Rhizoctonia stem canker by
37-75% and black scurf by 11-20%, while increasing potato yield by
15-20%. Similarly, crop rotations of *Brassica* species reduced several
diseases on potato. This research identified several options for
controlling diseases that are now employed by both organic and
conventional growers. **ARS Locations & Cooperators**: Orono, Auburn,
Beltsville, Bowling Green, Clay Center, Lincoln, Madison, Pendleton,
Tifton, Wyndmoor, University of Maine, University of New Hampshire,
University of Vermont, Agriculture and Agri-Food Canada, University of
South Carolina, Brookhaven National Laboratory, Savannah River Ecology
Laboratory, Stanford University, University of Delaware, Alabama A&M
University. **Selected Refereed Publications**: Larkin, 2002. Larkin,
2006.

[]{#__RefHeading___Toc147540368 .anchor}**Organic management practices
and soil biological responses.** Organic strawberry production did not
benefit from mycorrhizal inoculants, although mycorrhiza induced earlier
maturity in tomato and may benefit onion, watermelon, and pepper.
Because of the multiple ecosystem services provided by soil
macro-organisms, understanding the impact of cropping systems on the
abundance and species diversity of soil macro-organisms could help in
designing cropping systems that are less dependent on pesticides to
regulate pest species numbers and activities. Ground beetle relative
abundance, species number, and species diversity were greater in an
organic cropping system than in a conventional chisel-tilled system.
Ground beetle assemblages were very similar in no-till and chisel-till
systems, and were most unique in organic cropping systems. This research
is of particular interest to organic farmers who consider soil
biological activity an important component of their production system,
but do not have scientific information directing their management
decision concerning soil biological communities and their effects on
productivity. **ARS Locations & Cooperators:** Beltsville, Salinas,
Community Alliance for Family Farmers, California Strawberry Commission,
University of California. **Selected Refereed Publications:** Bull et al
2004.

[]{#__RefHeading___Toc147540369 .anchor}**Organic alternatives for
deworming sheep and goats.** Internal parasites of sheep and goats are
becoming resistant to chemical dewormers and organic producers cannot
use chemical treatment. Genetic resistance against parasites was found a
viable approach for parasite control, with St. Croix and Katahdin hair
breeds being more resistant to parasites than Dorper and other wool
breeds. Preliminary results suggest small ruminants ingesting sericea
lespedeza, a condensed tannin-rich forage, had lower populations of the
*Haemonchus contortus* internal parasites. Supplementation with low
doses of copper oxide wire particles appeared to be an effective means
to control *Haemonchus* infestations in small ruminants. Management
protocols that permit only low levels of internal parasites are
essential for organic sheep and goat meat production systems. Further
component and system level research is required to solve problems
related to organic production of small ruminants. **ARS Locations &
Cooperators:** Booneville, Southern Consortium for Small Ruminant
Parasite Control, and University of Arkansas. **Selected Refereed
Publications:** Burke et al., 2002. Burke et al., 2004. Burke et al.,
2006. Shaik et al 2006.

[]{#__RefHeading___Toc147540370 .anchor}**Increasing crop rotation
length and complexity reduces weed pressure and increases crop yields in
organic systems.** Organic farmers have identified weed management as
one of their biggest challenge. In a ten-year study on weed dynamics in
organic and conventional systems, the impacts of weeds on crop yields
and weed seed bank size in corn and soybean decreased as crop rotation
length and complexity increased from one to five years. Weed seed bank
size in the spring was often correlated with weed cover percentage at
maturity the same year, demonstrating that maintaining a low seed bank
by using diverse rotations can lead to improved weed control in organic
crops. During favorable years, corn yield losses due to weeds were less
than 5% in the longest organic rotation, a level similar to that
achieved using herbicides in conventional no-till and chisel-till
systems. This result indicates that with good management, longer organic
crop rotations can function comparably to conventional systems. These
results will be of great benefit to organic farmers and those
considering transitioning to organic cropping when they plan their weed
control strategies. This research has resulted in the establishment of a
Congressionally-mandated cross-location research project with
Pennsylvania State University and the Rodale Institute to conduct a
comprehensive analysis of weed population dynamics in conventional and
organic systems. **ARS Locations & Cooperators**: Beltsville, Rodale
Institute, Pennsylvania State University. **Selected Refereed
Publications**: Teasdale et al., 2003. Teasdale et al., 2004.

#### First Low-Soil Disturbance Organic Cropping System Designed and Tested in Pacific Northwest

Organic farming systems have historically relied on intensive tillage to
establish crops and manage pests. In the Pacific Northwest, the severe
hazard of soil erosion precludes the use of intensive tillage in the
design of sustainable cropping systems. A low soil disturbance organic
system was designed and field-initiated in 2001 at the Palouse
Conservation Field Station. The new organic system, implemented at
field-scales, combines recent no-tillage technology with key cropping
system elements to meet national USDA Organic standards as well as
regional biophysical constraints and economic objectives. After four
years, we show that the integration of no-tillage with organic
technologies is viable and represents a nascent accomplishment as the
system is continually modified and improved each year. Notable system
constraints are primarily fertility related and the system has been
improved to include more legumes. Several farmers have now initiated
conservation tillage-based organic systems and represent the first
farmers to attempt this in the dryland cropping region of the Pacific
Northwest. **ARS Locations & Cooperators**: Pullman and Washington State
University, Pullman, WA. **Selected Refereed Publications**: None.

[]{#__RefHeading___Toc147540372 .anchor}**Cover cropping practices
improve organic weed management.** Weed management is challenging and
expensive in organic crop production. Because it is essential to
minimize weed seed production during all phases of a crop rotation, the
relationship of biomass from common winter cover crops including
cereals, mustard, and legume/oat mixtures on season-long weed
suppression was determined. Within a site, there were few differences in
above ground biomass production by the cover crops, but large
differences in their weed suppressive abilities. Weed suppression was
influenced by seeding rate and cover crop variety. At typical seeding
rates, weed suppression was excellent by mustard and rye, intermediate
for oats, and extremely poor in legume/cereal mixes. Increasing the
seeding rate of the legume/cereal mixes improved weed suppression to
acceptable levels. An additional trial found that the rotary hoe could
reduce weed seed production in winter cover crops by up to 80%. This
research benefits organic producers by providing information that has
helped maximize the benefits of cover cropping and minimize weed seed
production in high-value vegetable crops throughout the year. **ARS
Locations & Cooperators**: Salinas, California Cooperative Extension.
**Selected Refereed Publications**: Brennan and Smith, 2005.

[]{#__RefHeading___Toc147540373 .anchor}**Factors of organic production
affect cover crops and vegetables.** Vegetable production systems that
conform to organic requirements for Oklahoma are being developed from
transplant production time to harvest. The transition period to organic
production was examined for three vegetables. Over time yields increased
during the transition period to organic production, but inputs
requirement remained the same or increased, thus reducing profit. Trials
examining use of corn gluten meal for weed control in non-pungent
jalapeno determined that although there were initial reductions in weed
densities, there were no observable reductions in weed densities or
differences at harvest, compared to the weedy-check treatments. The
certified organic watermelon production system using plastic mulch
rather than acetic acid for weed control had greater weed control and
watermelon yields. The scientists are working closely with local organic
producers, and portions of the systems are being adopted. The Lane
location has the first certified organic acreage in the state of
Oklanhoma. **ARS Locations & Cooperators**: Lane. **Selected Refereed
Publications**: Russo, 2005.

[]{#__RefHeading___Toc147540374 .anchor}**Stale seed bed techniques for
organic vegetable production.** High-value organic vegetable crop weed
management has hand labor costs up to \$1500 per acre. This high cost
and increasing legislative pressure limiting use of weeding labor
necessitates the development of techniques that minimize hand labor for
weed control. ARS scientists in California collaborated with a local
organic farmer to evaluate the effectiveness and cost of six organic
compliant weed management tools to prepare stale seed beds in
high-density vegetable production. These techniques included organic
herbicides, propane flamers, and various cultivation tools. Most
techniques controlled more than 70% of the weeds and cost less than
\$230 per acre. However, the organic herbicide was ineffective and cost
\$1557 per acre. These findings identified effective methods to help
organic producers minimize the need for hand weeding of high value
vegetable crops. **ARS Locations & Cooperators**: Salinas, Tanimura and
Antle Corporation, and University of California. **Selected Refereed
Publications**: Boyd et al., 2005.

[]{#__RefHeading___Toc147540375 .anchor}**Modified crops for use in
organic production systems.** Crops sometimes need to be specifically
tailored for use in high-value organic systems. Conventional grain-type
soybeans fail to provide adequate crop residue to control soil erosion.
Therefore, a six-foot-tall, lodging-resistant soybean cultivar named
Tara was bred and released to farmers. Tara provided 72% more crop
residue after grain harvest than conventional cultivars, and is now
being used by farmers on several thousand acres. Moon Cake, a new dual
use vegetable soybean cultivar, was bred and released to farmers for
fresh green seeds to provide a vegetable protein for human consumption,
and for stover after seed harvested that can be fed to livestock. The
six-foot-tall Moon Cake enables it to compete against weeds. **ARS
Locations & Cooperators:** Beltsville. **Selected Refereed
Publications:** Devine et al., 2004.

[]{#__RefHeading___Toc147540376 .anchor}**Organic log-grown shiitake
mushrooms contain health-promoting polysaccharides.** There are two
major production systems for shiitake mushrooms. Log-grown shiitake
meets the standards for organic agriculture, but production costs are
greater than substrate-grown mushrooms. Customers may be more willing to
pay more for log-grown shiitakes if these mushrooms can be marketed as a
food that has health-promoting effects beyond its nutritional value.
Shiitakes are known to contain a polysaccharide that has been shown to
promote human health. Cooperative research by ARS scientists showed that
the content of this polysaccharide was at least twice as high in
log-grown shiitake, and both spawn source and tree species influenced
polysaccharide content. These results are of interest to shiitake
mushrooms growers interested in promoting their product to consumers of
healthy food products. This is a maturing accomplishment. Further
research is needed to fully characterize effects of management on health
promoting constituents. **ARS Locations & Cooperators:** Booneville,
Shirley Community Development Corporation. **Selected Refereed
Publications:** Brauer et al.., 2002

[]{#__RefHeading___Toc147540377 .anchor}**2. Integrating
agricultural-based energy production.** Crops specifically grown for
energy production and left over straw and manure from agricultural
operations are a part of the estimated 1.3-billion tons of biomass
available in the U.S. that could be used to produce energy. Research is
needed to incorporate small-scale thermal-chemical conversion
technologies that can be used to produce energy from biomass and manure
waste and directly generate additional revenue stream on the farm.

[]{#__RefHeading___Toc147540378 .anchor}**Sustainable production of
bio-fuel crops.** Experiments in eastern Washington demonstrated a
variety of oilseed crops could be grown as feedstocks for a biodiesel
industry, and ligno-cellulose reserves from wheat straw, corn stover,
and switchgrass could be utilized for ethanol production. Results
indicate that to support a 5-million gallon biodiesel facility, the land
area required ranges from 35-100,000 acres, depending on the oilseed
crop grown. Canola or rapeseed were determined to be the best crop
selections because of their high oil content, ability to fit into both
dryland and irrigated crop rotations, and that farmers currently
maintained the necessary agricultural equipment. Mustards, soybeans, and
safflower oilseeds could be used in rotations for crop diversification,
as well as oilseed markets. For ethanol production 30-60,000 acres of
switchgrass, wheat straw, or corn stover would be necessary to support a
20 million gallon ethanol facility. Twelve biodiesel and ethanol
facilities with annual production capacities of 30-M gallons biodiesel
and 290--M gallons of ethanol have been proposed for the Columbia Basin
of Washington and Oregon. This research is integral to estimate economic
thresholds for feedstock resources in the development of a sustainable
biofuels industry in the Columbia Basin. **ARS Locations and
Cooperators**: Prosser and Washington State University. **Selected
Refereed Publications:** none

[]{#__RefHeading___Toc147540379 .anchor}**Technology development for
farm--scale conversion of straw to energy.** Historically, much of the
straw produced from Pacific Northwest grass seed and cereal grain
cropping systems was treated as waste because of limited markets for
this excess residue. The high cost of transporting straw to centralized
conversion facilities has plagued previous value-added strategies. To
overcome this barrier, researchers evaluated the potential for the
on-farm conversion of straw to energy. A new gasifier designed
appropriately for on-farm use, was developed and tested utilizing
Kentucky bluegrass straw. The unit converted straw into synthesis gas
without slagging, a problem that has limited previous thermochemical
technologies. This successful proof of concept will be used to develop a
second-phase gasifier where the economic feasibility of converting straw
to energy can be evaluated on farm. Conversion of the excess 7-million
tons of straw beyond conservation requirement into liquid fuels could
yield more than 420-million gallons of mixed alcohol valued at
\$840-million. **ARS Locations & Cooperators:** Corvallis, Eastern
Regional Research Center, and Western Research Institute. **Selected
Refereed Publications:** Boateng et al., 2006. In press

[]{#__RefHeading___Toc147540380 .anchor}**3. New Products from
Agricultural Lands.** There are four accomplishments in this problem
area. Two are related to increased use and better management of
silvopastures for improving productivity and opening new market
alternatives. Another accomplishment examined the use of technology to
lengthen the growing season for high-valued crops and thus increase the
marketing season for producers in the region. The fourth accomplishment
increased the research capacity to identify constraints to increased
productivity and profitability in both conventional and organic systems.

[]{#__RefHeading___Toc147540381 .anchor}**Important criteria defined for
the design and management of temperate silvopasture practices.** More
than 20% of beef cattle in the U.S. (22.5 million head) are raised in
the lower Midwest United States. The region has more than 62.9 million
acres of private pasture that engages over 312,000 farm families. Equal
numbers of beef cattle are born or spend at least a portion of their
lives on pastures in the southeastern United States. Many family farms
also have significant acreages of wood lots, so adoption of silvopasture
has been advocated as a means to increase the productivity of these
resources. Understanding has been gained of how to design and manage
silvopastures to increase productivity and profitability. The
microclimate effect of pine trees in a silvopasture stimulates early
spring forage growth that allows livestock producers to place cattle on
pastures two-to-three weeks earlier than on open pasture. Similarly,
grazing in silvopastures can be extended two-to-three weeks later in the
fall. These results indicate that well-managed silvopastures can reduce
winter feed costs in the lower Midwest by approximately 20%.
Orchardgrass, or a binary mixture of orchardgrass and tall fescue, had
better growth, persistence, and feed quality than tall fescue in the
shade of loblolly pine alleys, while a tall fescue monoculture was more
productive in the unshaded environment. The spacing of loblolly trees on
a marginal site affected forage yield, nutritive value, and botanical
composition of a bermudagrass and tall fescue mixture within 7-8 years
after planting. Results from several different experiments indicate that
a two row configuration is optimum for timber production in southern
pine silvopasture, however, partitioning of biomass to the tree bole for
timber production may be less in agroforestry systems compared to
traditional forestry production systems. Economic analyses indicate that
the profitability of pecan silvopasture practices of the Midwest United
States is derived primarily from pecan nut sales. There are substantial
opportunities to increase the profitability of this practice by
marketing the timber from tree thinning. While nut yields of eastern
black walnut trees in a stand vary considerably, future yields can be
predicted. These results have added considerably to the knowledge of the
design and management of silvopastures. This knowledge needs to be
combined with forthcoming results for the development and dissemination
of site-specific best management practices for silvopastures. **ARS
Locations & Cooperators:** Booneville**,** Kansas State University,
University of Missouri-Columbia, Mississippi State University.
**Selected Refereed Publications:** Burner et al., 2003a. Burner et al.,
2003b. Burner et al., 2004. Ares et al., 2005. Ares et al., 2006.

[]{#__RefHeading___Toc147540382 .anchor}**Eastern red cedar and
chestnuts are attractive alternative crops for small farmers.** Crops
that are in high demand and command high prices are good alternative
crops for small farms. Chinese chestnut can begin bearing commercial
quantities of nuts 6-10 years after planting with 1,000-1,500 pounds of
nuts per acre easily attained. Current wholesale prices range from
\$1.60-6.00 per pound. In addition over 80% of current American supply
is from foreign markets, so this presents a ready domestic market. A
national market survey of eastern red cedar has shown that this species,
formerly viewed as a "trash" tree, has an expanding national market
valued in excess of \$60-million. These results indicate the potential
of increasing the profitability of small farms by the production of high
value alternative crops. **ARS Locations & Cooperators:** Booneville,
University of Missouri. **Selected Refereed Publications for this
Accomplishment: Selected Refereed Publications:** Gold et al., 2004.
Gold et al., 2005a. Gold et al., 2005b.

[]{#__RefHeading___Toc147540383 .anchor}**Cuphea as a new oilseed crop
for Northern Corn Belt.** Additional economically viable crops are
needed that can be grown in rotation with corn and soybeans to help
break weed and pest cycles and diversify farming operations. The U.S.A.
currently imports over a billion pounds of coconut and palm kernel oils
each year for use in making soaps, detergents, personal care products,
nutritional and dietetic products, and lubricants. Domesticated cuphea
could serve as a substitute for these and serve as a replacement for
certain high-value petroleum-based lubricants. Cuphea fits well in a
corn-soybean-wheat rotation following either soybean or wheat.
Additionally, corn yield may benefit when following cuphea. In 2004, in
collaboration with industrial partners, ARS scientists successfully took
cuphea to on-farm commercialization on 50 acres. In 2005, 100 acres were
grown, and over 400 acres have been contracted for 2006. Industrial
demand for cuphea oil is high enough that hundreds of thousands of acres
could be produced in the near future. **ARS Locations and Cooperators:**
Morris, Technology Crops International, Proctor and Gamble Company,
Minnesota Department of Agriculture, and Western Illinois University.
**Selected Refereed Publications:** Gesch et al., 2005. Forcella et al.,
2005. Forcella et al., 2005. Olness et al., 2005. Sharratt et al., 2004.

[]{#__RefHeading___Toc147540384 .anchor}**Small-Scale Farmers Can
Receive Income from Pine Straw Without Increasing Soil Erosion.** Pine
straw harvesting can provide an additional income source to small farms.
However, there are concerns that removal of pine straw will increase
soil erosion. Experiments conducted by the ARS Dale Bumpers Small Farms
Research Center, Booneville, Arkansas, showed how pine straw could be
harvested without increasing soil erosion. It was demonstrated that when
pine straw is harvested once every three years, precipitation run off,
soil erosion amount, and nutrient losses were not affected. This finding
benefits landowners looking for additional income sources as well as
conservation planners interested in helping these farmers. **ARS
Locations and Cooperators:** Booneville. **Selected Refereed
Publications:** none**.**

[]{#__RefHeading___Toc147540385 .anchor}**High tunnel research capacity
established to serve mid-Atlantic small farmers.** Small farmers near
urban areas successfully compete by targeted direct market strategies
that supply unique or superior quality products or optimize production
timing for high prices. Although high tunnels have been used in northern
areas for several years, mid-Atlantic growers have discovered tunnels
can provide advantages of extending the growing season and enhancing
product quality, despite the relatively mild climate in this region.
Houses with and without use of selective plastic that block the
transmission of solar ultraviolet radiation below 380 nm have been
established to determine how these optical properties impact crop and
pest management. Collaborative studies have demonstrated the enormous
potential of using high tunnels for production of high value crops that
can extend the growing season by 4-6 weeks in both the spring and the
fall. Results and recommendations are shared with other farmers through
field days and our winter regional conference with the expectation that
high tunnel use will rapidly expand throughout the area. **ARS Locations
& Cooperators:** Beltsville, Maryland Extension and SARE. **Selected
refereed publications:** Gonzalez-Aguilar et al., 2001. Krizek et al.,
2001. Krizek, et al., 2004. Krizek et al., 2005. Middleton et al., 2005.

# Research Goal III. Protected and Enhanced Natural Resources on Farms

Many landowners are recognizing the importance of describing the quality
of water and wildlife habitat associated with their farms. There are
several ARS units involved in natural resource research where
agricultural practices impact water ways and wildlife habitats. These
investigations provide a starting point to increase awareness of the
importance of wildlife resources in agriculture.

[]{#__RefHeading___Toc147540387 .anchor}**Use of remote sensing and
ground-truth surveys to monitor soil disturbance and land use patterns
across landscapes.** ARS scientists in Corvallis developed a combination
ground-truth survey and remote-sensing approach to create a public
geographic information system database of grass seed cropping practices
and stand establishment patterns in Linn County, Oregon. A multi-step
classification procedure using Landsat images to spatially and
temporally extend the database based on major land use categories
verified by a ground-truth census that showed the remote sensing method
to be 74% accurate. The GIS was used to characterize differences in soil
disturbance patterns among sub-basins of the Calapooia River watershed,
revealing the presence of a 3-fold range in proportion of agricultural
land tilled each year. Information on stand establishment and tillage
practices across the landscape is vital because our previous research
had demonstrated that tillage practices, rather than riparian buffers,
had greater impact on transport of sediments and nutrients in western
Oregon streams. Spatially-explicit quantification of soil disturbance
patterns will be a critical input to the Soil and Water Assessment Tool
model under development for landscape-level optimization of conservation
practices, crop production, water quality, and biological indicators of
ecosystem services. **ARS Locations & Cooperators**: Corvallis.
**Selected Refereed Publications**: none.

[]{#__RefHeading___Toc147540388 .anchor}**Identifying management
practices that optimize economic and environmental benefits at the
watershed scale level.** An integrated modeling system to provide
farmers, conservation planners, and policy makers a set of solutions
that optimize economic conservation practice selection was developed.
This accomplishment is important because the modeling system provides
documentation on the effectiveness of water quality conservation
practices supported by the Conservation Title in the USDA Farm Bill. A
working prototype, based on the results of replicated field trials, used
a genetic algorithm to integrate use of the ARS Soil and Water
Assessment Tool (SWAT) with an economic model. The system was applied to
a test watershed in western Oregon and will be used for the 13
watersheds in the national USDA *Conservation Effects Assessment
Project*. This research provides a new method to optimize multiple
conservation and economic objectives and is an important component of
assessment of USDA conservation programs at the national level. **ARS
Locations & Cooperators**: Corvallis, Temple, Oregon State University.
**Selected Refereed Publications:** Whittaker et al., 2003.

[]{#__RefHeading___Toc147540389 .anchor}**Wildlife habitat impacts
agricultural drainage water to constructed wetlands.** Do wetlands that
are constructed in rural landscapes to receive and treat agricultural
runoff and drainage water provide effective wildlife habitat? To answer
this question, this work studied the development of vascular vegetation
and periodically inventoried the terrestrial and aquatic ecology of
three constructed wetlands in Northwest Ohio receiving runoff and
drainage water from corn/soybean production systems. Hydrophytic
vegetation within the surrounding landscape provided an adequate source
of seed stock to achieve approximately 50 % wetland species in each
basin 5 years after construction without planting or seeding. Numbers
and types of both terrestrial and aquatic wildlife species increased
with time after construction at each wetland. Wetland site designers and
managers, NRCS, and Extension professionals, rural residents, and the
general public all benefited from these findings through evaluation of
current practice effectiveness, improved design and management
guidelines, and creation of additional wildlife habitat in the
agricultural landscape. **ARS Locations & Cooperators:** Columbus, Ohio
State University, and University of Findlay. **Selected Refereed
Publications:** Luckeydoo et al., 2002. Luckeydoo, 2004.

[]{#__RefHeading___Toc147540390 .anchor}**Importance of considering
environmental impacts of drainage ditch management.** Drainage ditches
are a common component of many agroecosystems in the eastern United
States. Historically, ditches have been managed for the single purpose
of draining excess water from agricultural fields without regard for the
ecological impacts these management actions. Research began in 2005 to
determine the influence of grassed buffers and farming practices on the
physical habitat and aquatic communities within agricultural drainage
ditches. Initial findings have documented that drainage ditches serve as
important habitats for fishes within agricultural watersheds, and
suggest that incorporation of environmental considerations into the
management of ditches will benefit the fishes within these systems.
Also, those conservation practices that alter ditch hydrological
characteristics will have the greatest impact on fishes and other
aquatic animals. This research will be valuable for state agencies,
federal agencies, and environmental groups responsible for funding and
assisting producers with installing grassed buffers, implementing
nutrient management practices, and implementing pesticide management
practices through USDA Farm Bill programs. The results will also provide
producers information to consider to manage ditches as multi-purpose
systems designed to provide habitat for aquatic animals and drainage of
agricultural fields. **ARS Locations & Cooperators:** Columbus, Ohio
State University, Purdue University, Upper Big Walnut Creek Water
Quality CEAP-SWPI, Ohio Department of Natural Resources, and Rural
Drainage Ditch Advisory Committee. **Selected Refereed Publications:**
none.

[]{#__RefHeading___Toc147540391 .anchor}**Grass seed farming landscapes
provide excellent fish and wildlife habitat.** Farm aquatic and
terrestrial habitats protect many fish and wildlife species, and thus
serve as a valuable resource worthy of enhancement and protection. It
was found that native fish and amphibians utilized seasonal streams,
originating from western Oregon grass seed fields, as refugia during the
winter high flow periods. Water quality nutrient constituents were found
to be at ranges not harmful to aquatic biota. Winter bird abundance and
diversity was correlated with the percent of tree cover along drainages
in the south Willamette River basin, OR. Surveys demonstrated that
seventeen-times more birds were found along forested than non-forested
drainages, but only 15% of the total land cover needed to be in trees to
maximize songbird richness. Using bird behavior findings and knowing
that 70% of the watershed land area is less than optimal, farmers can
now know where to target USDA conservation projects to optimize economic
and environmental benefits. These studies provide the first-of-its-kind
comprehensive information showing how managed upland agricultural
landscapes in watersheds are places where species listed under the
Endangered Species Act can flourish during seed production cycles. **ARS
Locations & Cooperators:** Corvallis, Oregon State University,
University of Massachusetts, USDA-NRCS, and local farmers. **Selected
Refereed Publications:**

McComb et al., 2005. Banowetz et al., 2006.

[]{#__RefHeading___Toc147540392 .anchor}**Management schemes for alley
cropping practices improve dove habitat.** There are substantial
opportunities at the rural-urban interface for farmers to increase their
profitability by managing their landscape for game species and charging
fees for hunting access. Mast-bearing trees alley cropped with
sunflowers is an attractive management option to farmers interested in
dove lease-hunting. Missouri has 40,000 dove hunters who spend
\$5-million annually, and demand is increasing. Components important to
development of management protocols for enhancing dove habitat are being
investigated. Swamp white oak seedlings produced from acorns in large
containers will bear acorns within 18-30 months, in contrast to 15-30
years for natural oak stands. Effective and substantial weed control was
found to be critical to establishment of hardwood plantations,
especially in the floodplains of major rivers. Establishing oak
seedlings in former bottomland crop fields with a cover crop of redtop
grass will prevent rabbit damage and produce 98% survival four years
after outplanting. The spring growth and short stature of the redtop
grass prevents the growth of other competitive understory vegetation and
is a poor habitat for rabbits. These results provide a framework for
successful alley cropping practices to establish oak seedlings to
increase dove habitat and increase farm profitability via hunting lease
fees. These results need to be transferred to landowners to increase
adoption of such practices in the Midwest region of the United States.
This accomplishment has focused primarily on system components to date.
Additional component research is needed, including system level
analyses. Future technology transfer activities will be required for the
research to have full impact. **ARS Locations & Cooperators:**
Booneville, Missouri landowners, U.S. Forest Service, NRCS, and
University of Missouri. **Selected Refereed Publications:** Grossman et
al., 2003. Ares and Brauer, 2004. Kabrick et al., 2005.

# Peer Review Publications

1.  Abdul-Baki, A., Bryan, H.H. Klassen, W. and Codallo, M. Propagation
    and establishment of perennial peanuts for ground covers along
    roadsides and highway ramps. Proc. Fla. State Hort. Soc.
    115:267-272. 2002.

2.  Abdul-Baki, A., Bryan, H.H. Klassen, W. Carrera, L. Li, Y.C. and
    Wang, Q. Low production cost alternative systems are the avenue for
    future sustainability of vegetable growers in the U.S. Acta
    Horticulturae 638: 419-423. 2004.

3.  Abdul-Baki, A., Bryan, H.H., Klassen, W., and Codallo, M.
    Propagation and establishment of perennial peanuts for ground covers
    along roadsides and highway ramps. Proc. Fla. State Hort. Soc. 115:
    267-272. 2002.

4.  Abdul-Baki, A., Bryan, H.H., Klassen, W., Carrera, L., Li, Y.C., and
    Wang, Q. Low production cost alternative systems are the avenue for
    future sustainability of vegetable growers in the U.S. Acta
    Horticulturae 638: 419-423. 2004.

5.  Abdul-Baki, A., H.H. Bryan, W. Klassen, and M. Codallo. Propagation
    and establishment of perennial peanuts for ground covers along
    roadsides and highway ramps. Proc. Fla. State Hort. Soc.
    115:267-272. 2002.

6.  Abdul-Baki, A., H.H. Bryan, W. Klassen, L. Carrera, Y.C. Li, and Q.
    Wang. Low production cost alternative systems are the avenue for
    future sustainability of vegetable growers in the U.S. Acta
    Horticulturae 638: 419-423. 2004.

7.  Abdul-Baki, A., Wilson, A. Carrera, L. M. Aslan, S. Cobb, S.
    Burke, T. and Brown Jr., E. Browning and dieback of distal parts of
    fruit-bearing strands in date palms. HortScience 37:882-884. 2002.

8.  Abdul-Baki, A., Wilson, A. Carrera, L.M. Aslan, S. Cobb, S.
    Burke, T. and Brown Jr., E. Browning and dieback of distal parts of
    fruit-bearing strands in date palms. HortScience 37:882-884. 2002.

9.  Abrahamson D.A., Radcliffe D.E., Steiner J.L., Cabrera M.L., Hanson
    J.D., Rojas K.W., Schomberg H.H., Fisher D.S., Schwartz L.,
    Hoogenboom G. Calibration of the root zone water quality model for
    simulating tile drainage and leached nitrate in the Georgia
    Piedmont. Agronomy Journal 97: 1584-1602. 2005.

10. Aiken, R., Nielsen, D.C., and Ahuja, L.R. Scaling effects of
    standing crop residues on the wind profile. Agronomy J.
    95:1041-1046. 2003.

11. Ali, I., F.D. Whisler, J. Iqbal, J.N. Jenkins. Soil physical
    properties web database for GOSSYM and GLYCIM crop simulation
    models. Agronomy J. 96:1706-1710. 2004.

12. Alva, A.K. Effects of pre-plant and in-season nitrogen management
    practices on tuber yield and quality of two potato cultivars.
    Journal of Vegetable Crop Production. 2004. 10:43-60.

13. Alva, A.K. Potato nitrogen management. Journal of Vegetable Crop
    Production. 10:97-132. 2004.

14. Alva, A.K. Sustainable nutrient management in sandy soils-Fate and
    transport of nutrients from animal manure vs. inorganic sources. J.
    Sustainable Agric. (In press) 2006.

15. Alva, A.K., Collins, H.P., Fraisse, C., Boydston, R.A. Evaluation of
    Enviroscan capacitance probes for monitoring soil moisture in center
    pivot irrigated potatoes. Journal of Applied Irrigation Science,
    38:93-110. 2003.

16. Alva, A.K., H.P. Collins, and R.A. Boydston. Corn, wheat, and potato
    crop residue decomposition and nitrogen mineralization in sandy
    soils under an irrigated potato rotation. Comm. Soil Sci and Plant
    Anal. 33:2643-2651. 2002.

17. Alva, A.K., H.P. Collins, W.L. Boge, and R.A. Boydston. In-situ
    measurement of nitrogen mineralization from different crop residues
    in the Pacific Northwest irrigated potato cropping systems. J. Veg.
    Crop Improvement. (In press). 2006.

18. Alva, A.K., Paramasivam, S., Fares, A., Delgado, J.A., Mattos, D.,
    Sajwan, K. Nitrogen and irrigation management practices to improve
    nitrogen uptake efficiency and minimize leaching losses. Journal of
    Crop Improvement 15:369-420. 2005.

19. Alva, A.K., S. Paramasivam, and K.S. Sajwan. Nitrogen transformation
    from three organic amendments in a sandy soil. Archives Agron. Soil
    Sci 52:1-11. 2006.

20. Alva, A.K., T. Hodges, R.A. Boydston, and H.P. Collins. Dry matter
    and nitrogen accumulation and partitioning in two potato
    cultivars. J. of Plant Nutr. 25:1621-1630. 2002.

21. Alva, A.K., T. Hodges, R.A. Boydston, and H.P. Collins. Effects of
    irrigation and tillage practices on yield of potato under high
    production conditions in the Pacific Northwest. Comm. Soil Sci and
    Plant Anal. 33:1451-1460. 2002.

22. Anbumozhi, V., V. R. Reddy, Yao-Chi Lu, and E. Yamaji. The role of
    crop simulation models in agricultural research and development.
    Agricultural Engineering Journal 12:1 - 18. 2003

23. Andales, A.A., Ahuja, L.R., and Peterson, G.A. Evaluation of GPFARM
    for dryland cropping systems in Eastern Colorado. Agronomy J. 95:
    1510-1524. 2003.

24. Andales, A.A., Derner, J.D., Bartling, P.N.S., Ahuja, L.R., Dunn,
    G.H., Hart, R.H., and Hanson, J.D. Evaluation of GPFARM for
    simulation production and cow-calf weights. Rangeland Ecology and
    Management. 58:247-255. 2005. 

25. Archer, D. W., Pikul, J. L., Jr. and Riedell, W. E. Economic risk,
    returns and input use under ridge and conventional tillage in the
    northern Corn Belt, USA. Soil and Tillage Research 67(1):1-8. 2002.

26. Archer, D.W., Pikul, J. L., Jr., and Riedell, W. E. Analyzing risk
    and risk management in cropping systems. *In:* Hanson, J.D. and J.M.
    Krupinsky (eds.), Proceedings of the Dynamic Cropping Systems:
    Principles, Processes, and Challenges. Bismarck, ND. p.155-164.
    2003.

27. Ares, A. and Brauer, D. Growth and nut production in black walnut in
    relation to site, tree type and stand conditions in the south
    central United States. Agroforestry Systems 63:83-90. 2004.

28. Ares, A. and D. Brauer. Aboveground Biomass Partitioning in Loblolly
    Pine Silvopastoral Stands: Spatial Configuration and Pruning
    Effects. Forest Ecology and Management. 219:176-184. 2005**.**

29. Ares, A., D. and D. Brauer**.** 2003. Trends in tree growth and
    understory yield in

30. Ares, W.C. Reid and D. Brauer. Production and economics of native
    pecan silvopastures in central United States. Agroforestry Systems:
    66: 205-215. 2006.

31. Ascough II, J.C., Hoag, D.L., McMaster, G.S., and Frasier, W.M.
    Computer use and satisfaction by Great Plains producers: Ordered
    logit model analysis. Agron. J. 94:1263-1269. 2002.

32. Ashford, D.L., and D.W. Reeves. 2003. Use of a mechanical
    roller-crimper as an alternative kill method for cover crops.
    American Journal of Alternative Agriculture 18(1):37-45.

33. Avery, A. 2005. Organic and conventional agriculture reconsidered.
    Letter to the editor, BioScience 55:820.

34. Bakhsh, A., Hatfield, J.L., Kanwar, R.S., Ma, L., and Ahuja, L.R.
    Simulating nitrate losses from Walnut Creek Watershed. J. Environ.
    Quality. 33:114-123. 2004.

35. Bakhsh, A., Kanwar, R.S., Jaynes, D.B., Colvin, T.S., and Ahuja,
    L.R. Simulating effects of variable nitrogen application rates on
    yield and NO~3~-N losses in subsurface drain water. Trans. ASAE
    44(2): 269-276. 2001.

36. Bakhsh, A., Ma, L., Ahuja, L. R., Hatfield, J.L., and Kanwar, R.S.
    Using RZWQM to predict herbicide leaching losses in subsurface
    drainage water. Trans. ASAE. 47:1415-1426. 2004.

37. Balkcom, K.S., J.A. Terra, J.N. Shaw, D.W. Reeves, and R.L.
    Raper. 2005. Soil management system and landscape position
    interactions on nutrient distribution in a Coastal Plain field. J.
    Soil Water Conser. 60(6): 431-437.

38. Banowetz, G.M., Azevedo, M.D., Kennedy, A.C., Griffith, S. M. and
    Steiner, J. J. Fatty acid methyl ester analysis (FAME) to identify
    sources of soil in surface water J. Environ. Qual. 35: 133-140.
    2006.

39. Bauer, P. J., J. R. Frederick, and W. J. Busscher. 2002. Tillage
    effect on nutrient stratification in narrow- and wide-row cropping
    systems. Soil & Tillage Res. 66:175-182.

40. Bauer, P.J. and M.E. Roof. 2004. Nitrogen, Aldicarb, and Cover Crop
    Effects on Cotton Yield and Fiber Properties. Agron. J. 96:369-376.

41. Bauer, P.J., C.R. Camp and W.J. Busscher. 2002. Conservation tillage
    methods for cotton grown with subsurface drip irrigation on
    compacted soil. Trans. ASAE 45(1):119-125.

42. Bauer, P.J., D.W. Reeves, R.M. Johnson and J.M. Bradow. 2003. Cover
    crop, tillage, and N rate effect on cotton grown in ultra-narrow
    rows. Crop Management dol:10.1094/CM-2003-1006-01-RS.

43. Bauer, P.J.and J.R. Frederick. 2005. Tillage Effects on Canopy
    Position Specific Cotton Fiber Properties on Two Soils. Crop Sci.
    45:698--703.

44. Bauerle, W.L., D. J. Timlin, Ya. Pachepsky, and S. Anantharamu.
    Adaptation of the Biological Simulation Model MAESTRA for Use in a
    Generic User Interface Agron. J. 98: 220-228. 2005

45. Number range CHAPTERBirrell, S.J. and Hummel, J.W. Real-time multi
    ISFET/FIA soil analysis system with automatic sample extraction.
    Comp. Elect. Agric. 32(1):45-67. 2001.

46. Boateng, A. A., G.M. Banowetz, G. M., Steiner, J. J., Barton, T. F.,
    Taylor, D. G., Hicks, K. B., El-Nashaar, H. and Sethi. V. K.
    Gasification of Kentucky bluegrass (*Poa pratensis* L.) straw in a
    farm-scale reactor. Biomass and Bioenergy (in press).

47. Brauer, D., A. Ares, W. Reid, A. Thomas and J.P. Slusher. 2006.
    Nut-yield variations and yield-DBH relationships in open-canopy
    black walnuts in southern USA. Agroforestry Systems 67:63-72.

48. Brauer, D., Kimmons, T., and Phillips, M. 2002. Effects of
    management on the yield and high molecular weight polysaccharide
    content of shiitake (*Lentinula edodoes*) mushrooms. Journal of
    Agricultural and Food Chemistry 50:5333-5337.

49. Brennan, E.B. and R.F. Smith. 2005. Winter cover crop growth and
    weed suppression on the central coast of California. Weed Technology
    19:1017-1024. Kaspar, T.C., J.K. Radke, and J.M. Laflen. 2001. Small
    grain cover crops and wheel traffic effects on infiltration, runoff,
    and erosion. J. Soil Water Conserv. 56(2):160-164.

50. Brevik, E.C., T.E. Fenton, and D.B. Jaynes. Evaluation of the
    accuracy of a central Iowa soil survey and implications for
    precision soil management. Precision Agriculture. 4:331-342.

51. Brewer, M. T., and Larkin, R. P. Efficacy of several potential
    biocontrol organisms against *Rhizoctonia solani* on potato. Crop
    Protection 24:939-950. 2005.

52. Bryson, C.T. and Hanks, J.E. 2004. Weed Populations as Related to
    Conservation Tillage and Reduced Herbicide Management Systems:
    Mississippi Delta Management Systems Evaluation Area, pp. 204-217.
    In: Nett, M.T., Locke, M.A., and Pennington, D.A. (eds.) Water
    Quality Assessments in the Mississippi Delta: Regional Solutions,
    National Scope, American Chemical Society Symposium Series 877. New
    York, NY: Oxford University Press. 284 pp.

53. Bryson, C.T. and Hanks, J.E. 2001. Weed shifts in Deep Hollow
    watershed, Leflore County, MS, pp 86-90. In Rebich, R.A. and
    Knight, S. (eds.) The Mississippi Delta Management Systems
    Evaluation Areas Project, 1995-99. Mississippi Agricultural &
    Forestry Experiment Station Information Bulletin 377. 222 pp.

54. Bull, C. T. 2006. US Federal Organic Research Activity Is Expanding.
    Crop Management (submitted November 2005).

55. Bull, C. T., Muramoto, J., Koike, S. T., Leap, J., Shennan, C., and
    Goldman, P. 2004. Evaluation of strawberry cultivars and mycorrhizal
    inoculants in California organic production fields. (Online) Crop
    Management doi:10.1094/CM-2005-0527-02-RS.

56. Burke J.M., and Miller, J.E. Evaluation of multiple low dose copper
    oxide wire particles compared with levamisole for control of
    *Haemonchus contortus* in lambs. Veterinary Parasitology (Available
    Online as of April 1, 2006). 2006.

57. Burke J.M., and Miller, J.E. Relative resistance of Dorper crossbred
    ewes to gastrointestinal nematode infection compared with St. Croix
    and Katahdin ewes in the southeastern United States. Veterinary
    Parasitology 109:265-275. 2002.

58. Burke J.M., and Miller, J.E. Relative resistance to gastrointestinal
    nematode parasites in Dorper, Katahdin, and St. Croix lambs under
    conditions encountered in the southeastern region of the United
    States. Small Ruminant Research 54:43-51. 2004.

59. Burner, D.M. Influence of alley crop environment on orchardgrass and
    tall fescue herbage. Agron. J. 95:1163-1171. 2003.

60. Burner, D.M. and D.K. Brauer. Herbage response to spacing of
    loblolly pine trees in a minimal management silvopasture in
    southeastern USA. Agrofor. Syst. 57:69-77. 2003.

61. Burner, D.M. and D.P. Belesky. Diurnal effects on nutritive value of
    alley-cropped orchardgrass herbage. Crop Sci. 44:1776-1780. 2004.

62. Burns, J.C., Mayland, H.F., and Fisher, D.S. Dry matter intake and
    digestion of alfalfa harvested at sunset and sunrise. J. Animal Sci.
    83:262-270. 2005.

63. Busscher, W. J., P. J. Bauer, and J. R. Frederick. 2002.
    Recompaction of a coastal loamy sand after deep tillage as a
    function of subsequent cumulative rainfall. Soil & Tillage Res.
    68(1):49-57.

64. Butler, J.L., Bottomley, P.J., Griffith, S. M. and Myrold, D. D.
    Distribution and turnover of recently fixed photosynthate in
    ryegrass rhizospheres. Soil Biology & Biochemistry 36: 371-382.
    2004.

65. Butts, C.L., Davidson, J.I., Jr., Lamb, M.C., Kandala, C.V., and
    Troeger, J.M. Estimating Drying Time for a Farmer Stock Peanut
    Curing Decision Support System. Trans. of ASAE. 47(3): 925-932.
    2004.

66. Caesar‑TonThat, T. C. 2002. Soil binding properties of mucilage
    produced by a basidiomycete fungus in a model system. Mycological
    Res. 106:930‑937.

67. Caesar‑TonThat, T. C., W. Shelver, R.G. Thorn, and V.L.
    Cochran. 2001. Generation of antibodies for soil‑aggregating
    basidiomycete detection to determine soil quality. Appl. Soil Ecol.
    18:99‑116.

68. Caesar-TonThat, T.C. and V. Cochran. 2002. Role of saprophytic
    basidiomycete soil fungus I aggregate stability. pg. 575-579 *In*
    D.E. Stott, RH. Hohtar, and G.C. Steinhardt (eds.). Sustaining the
    Global Farm -- Selected papers from the 10^th^ International Soil
    Conference Organization Meeting, May 23-28, 1999, West Lafayette,
    IN. (Refereed proceeding).

69. Caesar-TonThat, T.C. and V.L. Cochran. 2001. Role of saprophytic
    basidiomycete soil fungus in aggregate stabilization pg 580-587
    *In*: D.E. Stott, RH. Hohtar, and G.C. Steinhardt (eds.). Sustaining
    the Global Farm -- Selected papers from the 10^th^ International
    Soil Conference Organization Meeting, May 23-28, 1999, West
    Lafayette, IN. (Refereed proceeding).

70. Caesar-TonThat, T.C. 2002. Soil binding properties of mucilage
    produced by a basidiomycete fungus I a model system. Mycological
    Res. 106:930-937.

71. Caesar-TonThat, T.C., Shelver, W.L., Thorn, R.G., and Cochran, V.L.
    Generation of antibodies for soil-aggregating basidiomycete
    detection to determine soil quality. Appl. Soil Ecol. 18:99-116.
    2001.

72. Cambell, C.A., Janzen, H.H., Paustian, K., Gregorich, G., Sherrod,
    L., Liang, B.C., and Zentner, R.P. Carbon storage in soils of the
    North American Great Plains: effect of cropping frequency.
    Agronomy J. 97:1-15. 2005. 

73. Cameira, M.R., Fernando, R.M., Ahuja, L.R. and Pereira, L.
    Simulating the fate of water in field soil-crop environment. J.
    Hydrology. 315:1-24. 2005.

74. Canner, S.R., L.J. Wiles, and G.S. McMaster. 2002. Weed reproduction
    model parameters may be estimated from crop yield loss data. Weed
    Science 50:763-772.

75. Cavigelli, M.A., L.L. Lengnick, J.S. Buyer, D. Fravel, Z. Handoo, G.
    McCarty, P. Millner, L. Sikora, S. Wright, B. Vinyard, and M.
    Rabenhorst. Landscape level variation in soil resources and
    microbial properties in a no-till corn field. Applied Soil Ecology
    29:99-123. 2005.

76. Chander, S., L. R. Ahuja, F. B. Peairs, P. K. Aggarwal, and N.
    Kalra. 2006. Modeling the effect of Russian wheat aphid, Diuraphis
    noxia (Mordvilko) and weeds in winter wheat as guide to management.
    Agric. Systems. 88:494-513.

77. Chaoui, H.I., Zibilske, L.M. and Ohno, T. Effects of earthworm casts
    and compost on soil microbial activity and plant nutrient
    availability. Soil Biology & Biochemistry 35:295-302. 2003.

78. Chung, S.O. and Sudduth, K.A. 2004Characterization of cone index and
    tillage draft data to define design parameters for an on-the-go soil
    strength profile sensor. Agric. Biosystems Eng. 5(1):10-20..

79. Chung, S.O. and Sudduth, K.A. 2005. On-the-go soil strength profile
    sensor to quantify spatial and vertical variations in soil strength.
    Agric. Biosystems Eng. 6(2): 39-46.

80. Chung, S.O., Sudduth, K.A., and Chang, Y.C. 2005. Path analysis of
    factors limiting crop yield in rice paddy and upland corn fields. J.
    Biosystems Eng. 30(1):45-55.

81. Number range CHAPTERChung, S.O., Sudduth, K.A., and Drummond,
    S.T. 2002. Determining yield monitoring system delay time with
    geostatistical and data segmentation approaches. Trans. ASAE
    45(4):915-926.

82. Chung, S.O., Sudduth, K.A., and Hummel, J.W. 2006. Design and
    validation of an on-the-go soil strength profile sensor. Trans.
    ASABE 49(1):5-14.

83. Clement, S.L., L.R. Elberson, F.L Young, J.R. Alldredge, R.H.
    Ratcliffe, and C. Hennings. Variable *Hessian* fly (*Diptera:
    Cedidomyiidae*) populations in cereal production systems in eastern
    Washington. J. Kansas Entomol. Soc 76: 567-577. 2003.

84. Clement, S.L., L.R. Elberson, N. Youssef, F.L. Young, and M.A.
    Evans. Cereal aphid and natural enemy populations in cereal
    production systems in eastern Washington. J. Kansas Entomol. Soc.
    77(3):165-173. 2004.

85. Clancy, S. and Jacobson, B. 2006. A new conservation education
    delivery system. Renewable Agriculture and Food Systems. (in-press)

86. Clay, D.E., Kitchen, N.R., Carlson, C.G., Kleinjan, J.L, and
    Tjentland, W.A. Collecting representative soil samples for N and P
    fertilizer recommendations. Online. Crop Management
    doi:10.1094/CM-2002-1216-01-MA. 2002.

87. Dadson, R.B., Hashem, F.M., Javaid, I., Joshi, J.M., Allen, A.L.,
    and Devine, T.E**.** 2004. Effects of water stress on the yield of
    cowpea (*Vigna unguiculata* L. Walp.) genotypes in the Delmarva
    region of the United States. J. of Agronomy and Crop Sci. 190:1-8.

88. Darmosarkoro, W., Harbut, M.M., Buxton, D.R., Moore, K.J., Devine,
    T.E**.** and Anderson, I.C. Growth, development, and yield of
    soybean lines developed for forage. Agronomy J. 93:1028-1043. 2001.

89. Davenport, J.R., C.A. Redulla, M.J. Hattendorf, R.G. Evans and R.A.
    Boydston. 2002. Potato Yield Monitoring on Commercial Fields.
    HortTechnology. April-June 12(2):289-296.

90. Davidson, J.I., Jr., McGill, F., Moss, R., Butts, C.L., Lamb, M.C.
    and Sternitzke, D.A. "HarvPro 1.0", an expert systems user's guide.
    Released via CRADA with the Peanut Foundation, 2002. (Technical
    Bulletin)

91. Davidson, J.I., Sternitzke, D.A., Lamb, M.C., McGill, F., Moss, R.,
    and Williams, E.J. A Knowledge Base for Dryland Pro, An Expert
    System for Managing Non-irrigated Peanut Production. Computer
    Software: Decision Support System. 2002. (Technical Bulletin)

92. Davis, J.M., Griffith, S. M., Horwath, W. R., Steiner, J. J. and
    Myrold, D. D. Fate of ^15^N-labeled ammonium and nitrate in a
    perennial ryegrass seed field and grass riparian zone. Soil Sci.
    Soc. Am. (in press)

93. Delate, K. and C. Cambardella. 2004. Agroecosystem performance
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     conductivity to claypan soil properties. Soil Sci. Soc. Am. J.
     69:883-892. 2005.

200. Kabrick, J.M., Dey, D.C., Van Sambeek, J.W., Wallendorf, M., and
     Gold, M. Soil mounding effects on regenerating oaks in Missouri
     River floodplains. Forest Ecology and Management 204: 315-327.
     2005.

201. Kallenbach, R.L., G.J. Bishop-Hurley, M.D. Massie and C.A.
     Roberts. 2002. Stockpiled annual

202. Kaspar, T.C., D.J. Pulido, T.E. Fenton, T.S. Colvin, D.L. Karlen,
     D.B. Jaynes, and D.W. Meek. Relationship of corn and soybean yield
     to soil and terrain properties. Agron. J. 96:700-709. 2004.

203. Kaspar, T.C., J.K. Radke, and J.M. Laflen. 2001. Small grain cover
     crops and wheel traffic effects on infiltration, runoff, and
     erosion. J. Soil Water Conserv. 56(2):160-164.

204. Kaspar, T.C., T.S. Colvin, D.B. Jaynes, D.L. Karlen, D.E. James,
     and D.W.Meek. Relationship between six years of corn yields and
     terrain attributes. Precision Agriculture. 4:87-101. 2003.

205. Kim, H., Hummel, J.W., and S.J. Birrell. Evaluation of nitrate and
     potassium ion-selective membranes for soil macronutrient sensing.
     Trans. ASABE 49. In press. 2006.

206. Kitchen, N.R., Drummond, S.T., Lund, E.D., Sudduth, K.A., and
     Buchleiter, G.W. Soil electrical conductivity and other soil and
     landscape properties related to yield for three contrasting soil
     and crop systems. Agron. J. 95:483-495. 2003.

207. Kitchen, N.R., Sudduth, K.A., Myers, D.B., Drummond, S.T., and
     Hong, S.Y. Delineating productivity zones on claypan soil fields
     using apparent soil electrical conductivity. Comp. Elect. Agric.
     46:285-308. 2005.

208. Kitchen, N.R., Sudduth, K.A., Myers, D.B., Massey, R.E., Sadler,
     E.J., Lerch, R.N., Hummel, J.W., and Palm, H.L. Development of a
     conservation-oriented precision agriculture system: Crop production
     assessment and plan implementation. J. Soil Water Conserv.
     60(6):421-430. 2005.

209. Koivisto, J.M., Devine, T.E. Lane, G.P.F., Sawyer, C.A., Brown,
     H.J. Forage soybeans (*Glycine max* (L.) Merr.) in the United
     Kingdom: Test of new cultivars. Agronomie 23:287-291. 2003.

210. Koti, S., K. R. Reddy, V. G. Kakani, D. Zhao**,** V. R. Reddy.
     Soybean (Glycine max) Pollen Germination Characteristics, Flower
     and Pollen Morphology in Response to Enhanced Ultraviolet-B
     Radiation. Annals of Botany 94:855-864. 2004

211. Kozak, J. A. and Ahuja, L.R. Scaling of infiltration and
     redistribution across soil textural classes. Soil Sci. Soc. Am. J.
     69:816-827. 2005.

212. Kozak, J., Ahuja, L.R., Ma, L., and Green, T.R. Scaling and
     estimation of evaporation and transpiration of water across soil
     texture classes. Vadose Zone J. 4:418-427. 2005.

213. Krizek, D.T. Influence of PAR and UV-A in determining plant
     sensitivity and photomorphogenic responses to UV-B radiation.
     Photochemistry and Photobiology 79(4):307-315. 2004.

214. Krizek, D.T. Influence of PAR and UV-A in determining plant
     sensitivity and

215. Krizek, D.T., Chalker-Scott, L. 2005. Symposium-in-Print.
     Introduction. Ultraviolet and terrestrial ecosystems.
     Photochemistry and Photobiology 81(5):1021-1025.

216. Krizek, D.T., Middleton, E.W., Sandhu, R.K., and Kim, M.S.
     Evaluating UV-B effects and EDU protection in cucumber leaves using
     fluorescence images and fluorescence emission spectra. Journal of
     Plant Physiol. 158:41-53. 2001.

217. Krupinsky, J.M., Tanaka, D.L., Merrill, S.D., Liebig, M.A., and
     Hanson, J.D. Crop sequence effects of ten crops in the Northern
     Great Plains. Agric. Systems 88:227-254. 2006.

218. Kumar, V., Mills, D.J., Anderson, J.D., and Mattoo, A.K. 2004. An
     alternative agriculture system is defined by a distinct expression
     profile of select gene transcripts and proteins. Proc. Natl. Acad.
     Sci. USA. 101:10535-10540.

219. Kumar, V., Mills, D.J., Anderson, J.D., and Mattoo, A.K. 2004.
     Delayed senescence and disease tolerance of tomato plants
     cultivated in cover crop mulch correlates with accumulation of
     specific gene products. Acta Horticulturae 638:497-502.

220. Lamb, M.C., Masters, M.H., Rowland, D., Sorensen, R.B., Zhu, H.,
     Blankenship, P.D. and Butts, C.L. 2005. Impact of Sprinkler
     Irrigation Amount and Rotation On Peanut Yield. Peanut Sci.
     31:108-113.

221. Larkin, R. P. Characterization of soil microbial communities under
     different potato cropping systems in central Maine by microbial
     population dynamics, substrate utilization, and fatty acid
     profiles. Soil Biol. Biochem. 35:1451-1466. 2003.

222. Larkin, R. P. Effect of green sprouting and biocontrol products on
     soilborne diseases of potato, 2002. Biological and Cultural Tests
     for Control of Plant Diseases (Online) Report 18:PT011.
     DOI:10.1094/ BC18. 2003.

223. Larkin, R. P. Effects of crop rotations and a fall cover crop on
     Rhizoctonia canker, black scurf, and common scab of potato, 2004.
     Biological and Cultural Tests for Control of Plant Diseases
     (Online) Report 21:V009. DOI:10.1094/ BC21. 2006.

224. Larkin, R. P. Effects of different 3-yr cropping systems on
     Rhizoctonia canker and black scurf of potato in northern Maine,
     2000 and 2001. Biological and Cultural Tests for Control of Plant
     Diseases (Online) Report 17:PT05. DOI:10.1094/ BC17. 2002.

225. Larkin, R. P., and Fravel, D. R. Effects of varying environmental
     conditions on biological control of Fusarium wilt of tomato by
     nonpathogenic *Fusarium* spp. Phytopathology 92:1160-1166. 2002.

226. Larkin, R. P., and Groves, C. L. Identification and
     characterization of isolates of *Phytophthora infestans* using
     fatty acid methyl ester (FAME) profiles. Plant Dis. 87:1233-1243.
     2003.

227. Larkin, R. P., and Honeycutt, C. W. Crop Rotation effects on
     Rhizoctonia canker and black scurf of potato in central Maine, 1999
     and 2000. Biological and Cultural Tests for Control of Plant
     Diseases (Online) Report 17: PT06. DOI:10.1094/ BC17. 2002.

228. Larkin, R. P., and Honeycutt, C.W. Effects of different 3-year
     cropping systems on soil microbial communities and Rhizoctonia
     disease of potato. Phytopathology 96: 68-79. 2006.

229. Larkin, R.P. Characterization of soil microbial communities under
     different potato cropping systems in central Maine by microbial
     population dynamics, substrate utilization, and fatty acid
     profiles. Soil Biol. Biochem. 35:1451-1466. 2003.

230. Larkin, R.P. Control of Rhizoctonia canker and black scurf of
     potato by biological products, 2001. Biological and Cultural Tests
     for Control of Plant Diseases (Online) Report 17: PT05.
     DOI:10.1094/ BC17. 2002.

231. Larkin, R.P. Control of Rhizoctonia stem canker and black scurf of
     potato by biological products. Biological and Cultural Tests for
     Control of Plant Diseases (Online) Report 16:PT70. DOI:10.1094/
     BC16. 2001.

232. Larkin, R.P. Effect of green sprouting and biocontrol products on
     soilborne diseases of potato, 2002. Biological and Cultural Tests
     for Control of Plant Diseases (Online) Report 18:PT011.
     DOI:10.1094/ BC18. 2003.

233. Larkin, R.P. Effects of crop rotations and a fall cover crop on
     Rhizoctonia canker, black scurf, and common scab of potato, 2004.
     Biological and Cultural Tests for Control of Plant Diseases
     (Online) Report 21:V009. DOI:10.1094/ BC21. 2006.

234. Larkin, R.P. Effects of different 3-yr cropping systems on
     Rhizoctonia canker and black scurf of potato in northern Maine,
     2000 and 2001. Biological and Cultural Tests for Control of Plant
     Diseases (Online) Report 17:PT05. DOI:10.1094/ BC17. 2002.

235. Larkin, R.P., and Groves, C.L. Identification and characterization
     of isolates of *Phytophthora infestans* using fatty acid methyl
     ester (FAME) profiles. Plant Dis. 87:1233-1243. 2003.

236. Larkin, R.P., and Honeycutt, C.W. Effects of different 3-year
     cropping systems on soil microbial communities and Rhizoctonia
     disease of potato. Phytopathology 96: 68-79. 2006.

237. Larkin, R.P., Honeycutt, C.W., and Griffin, T.S. Effect of swine
     and dairy manure amendments on microbial communities in three soils
     as influenced by environmental conditions. Biol Fertil. Soils:
     (Published Online 10/20/05; DOI:10.1007/s00374-005-0060-7). 2006.

238. Lartey, R. T., Weiland, J. J., Caesar-TonThat, T. C., and
     Bucklin-Comiskey, S A. PCR protocol for rapid detection of
     Cercospora beticola in infected plant tissues. Journal of Sugar
     beet Research 40:1-2. 2003.

239. Lartey, R.T. and T. C. Caesar-TonThat (2005) DEGRADATION OF
     CERCOSPORIN BY LACCASE. (US Patent \# 6,872388)

240. Lartey, R.T., Caesar-TonThat, T.C., Caesar A. J., Shelver, W. L.,
     Sol, N. I and Bergman, J. W. Safflower: A new host of *Cercospora
     beticola.* Plant Disease. 89:797-801. 2005.

241. Leib, B.G., J.D. Jabro and G.R. Matthews. Field Evaluation and
     Performance Comparison of Soil Moisture Sensors. Soil Science
     168:396-408. 2003.

242. Lerch, R.N., Kitchen, N.R., Kremer, R.J., Donald, W.W., Alberts,
     E.E., Sadler, E.J., Sudduth, K.A., Myers, D.B., and Ghidey F.
     Development of a conservation-oriented precision agriculture
     system: Water and soil quality assessment. J. Soil Water Conserv.
     60 (6): 411-421. 2005.

243. Li, Y., McCrory, D. F., Powell, J. M., Saam, H. and Jackson-Smith,
     D.B. Heavy metal concentrations in dairy feed: A survey of heavy
     metal concentrations in Wisconsin dairy feeds. J. Dairy Sci.
     88:2911-2922. 2005.

244. Liao, C.H., Honeycutt, C.W., Griffin, T.S., and Jemison, J.M.
     Occurrence of gastrointestinal pathogens in soil of potato field
     treated with liquid dairy manure. Food Agric. Environ. 1:224-228.
     2003.

245. Liebig, M.A., Carpenter-Boggs, L., Johnson, J.M., Wright, S.E.,
     Barbour, N.W. Cropping System Effects on Soil Biological
     Characteristics in the Great Plains. Renewable Agric. Food Systems
     20(1):36-48. 2006.

246. Liebig, M.A., Carpenter-Boggs, L., Johnson, J.M., Wright, S.E.,
     Barbour, N.W. Cropping System Effects on Soil Biological
     Characteristics in the Great Plains. Renewable Agric. Food Systems
     20(1):36-48. 2006.

247. Liebig, M.A., Gross, J.R., Kronberg, S.L., Hanson, J.D., Frank,
     A.B., Phillips, R.L. Soil Response to Long-Term Grazing in the
     Northern Great Plains of North America. Agric. Ecosys. Environ.
     115:270-276. 2006.

248. Lin**,** C.H., McGraw, R.L., George, M.F. and Garrett, H.E. 2001.
     Nutritive quality and

249. Locke, M.A., R.M. Zablotowicz, P.J. Bauer, R.W. Steinriede, and
     L.A. Gaston. 2005. Conservation cotton production in the southern
     United States: herbicide dissipation in soil and cover crops. Weed
     Science 53:717-727.

250. Logsdon, S.D., T.C. Kaspar, D.W. Meek, and J.H. Prueger. 2002.
     Nitrate leaching as influenced by cover crops in large soil
     monoliths. Agron. J. 94(4):807-814.

251. Lu, Y.-C., Camp, C. R., and Sadler, E. J. Efficient allocations of
     irrigation water and nitrogen fertilizer in corn production. J.
     Sustainable Agric. 24(4):97-111. 2004.

252. Lu, Y.-C., Camp, C. R., and Sadler, E. J. 2004. Optimal levels of
     irrigation in corn production in the southeast coastal plain. J.
     Sustainable Agric. 24(1):995-106.

253. Lu, Y.-C., Sadler, E. J., and Camp, C. R. Economic feasibility
     study of variable irrigation of corn production in Southeast
     Coastal Plain. J. Sustainable Agric. 26(3):69-81. 2005.

254. Luckeydoo, L., Fausey, N., Brown, L., Davis, C. Early development
     of vascular vegetation of constructed wetlands in northwest Ohio
     receiving agricultural waters. Agricultural Ecosystems and the
     Environment 88: 89-94. 2002.

255. Luckeydoo, L.M. A periphyton sampler which minimizes site
     disturbance. Journal of Freshwater Ecology. 19(2): 339. 2004.

256. Ma, L. and Selim, H.M. Predicting pesticide transport in
     mulch-amended soils: a two-compartment model. Soil Sci. Soc. Am. J.
     69:318-327. 2005.

257. Ma, L., Hoogenboom, G., Ahuja, L. R., Ascough II, J. C., and
     Saseendran, S. A. Development and evaluation of RZWQM-CERES-maize
     hybrid for corn production. Agric. Systems. 87:274-295. 2006. 

258. Ma, L., Hoogenboom, G., Ahuja, L.R., Nielsen, D. C., and Ascough
     II, J.C. Development and evaluation of RZWQM-CROPGRO hybrid for
     soybean production. Agron. J. 97:1172-1182. 2005.

259. Ma, L., Nielsen, D. C., Ahuja, L. R., Malone, R. M., Saseendran, S.
     A., Rojas, K. W., Hanson, J. D., and Benjamin, J. G. Evaluation of
     RZWQM under varying irrigation levels in Eastern Colorado. Trans.
     ASAE. 46:39-49. 2003.

260. Ma, Q. L., Wauchope, R.D., Ma, L., Rojas, K.W., Malone, R.W., and
     Ahuja, L.R. Test of the Root Zone Water Quality Model (RZWQM) for
     predicting runoff of atrazine, alachlor and fenamiphos species from
     conventional-till corn mesoplots. Pest Manag. Sci. 60: 267-276.
     2004.

261. Ma, Q., Rahman, A., James, T. K., Holland, P. T., McNaughton, D.
     E., Rojas, K.W., and Ahuja, L. R. Modeling the fate of Acetochlor
     and terbuthylazine in the field using the Root Zone Water Quality
     Model. Soil Sci. Soc. Am. J. 68: 1491-1500. 2004.

262. Ma, Q.L., Wauchope, R.D., Rojas, K.W., Ahuja, L.R., Ma, L., and
     Malone, R.W. The pesticide module of the Root Zone Water Quality
     Model (RZWQM): testing and sensitivity analysis of selected
     algorithms for pesticide fate and surface runoff. Pest Manag. Sci.
     60: 240-252. 2004.

263. Makus, D. J. Effect of kaolin (Surround) on pepper fruit and seed
     mineral nutrients. Subtropical Plant Science 57:5-9. 2005.

264. Makus, D. J. Mycorrhizal inoculation of tomato and onion
     transplants improves earliness. In (Vavrina, C.S. et al eds.) Proc.
     XXVI IHC - Transplant Production and Stand Establishment. Acta
     Horticulturae 631:275-281. 2004.

265. Malik, N. S. A., and Bradford, J. M. A simple protein extraction
     method for proteomic studies on olive leaves. Journal of Food,
     Agriculture and the Environment 3:246-248. 2005.

266. Malik, N. S. A., and Bradford, J. M. Design and construction of an
     inexpensive Plexiglas chilling chamber to study flowering in olives
     (*Olea europaea* L.). HortScience 40:496-497. 2005.

267. Malik, N. S. A., and Bradford, J. M. Genetic diversity and clonal
     variation among olive cultivars offer hope for selecting cultivars
     for Texas. Journal of the American Pomological Society 58:203-209.
     2004.

268. Malik, N. S. A., and Bradford, J. M. Is chilling a prerequisite for
     flowering and fruiting in "Arbequina" olives? International Journal
     of Fruit Science 5:29-37 2006.

269. Malik, N. S. A., and Bradford, J. M. Reciprocal grafting between
     early maturing and normal maturing olive varieties: Preliminary
     effects on the nature of juvenility and flowering. Journal of Food,
     Agriculture and the Environment 2:197-200. 2004.

270. Malik, N.S.A., and Bradford, J. M. Regulation of flowering in
     'Arbequina' olives under non-chilling conditions: the effect of
     high daytime temperatures on Blooming. Journal of Food, Agriculture
     and the Environment 4: 84-87. 2006.

271. Malik, N.S.A., and Bradford, J.M. Flowering in 'Arbequina' olives
     in subtropical climate where olives normally remain vegetative.
     Accepted by International Journal of Fruit Science May 2005, to
     appear in vol. 5, issue 4.

272. Malik, N.S.A., and Bradford, J.M. Plant growth regulatory effects
     of chicken litter extract. Accepted by Journal of Sustainable
     Agriculture, February, 2006.

273. Malone, R. W., Ahuja, L. R., Ma, L., Wauchope, R. D., Ma, Q.L., and
     Rojas, K.W. Application of the Root Zone Water Quality Model
     (RZWQM) to pesticide fate and transport: an overview. Pest Manag.
     Sci. 60:205-221. 2004.

274. Malone, R. W., Ma, L., Wauchope, R. D., Ahuja, L. R., Rojas, K. W.,
     Ma, Q. L., Warner, R., and Byers, M. Modeling hydrology, metribuzin
     degradation and metribuzin transport in macroporous tilled and
     no-till silt loam soil using RZWQM. Pest Manag. Sci. 60:253-266.
     2004.

275. Malone, R., Weatherington-Rice, J., Shipitalo, M., Fausey, N., Ma,
     L., Ahuja, L.R., Wauchope, R.D., and Ma, Q.L. Herbicide leaching as
     affected by macropore flow and within-storm rainfall intensity
     variation: a RZWQM simulation. Pest Manag. Sci. 60:277-285. 2004.

276. Malone, R.W., Logsdon, S., Shipitalo, M.J., Weatherington-Rice, J.,
     Ahuja, L.R., and Ma, L. Tillage effect on macroporosity and
     herbicide transport in percolate. Geoderma 116:191-215. 2003.

277. Malone, R.W., Shipitalo, M.J., Ma, L., Ahuja, L.R. and Rojas, K.W.
     Macropore component assessment of the Root Zone Water Quality Model
     (RZWQM) using no-till soil blocks. Trans. ASAE 44:843-852. 2001.

278. Manley, D.G., J.A. Durant, P.J. Bauer, and J.R. Fredrick. 2003. Rye
     Cover Crop, Surface Tillage, Crop Rotation, and Soil Insecticide
     Impact on Thrips Numbers in Cotton in the Southeastern Coastal
     Plain. J. Agric. Urban Entomol. 19(4):217-226.

279. Mansell, R.S., Ma, L., Ahuja, L.R., and Bloom, S.A. Adaptive grid
     refinement in numerical models for water flow and solute transport
     in soil: A review. Vadose Zone J. 1:222-238. 2002.

280. Martin, S.W., Hanks, J.E., Harris, F.A., Wills, G.D., and
     Banerjee, S. Estimating total costs and possible returns from
     precision farming practices. Online. Crop Management
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281. Masin, R., Zuin, M., Archer, D. W., Forcella, F., and Zanin, G.
     WEEDTURF: A predictive model to aid control of annual weeds in
     turf. Weed Sci. 53:193-201. 2005.

282. Materon, L. A. and Zibilske, L. M. Remedial inoculation of
     Rhizobium meliloti strains and nodule occupancy on Medicago
     rigidula (L.). Applied Soil Ecology 23:155-163. 2003.

283. Materon, L. A. and Zibilske, L. M. Delayed inoculation and
     competition of nitrogen-fixing strains on Medicago noeana (Boiss.)
     and M. polymorpha (L.). Applied Soil Ecology 17:175-181. 2001.

284. Matthews, B.F., Devine, T.E**.,** Weismann, J.M., Beard, H.S.,
     Lewers, K.S., MacDonald, M.H., Park, Y.B., Maiti, R., Lin, J.J.,
     Kuo, J., Pedroni, M.J., Creagan, P.B., Saunders, J.A. Incorporation
     of sequenced cDNA and genomic markers into the soybean genetic map.
     Crop Sci. 41:516-521. 2001.

285. McComb, B.C., Bilsland, D. and Steiner, J.J. Associations of winter
     birds with riparian condition in the lower Calapooia watershed,
     Oregon. Northwest Sci. 79:164-171. 2005.

286. McMaster, G.S. Modeling field crop and rangeland canopy
     development, structure, and dynamics. Acta Horticulturae
     593:165-170. 2002.

287. McMaster, G.S., Ascough II, J.C., Nielson, D.C., Byrne, P.F.,
     Haley, S.D., Shaffer, M.J., Andales, A.A., and Dunn, G.A. Using
     species-based plant parameters in GPFARM: Complications of
     varieties and the G x E interaction in wheat. Transactions of the
     American Society of Agricultural Engineers. 46(5):1337-1346. 2003. 

288. McMaster, G.S., Ascough II, J.C., Dunn, G.H., Weltz, M.A., Shaffer,
     M.J., Palic, D., Vandenberg, B.C., Bartling, P.N.S., Edmunds, D.,
     Hoag, D.L., and Ahuja, L.R. Application and testing of GPFARM: A
     farm and ranch decision support system for evaluating economic and
     environmental sustainability of agricultural enterprises. Acta
     Horticulturae 593:171-177. 2002.

289. McMaster, G.S., Ascough II, J.C., Dunn, G.H., Weltz, M.A., Shaffer,
     M.J., Palic, D., Vandenberg, B.C., Bartling, P.N.S., Edmunds, D.,
     Hoag, D.L., and Ahuja, L.R. Application and testing of GPFARM: A
     farm and ranch decision support system for evaluating economic and
     environmental sustainability of agricultural enterprises. Acta
     Horticulturae 593:171-177. 2002. 

290. McMaster, G.S., Ascough II, J.C., Shaffer, M.J., Deer-Ascough,
     L.A., Byrne, P.F., Nielsen, D.C., Haley, S.D., Andales, A.A., and
     Dunn, G.H. GPFARM plant model parameters: Complications of
     varieties and the genotype x environment interaction in wheat.
     Trans. ASAE. 46(5):1337-1346. 2003.

291. McMaster, G.S., Palic, D.B., and Dunn, G.H. Soil management alters
     seedling emergence and subsequent fall growth and yield in dryland
     winter wheat-fallow systems in the Central Great Plains on a clay
     loam soil. Soil & Tillage Research. 65:193-206. 2002. 

292. McMaster, G.S., Wilhelm, W.W., Palic, D.B., Porter, J.R., and
     Jamieson, P.D. Spring wheat leaf appearance and temperature:
     Extending the paradigm? Annals of Botany. 91:697-705. 2003. 

293. McMurtrey, J.E., Daughtry, C.S.T., Devine, T.E. and Corp, L.A.
     Spectral detection of crop residues for soil conservation from
     conventional and large biomass soybean. Agron. Sustain. Dev.
     25:25-33. 2005.

294. Mebrahtu T., Devine T.E**.,** Donald P., Abney T.S. Registration of
     'Randolph' Vegetable Soybean. Crop Sci. 45:2644-2645. 2005.

295. Mebrahtu, T., Devine, T.E**.,** Donald, P. Abney, T.S. Registration
     of Asmara vegetable soybean. Crop Sci. 45:408-409. 2005.

296. Merrill, S.D., Tanaka, D.L., Krupinsky, J.M. 2004. Water Use and
     Depletion by Diverse Crop Species on Haplustoll Soil in the
     Northern Great Plains. Journal of Soil and Water Conservation. V.
     59(4):176-183.

297. Middleton, E.M., Kim, M.S., Krizek, D.T., Bajwa, R.K.S. Evaluating
     UV-B effects and EDU protection in soybean leaves using
     fluorescence. Photochemistry and Photobiology 81(5):1075.

298. Middleton, E.M., Kim, M.S., Krizek, D.T., Bajwa, R.K.S. Evaluating
     UV-B effects and

299. Mills, D.J., Coffman, C.B., Teasdale, J.R., Everts, K.B.,
     Abdul-Baki, A.A., Lydon, J. and Anderson, J.D. Foliar disease in
     fresh-market tomato grown in differing bed strategies and fungicide
     spray programs. Plant Dis. 86:955-959. 2002.

300. Mills, D.J., Coffman, C.B., Teasdale, J.R., Everts, K.B., and
     Anderson, J.D. Factors associated with foliar disease of staked
     fresh market tomatoes grown under differing bed strategies. Plant
     Dis. 86:356-361. 2002.

301. Misselbrook, T.H., Powell, J.M., Broderick, G.A., and Grabber,
     J.H. 2005. Dietary manipulation in dairy cattle to reduce ammonia
     emissions. J. Dairy Sci. 88:1765-1777.

302. Montgomery, M.B., Ohno, T., Griffin, T.S., Honeycutt, C.W., and
     Fernandez, I.J. Phosphorus mineralization and availability in soil
     amended with biosolids and animal manures. Biol. Agric. Hort.
     22:321-334. 2005.

303. Morgan, J.A., Skinner, H.R., and Hanson, J.D. Nitrogen and CO2
     affect regrowth and biomass partitioning differently in forages of
     three functional groups. Crop Science J. 41:78-86. 2001. 

304. Mueller-Warrant, G. W. and Rosato, S. C. Weed control for stand
     duration perennial ryegrass seed production: I Residue removed.
     Agron*. J.* 94:1181-1191. 2002.

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416. Schomberg H.H., Langdale G.W., Franzluebbers A.J., and Lamb M.C.
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     Piedmont soil. Agron. J. 95:1281--1287. 2003.

417. Schomberg, H., Endale, D., Calegari, A., Peixoto, R., Miyazawa, M.
     and Cabrera, M. 2006. Influence of cover crops on potential
     nitrogen availability to succeeding crops in a Southern Piedmont
     soil. Biology and Fertility of Soils 42, 299-307.\
     Schomberg, H., Lewis, J., Tillman, G., Olson, D., Timper, P.,
     Wauchope D., Phatak S. and Jay M. Conceptual model for sustainable
     cropping systems in the southeast: cotton system. J. Crop
     Production 8:307-327. 2003.\
     Schomberg, H., Lewis, J., Tillman, G., Olson, D., Timper, P.,
     Wauchope D., Phatak S. and Jay M. Conceptual model for sustainable
     cropping systems in the southeast: cotton system. J. Crop
     Production 8:307-327. 2003.

418. Number range CHAPTERSchwab, E.B., D.W. Reeves, C.H. Burmester, and
     R.L. Raper. 2002. Conservation tillage systems for cotton grown on
     a silt loam soil in the Tennessee Valley. Soil Sci. Soc. Am. J.
     66:569-577.

419. Shaffer, M.J. Nitrogen modeling for soil management. J. Soil and
     Water Conservation. 57:417-424. 2002.

420. Shaffer, M.J., Bartling, P.N.S., and McMaster, G.S. GPFARM modeling
     of corn yield and residual soil nitrate-N. Computers and
     Electronics in Agriculture. 43:87-107. 2004.

421. Shaffer, M.J., Newton, B.J., and Gross, C.M. An internet-based
     simulation model for Nitrogen management in agricultural settings.
     The Scientific World. 1:728-736. 2001.

422. Shaik, S.A., Terrill, T.H., Miller, J.E., Kouakou, B., Kannan, G.,
     Kaplan R.M., Burke, J.M. and J. Mosjidis, J. Sericea lespedeza hay
     as a natural deworming agent against Haemonchus contortus infection
     in goats. Vet. Parasitol. 2006.

423. Sharratt, B.S. and Gesch, R.W. Rooting characteristics and water
     requirements of *Cuphea*. pp. 203-205. In: Janick, J. (ed.) New
     Crops and New Uses: Strength in diversity, Proc. Fifth National New
     Crops Symp., Atlanta. GA. 2001.

424. Sharratt, B.S. and R.W. Gesch. Water use and root length density of
     *Cuphea* influenced by row spacing and sowing date. Agronomy
     Journal 96:1475-1480. 2004.

425. Shaver, T.M., Peterson, G.A., Ahuja, L.R., Westfall, D.G., Sherrod,
     L.A., and Dunn, G.H. Surface soil physical properties after twelve
     years of dryland no-till management. Soil Sci. Soc. Am. J.
     66:1296-1303. 2002.

426. Shaver, T.M., Peterson, G.A., Ahuja, L.R., Westfall, D.G., Sherrod,
     L.A., and Dunn, G.H. Surface soil physical properties after twelve
     years of dryland no-till management. Soil Sci. Soc. Am. J.
     66:1296-1303. 2002.

427. Shaver, T.M., Peterson, G.A., and Sherrod, L.A. Cropping
     intensification in dryland systems improves soil physical
     properties: regression relations. Geoderma. 116:149-164. 2003.

428. Sherrod, L.A., Peterson, G.A., Westfall, D.G., and Ahuja, L.R.
     Cropping intensity enhances soil organic carbon and nitrogen in a
     no-till agroecosystem. Soil Sci. Soc. Am. J. 67: 1533-1543. 2003.

429. Siemens, M.C., and Wilkins, D.E. Effect of residue management
     methods on no-till drill performance. Appl. Eng. Agric. 22(1):
     51-60. 2006.

430. Siemens, M.C., Correa, R.F., and Wilkins, D.E. Flexible
     ground-driven residue management wheel. U.S. Patent No. US
     6,345,671 B1. 2002.

431. Siemens, M.C., Wilkins, D.E., and Correa, R.F. Development and
     evaluation of a residue management wheel for hoe-type no-till
     drills. Trans. ASAE 47(2):397-404. 2004.

432. Singer, J.W., and K.A. Kohler. 2005. Rye cover crop management
     affects grain yield in a soybean-corn rotation. Online. Crop
     Management doi:10.1094/CM-2005-0224-02-RS.

433. Siri-Prieto, G., Reeves, D.W., and Raper, R.L. Tillage requirements
     for integrating winter-annual grazing in cotton production: plant
     water status and productivity. Soil Sci. Soc. Amer. J. 200x. In
     Press.

434. Skinner, R.H., Hanson, J.D., Hutchinson, G.L., and Schuman, G.E.
     Response of C3 and C4 grasses to supplemental summer
     precipitation. J. of Range Management. 55:517-522. 2002.

435. Sorensen, R.B., Sconyers, L.E., Lamb, M.C. and Sternitzke, D.A Row
     Orientation and Seeding Rate on Yield, Grade, and Stem Rot of
     Peanut with Subsurface Drip Irrigation. Peanut Sci. 31: 54-58.
     2004.

436. Stamps, W.T., T.L. Woods, M.J. Linit, and H.E. Garrett. 2002.
     Arthropod diversity in alley cropped black walnut (*Juglans nigra*
     L.) stands in eastern Missouri, USA. Agroforestry Systems. 56(2):
     167-175.

437. Starks, P.J., Heathman, G.C., Ahuja, L.R., and Ma, L. Use of
     limited soil property data and modeling to estimate root zone soil
     water content. J. Hydrol. 272:131-147. 2003.

438. Starr, G.C. Assessing temporal stability and spatial variability of
     soil water patterns with implications for precision water
     management. Agricultural Water Management. 72:223-243. 2005.

439. Starr, G.C., Cooley, E.T. Lowery, B. and Kelling, K. Soil water
     fluctuations in a loamy sand under irrigated potato. Soil Science
     170:77-89. 2005.

440. Steiner, J. J., Griffith, S. M., Mueller-Warrant, G. W.,
     Whittaker, G. W. Banowetz, G. M. and Elliott, L. F.. Conservation
     Practice Impacts in Western Oregon Perennial Grass Seed Systems. I:
     Direct Seeding and Maximal Residue Management. Agron J 98: 177-186.
     2006.

441. Steiner, J. J., Minoura, T. and Xiong, W. WeatherInfo: A web-based
     weather data capture system. Agron. J. 97:633-639. 2005.

442. Steiner, J.J., Minoura, T. and Imaeda, M. An automated template
     approach for generating Web-based conservation planning worksheets.
     Agron. J. 98: in press. 2006.

443. Sternitzke, D.A., Lamb, M.C., Davidson, J.I., Jr., Barron, R.T. and
     Bennett, C.T. Impact of plant spacing and population on yield for
     single-row non-irrigated peanuts. Peanut Sci. 27:52-56. 2000.

444. Stone, K.C., Sadler, E.J., Millen, J.A., Evans, D.E., and Camp,
     C.R. Water flow rates from a precision irrigation system. Appl.
     Eng. Agric. 22(1):73-78. 2006.

445. Sudduth, K.A., Drummond, S.T., and Kitchen, N.R. Accuracy issues in
     electromagnetic induction sensing of soil electrical conductivity
     for precision agriculture. Comp. Elect. Agric. 31(3):239-264. 2001.

446. Sudduth, K.A., Hummel, J.W., and Drummond, S.T. Comparison of the
     Veris Profiler 3000 to an ASAE-standard penetrometer. Appl. Eng.
     Agric. 20(5):535-541. 2004.

447. Sudduth, K.A., Kitchen, N.R., Bollero, G.A., Bullock, D.G., and
     Wiebold, W.J. Comparison of electromagnetic induction and direct
     sensing of soil electrical conductivity. Agron. J. 95: 472-482.
     2003.

448. Sudduth, K.A., Kitchen, N.R., Wiebold, W.J., Batchelor, W.D.,
     Bollero, G.A, Bullock, D.G., Clay, D.E., Palm, H.L., Pierce, F.J.,
     Schuler, R.T., and Thelen, K.D. Relating apparent electrical
     conductivity to soil properties across the north-central USA. Comp.
     Elect. Agric. 46:263-283. 2005.

449. Tanaka, D.L., Anderson, R.L., and Rao, S.C. Crop sequencing to
     improve use of precipitation and synergize crop growth. Agron. J.
     97:385-390. 2004.

450. Tanaka, D.L., Krupinsky, J.M., Liebig, M.A., Merrill, S.D.,
     Hendrickson, J.R., Johnson, H.A., and Hanson J.D. Dynamic cropping
     systems: an adaptable approach to crop production in the Great
     Plains. Agron. J. 94:957-961. 2002.

451. Tanaka, D.L., Karn, J.F., Liebig, M.A., Kronberg, S.L., and Hanson,
     J.D. An integrated approach to crop/livestock systems: Forage and
     grain production for swath grazing. Renewable Agric. Food
     Sys.20(4): 223-231. 2005.

452. Tarpley, L. and Sassenrath, G.F. 2003. Environmental and
     physiological components of the cotton leaf reflectance spectrum,
     pp.95-109. *In* T. Van Toai, ed. Digital Imaging and Spectral
     Techniques: Application to Precision Agriculture. American Society
     of Agronomy Special Publication No. 66. pp. 253. 2003.

453. Taylor, J.E., J.E., T.G. Bellarmine, D. Timlin, V.R. Reddy.
     Developing Appropriate Technology for Small-scale Farming
     Populations. Environmental Informatics Archives 2:10-14. 2004

454. Teasdale, J.R. Devine, T.E., Mosjidis, J.A., Bellinder, R.R., and
     Beste, C.E. Growth and development of hairy vetch cultivars in the
     northeastern United States as influenced by planting and harvesting
     date. Agronomy J. 96:1266-1271. 2004.

455. Teasdale, J.R., Abdul-Baki, A.A., Mills, D.J., and Thorpe, K.W.
     Enhanced pest management with cover crop mulches. Acta
     Horticulturae 638:135-140. 2004.

456. Teasdale, J.R., and Pillai, P. Contribution of ammonium to
     stimulation of smooth pigweed germination by extracts of hairy
     vetch residue. Weed Biol. Manag. 5:19-25. 2005.

457. Teasdale, J.R., R.W. Mangum, J. Radhakrishnan, and M.A.
     Cavigelli. 2004. Weed seedbank dynamics in three organic farming
     crop rotations. Agron. J. 96:1429-1435.

458. Teasdale, J.R., R.W. Mangum, J.R. Radhakrishnan, and M.A.
     Cavigelli. 2003. Factors influencing annual fluctuations of the
     weed seedbank at the long-term Beltsville Farming Systems Project.
     Aspects Appl. Biol. 69:93-99.

459. Terra, J. A., J.N. Shaw, D.W. Reeves, R.L. Raper, E. vanSanten and
     P.L. Mask. 2004. Soil carbon relationships with terrain attributes,
     electrical conductivity, and a soil survey in a coastal plain
     landscape. Soil Sci.169:819-831.

460. Terra, J.A., D.W. Reeves, J.N. Shaw and R.L. Raper. 2005. Impacts
     of landscape attributes on carbon (C) sequestration during the
     transition from conventional to conservation management practices
     on a Coastal Plain field. J. Soil & Water Conserv. 60(6):437-446.

461. Terra, J.A., J.N. Shaw, D. W. Reeves, R. L. Raper, E. van
     Santen, E. B. Schwab, and P. L. Mask. Soil management and landscape
     variability affects field-scale cotton productivity. Soil Sci. Soc.
     Am. J. 70:98-107. 2005.

462. Thomson, S.J. and Brazil, B.L. Evaluation of a low-cost, high
     capacity, thermocouple selection unit. Applied Engineering in
     Agriculture. Volume 18, Number 4, pp. 505-511. 2002.

463. Thomson, S.J., Hanks, J.E., and Sassenrath-Cole, G.F. Continuous
     geo-referencing for video-based remote sensing on agricultural
     aircraft. Transactions of the ASAE 45(4). 2002.

464. Thorne, M.E., F.L. Young, W.L. Pan, R. Bafus, and J.R. Alldredge.
     No-till spring cereal cropping systems reduce wind erosion
     susceptibility in the wheat/fallow region of the Pacific
     Northwest. J. Soil and Water Cons. 58(3):250-257. 2003.

465. Tillman, G., Schomberg, H., Phatak, S., Mullinix, B., Lachnicht,
     S., Timper, P., Olson, D. Influence of cover crops on insect pests
     and predators in conservation tillage cotton. Journal of Economic
     Entomology 97:1217-1232. 2004.

466. Timlin, D.J. Pachepsky, Ya., and van Genuchten, M. Th. 2001.
     2DSOIL, A modular simulator of soil and root processes. Ver 0.3.
     USDA-ARS Alternate Crops and Systems Laboratory Special Publication
     #1.

467. Timlin, D.J., Reddy, G.K., Acock, B., E. Mironenko, Ya. Pachepsky,
     and V. Reddy. GUICS: Graphic User Interface for Crop Simulation
     with Windows Version 2.4 USDA-ARS, Remote Sensing and Modeling
     Laboratory. Beltsville, MD. 1997, revised 2005

468. Number range CHAPTERTruman, C., W. Reeves, J. Shaw, A. Motta, C.
     Burmester, R. L. Raper, and E. Schwab. 2003. Tillage impacts on
     soil property, runoff, and soil loss variations from a Rhodic
     Paleudult under simulated rainfall. J. Soil Water Cons.
     58(5):258-267.

469. Waddell, J.T. and A.W. Lenssen. Impact of P Fertility on Dryland
     Legume N Production. 2006. Great Plains Soil Fertility Conference
     Proceedings, Vol. 11. Denver, CO. March 7-8, 2006 (published
     proceedings).

470. Walenta, D.L., J.P. Yenish, F.L. Young, and D.A. Ball.
     Vernalization response of plants grown from spikelets of spring and
     fall cohorts of jointed goatgrass. Weed Sci. 50:461-465. 2002.

471. Wang, D., Prato, A.A., Qiu, Z., Kitchen, N.R., and Sudduth, K.A.
     Economic and environmental evaluation of variable rate nitrogen and
     lime application for claypan soil fields. Precision Agric. 4:35-52.
     2003.

472. Number range CHAPTERWang, F., Fraisse, C.W., Kitchen, N.R., and
     Sudduth, K.A. Site-specific evaluation of the CROPGRO-soybean model
     on Missouri claypan soils. Agric. Systems 79:985-1005. 2003.

473. Wang, Q., Bryan, H.H. Klassen, W. Li, Y.C. Codallo, M. and
     Abdul-Baki, A. Improved tomato production with summer cover crops
     and reduced irrigation rates. Proc. Fla. State Hort. Soc.
     115:2002-2007. 2002.

474. Washington J.W., Endale D.M., Samarkina L.P., Chappell K.E. Kinetic
     control of oxidation state at thermodynamically buffered potentials
     in subsurface waters. Geochimica et Cosmochimica Acta 68(23):
     4831-4842, 2004.

475. Wauchope, R.D., Ahuja, L.R., Arnold, J.G., Bingner, R., Lowrance,
     R., Van Genuchten, M.T., and Adams, L.D. Software for pest
     management science: Computer models and databases from the U.S.
     Department of Agriculture- Agricultural Research Service. ARS.
     Special Issue of Pest Management Sci. 59:691-698. 2003.

476. Wauchope, R.D., Rojas, K.W., Ahuja, L.R., Ma, Q.L., Malone, R.W.,
     and Ma, L. Documenting the pesticide processes module of the ARS
     RZWQM Agro-ecosystem Model. Pest Manag. Sci. 60: 222-239. 2004.

477. Wesley, R.A., Elmore, C.D., and Spurlock, S.R. Deep Tillage and
     Crop Rotation Effects on Cotton, Soybean, and Grain Sorghum on
     Clayey Soils. Agronomy Journal. 93:170-178. 2001.

478. Westgate, L.R., J.W. Singer, and K.A. Kohler. 2005. Method and
     timing of rye control affects soybean development and resource
     utilization. Agron. J. 97(3):806-816.

479. Whittaker, G., Färe, R., Srinivasan, R. and Scott, D. W. Spatial
     evaluation of alternative nonpoint nutrient regulatory instruments.
     Water Resour. Res. Vol. 39 No. 4, WES 1-1 to WES 1-9. 2003.

480. Wigington, Jr., P.J., Griffith, S. M., Field, J. A. Baham, J. E.
     Horwath, W.R., Owen, J., Davis, J. H., Rain, S. C. and Steiner, J.
     J.. Effectiveness of a riparian water quality buffer along a small
     agricultural stream in western Oregon. J Environ Quality 32:
     162-170. 2003.

481. Wilkins, D.E, Siemens, M.C., and Albrecht, S.L. Changes in soil
     physical characteristics during transition from intensive tillage
     to direct seeding. Trans. ASAE 45(4):877-880. 2002.

482. Willers, J. L., Milliken, G. A., O'Hara, C. G. and Jenkins, J. N.
     Information Technologies and the Design and Analysis of
     Site-Specific Experiments Within Commercial Fields, pp. 41-73.
     *In*: G. Milliken (ed.), 16^th^ Appl. Stat. Agric. Conf.,
     Manhattan, KS, April 25-28, 2004. Stat. Dept., Kansas St. Univ.,
     Manhattan, KS. 2004. (Peer Reviewed Proceedings)

483. Wu, S., Lu, Y., McMurtrey, J.E., Weesies, G., Devine, T.E**.,** and
     Foster, G.R. Soil conservation benefits of large biomass soybeans
     for increasing crop residue cover. J. Sustainable Agriculture
     24:107-128. 2004.

484. Wuest, S. B., Caesar-TonThat, T. C., Wright, S. F., and
     Williams, J. D. 2005. Organic matter addition, N, and residue
     burning effects on infiltration, biological, and physical
     properties of an intensively tilled silt-loam soil. Soil & Tillage
     Research 84:154-167.

485. Young, F.L., Yenish, J.P., Walenta, D.L., Bell, D.A. and Alldredge,
     J.R. Spring germinating jointed goatgrass (*Aegilops cylindrical*)
     produces viable spikelets in spring-seeded wheat. Weed Sci.
     51:379-385. 2003.

486. Young, F.L. Long-term weed management studies in the Pacific
     Northwest. Weed Sci 52:897-903. 2004.

487. Young. F.L., and *M.E. Thorne*. Weed-species dynamics and
     management in no-till and reduced-till fallow cropping systems for
     the semi-arid agricultural region of the Pacific Northwest, USA.
     Crop Protection. 23:1097-1110. 2004.

488. Yu, Q., Saseendran, S.A., Ma, L., Flerchinger, G.N., Green, T.R.,
     and Ahuja, L.R. Modeling a wheat-maize double cropping system in
     China using two plant growth modules with RZWQM. Agric. Systems.
     89:457-477. 2006.

489. Zhu, H., Butts, C.L., Lamb, M.C., and Blankenship, P.D. An
     Implement to Install and Retrieve Surface Drip Irrigation Laterals.
     Applied Eng. in Agriculture. 20(1):17-23. 2004.

490. Zhu, H., Lamb, M.C., Butts, C.L., and Blankenship, P.D. Improving
     Peanut Yield and Grade with Surface Drip Irrigation in Undulated
     Topographic Fields. Trans. ASAE 47(1):99-106. 2004.

491. Zibilske, L. M. and Bradford, J. M. Tillage effects on phosphorus
     mineralization and microbial activity. Soil Science
     168(10):677-685. 2003.

492. Zibilske, L. M., Bradford, J. M. and Smart, J. R. Conservation
     tillage induced changes in organic carbon, total nitrogen and
     available phosphorus in a semi-arid alkaline subtropical soil. Soil
     & Tillage Research 66:153-163. 2002.

493. Zibilske, L.M., and L.A. Materon. Biochemical properties of
     decomposing cotton and corn stem and root residues. Soil Science
     Society of America Journal 69:378-386. 2005.

# Non-Peer Reviewed Publications

1.  Abdul-Baki, A., Aslan, S. Carrera, L.M. and Linderman, R. Management
    Practices for Early Harvest of Table Grape Vineyards in the
    Coachella Valley. Coachella Valley Resource Conservation District.
    32 p. 2002.

2.  Abdul-Baki, A., Aslan, S. Linderman, R. Cobb, S. and Davis, A. Soil,
    Water and Nutritional Management of Date Orchards in the Coachella
    Valley and BARD. California Date Commission, Coachella Valley
    Resource Conservation District. 40 p. 2002.

3.  Abrahamson D.A., Endale D.M., Schomberg H.H. A modeling approach to
    assess the water balance of a typical Southern Piedmont catchment
    under long-term no-till usage. Proceedings of the 2003 Georgia Water
    Resources Conference. v. II. p. 884-887. 2003.

4.  Adams, L-N., J.M. Powell, G.A. Broderick and L.D. Satter. Whole-farm
    nutrient management on dairy farms: The diet connection. An
    educational slide collection for consultants, educators, and other
    professionals who provide assistance to dairy farmers on issues
    related to dietary practices. Nutrient and Pest Management Program,
    University of Wisconsin Cooperative Extension. 2002.

5.  Alderman, S. and Pfender, W. 2000. Integrated pest management of
    diseases of grasses grown for seed in Oregon. Pages 189-196 *in*:
    IPM in Oregon: Achievements and Future Directions. M. Shenk and M.
    Kogan, eds. Oregon State University Extension Service Special Report
    1020.

6.  Alva, A., Marcos, J., Stockle, C. Reddy, V.R. and Timlin, D. CroSyst
    VB-Simpotato, a crop simulation model for potato-based cropping
    systems: II. Evaluation of Nitrogen Dynamics. Proc. Of the 4th
    International Crop Science Congress, September 26-October 1, 2004,
    Brisbane, Australia. (5 pages) 2004.

7.  Archer, D. W. Drift Prairie Conservation Ag.: Economics Five-Year
    Report. In: Jacobson, B. and S. Clancy, Final Report on Conservation
    Agriculture: Demonstration Farm Project of The Natural Resources
    Trust. Bismarck, ND. p. 83-88. 2005.

8.  Archer, D.W., Eklund, J.J., Walsh, M., Forcella, F. Weedem: a
    User-Friendly Software Package for Predicting Annual Ryegrass and
    Wild Radish Emergence. Jacob, H.S., Editor. Plant Protection Society
    of WA, INC., Melbourne, Australia. Proceedings of Australian Weed
    Science Society. p. 446-449. 2002. (Proceedings)

9.  Archer, D.W., Forcella, F., Wiersma, J.J., Durgan, B.R. 2005.
    Wheatscout: Wild Oat and Foxtail Herbicide Decision Model. In: 27th
    Annual Zero Tillage and Winter Wheat Workshop, February 1-2, 2005,
    Brandon, Canada. p. 59-65.

10. Archer, D.W., Pikul, J. L., Jr., and Riedell, W. E. Analyzing risk
    and risk management in cropping systems. In: Hanson, J.D. and J.M.
    Krupinsky (eds.), Proceedings of the Dynamic Cropping Systems:
    Principles, Processes, and Challenges. Bismarck, ND. p.155-164.
    2003.

11. ARS Magazine "No-till Plus Poultry Litter Raises Cotton Yields in
    Drought. Article describing Endale and Schomberg research. January
    54:14-15. 2006.

12. Ashford, D., Reeves, D.W. 2002. Rolling and Crimping-Scientists
    Study Alternative Cover Crop Kill Method. Highlights Online.
    Available from:
    [http://www.ag.auburn.edu/resinfo/highlightsonline/fall01/fall‑ashford.html](http://www.ag.auburn.edu/resinfo/highlightsonline/fall01/fall%1Eashford.html)

13. Balkcom, K.S., Rowland, D.L. and Lamb, M.C. Cotton Yields in
    Conventional and Conservation Tillage Systems under Different
    Irrigation Levels. National Cotton Council Beltwide Cotton
    Conference. \[CD-Rom\]. (Proceedings)

14. Balkcom, K.S., D.W. Reeves, J.M. Kemble, and R.A. Dawkins. Winter
    annual grazing and tillage systems effects on sweet corn. Proc.
    26^th^ Southern Conservation Tillage Conference for Sustainable
    Agriculture, June 8-9, 2004, Raleigh, NC. North Carolina
    Agricultural Research Service Technical Bulletin TB-321. p. 205-208.
    2004.

15. Banowetz, G. M., Steiner, J. J., Boatang, A. and El-Nashaar, H..
    Potential for On-farm Conversion of Straw to Bioenergy in Seed
    Producing Operations. Seed Prod. Res. at Oregon State Univ.,
    USDA-ARS Cooperating. p 75-78. 2005.

16. Bauer, P. J., J. R. Frederick, and W. J. Busscher. 2002. Optimizing
    conservation tillage production: Soil specific effects of management
    practices on cotton, soybean, and wheat. pp. 382-385. In Proc. 25th
    Ann. So. Conservation Tillage Conf. for Sustainable Agriculture,
    24-26 June, Auburn, AL. (CD-ROM)

17. Bjorneberg D.L., C. Prestwich and R.G. Evans, 2005. Evaluating the
    Surface Irrigation Soil Loss (SISL) Model. Presented at ASABE Annual
    International Conference, ASABE Technical Paper 052033. July 17-20.
    Tampa, FL 6 pp. Available on CDROM.

18. Boyd, N.S. and E.B. Brennan. (2004) Weed survival and seed
    production following rotary hoeing in a mixed cover crop.
    Proceedings of the California Conferences on Biological Control. pp.
    116-119. Berkeley, CA.

19. Boyd, N.S., Brennan, E.B. and S.A. Fennimore. (2005) Stale seedbed
    techniques for organic vegetable production. Organic Research
    Matters issue 2, p. 1-3.

20. Boydston, R. A. and Al-Khatib, K. Utilizing Brassica Cover Crops for
    Weed Suppression in Annual Cropping Systems *in* Handbook of
    Sustainable Weed Management, ed. H. P. Singh, D. R. Batish,
    and R. K. Kohli. Haworth Press, Binghamton, NY. Chapter 4,
    pp. 966. 2005. (Book Chapter)

21. Boydston, R. A. and Williams, M. M. II. Integrated weed management
    in vegetable crops. Proc. Pacific Northwest Vegetable Association
    Meetings, Pasco, WA, Nov. 17, pp 1-4, http://www.pnva.org. 2005.
    (Proceedings)

22. Boydston, R. A. Volunteer potato control in field and sweet corn.
    Proc. 42^nd^ Washington State Potato Conference pg. 57-67. 2003.
    (Proceedings)

23. Boydston, R. A., Hutchinson, P., and Ransom, C. New herbicides for
    weed management in potato production. Proc. 44^th^ Washington State
    Potato Conf., Pg. 1-3. 2005. (Proceedings)

24. Boydston, R. A., Mojtahedi, H., Crosslin, J. M., Thomas, P. E., and
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     Jan. 7-11.

296. Thomson, S.J., Fisher, D.K., and Thomas, D.L. Experiences with the
     UGA EASY evaporation pan for irrigation of cotton grown in Midsouth
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     Association, Falls Church, VA. 2002.

297. Thomson, S.J., Fisher, D.K., Sassenrath-Cole, G.F., Freeland, T.B.,
     and Pringle, H.C. Use of granular matrix sensors, models, and
     evaporation measuring devices for monitoring cotton water use and
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298. Thomson, S.J., Fisher, D.K., Sassenrath-Cole, G.F., Freeland, T.B.,
     and Pringle, H.C. Use of granular matrix sensors, models, and
     evaporation measuring devices for monitoring cotton water use and
     soil water status in the Mississippi Delta. *In* Proceedings of the
     Beltwide Cotton Production Research Conference, CD-ROM paper no.
     E025.pdf, National Cotton Council, Memphis, TN. 2002.

299. Tillman G., Schomberg H., Phatak S., Timper P., and Olson D.
     Enhancing sustainability in cotton with reduced chemical inputs,
     cover crops, and conservation tillage. Proc. 25th Southern
     Conservation Tillage Conference. p. 366-368. 2002.

300. Timlin, D.J., J. Starr, R. Cady, and T. Nicholson. Comparing Ground
     Water Recharge Estimates Using Advanced Monitoring Techniques and
     Models. NUREG/CR 6836, U.S. Nuclear Regulatory Commission,
     Washington, DC. 2003.

301. Timlin, D.J., J.L. Starr. R. Cady, T.J. Nicholson. Field Studies
     for Estimating Uncertainties in Ground Water Recharge Using Near
     Continuous Piezometer Data.NUREG/CR 6729, U.S. Nuclear Regulatory
     Commission, Washington, DC. 2001.

302. Timlin, D.J., Walthall, C. L, Pachepsky, Ya., Dulaney, W.P., and
     Daughtry, C.S.T. Spatial Regression of Crop Parameters with
     Airborne Spectral Imagery In: Proceedings of the Third
     International Conference on Geospatial Information in Agriculture
     and Forestry \[CD-ROM Computer file\], Denver, Colorado, 5 7
     November 2001. Veridian, Ann Arbor, MI, USA. 2001.

303. Truman, C., E. Schwab, R. Raper, and K. Balkcom. 2005. Paratilling
     frequency effects on runoff and soil loss for no-till systems in
     the Tennessee Valley Region of Alabama. p. 213. In Proc. Southern
     Conser. Tillage Syst. Conf. Clemson Univ., Florence, SC. 27-29 June
     2005.

304. USDA-NRCS Soil Quality Institute. 2002. The knife roller (crimper):
     an alternative kill method for cover crops. Technical Note #13.
     Sept.

305. USDA-NRCS Soil Quality Institute. Soil compaction: detection,
     prevention, and alleviation. Technical Note #17. June. 2003.

306. Waddell, J.T. and A.W. Lenssen. Impact of P Fertility on Dryland
     Legume N Production. 2006. Great Plains Soil Fertility Conference
     Proceedings, Vol. 11. Denver, CO. March 7-8, 2006 (published
     proceedings).

307. Walsh, M., Forcella, F., Archer, D.W., Eklund, J.J. Weedem: Turning
     Information into Action. Jacob, H.S., Dodd, J., Moore, J.H.,
     Editors. Weeds: Threats Now and Forever? 13th Australian Weed
     Science Society Papers and Proceedings. p. 446-449. 2002.

308. Walthall, C.L., Dulaney, W.P., Anderson, M., Norman, J., Fang, H.,
     Liang, S., Timlin, D., Pachepsky, L. Alternative Approaches for
     Estimating Leaf Area Index (Lai) from Remotely Sensed Satellite and
     Aircraft Imagery. In: Proceedings of the Spie International
     Symposium on Optical Science and Technology, August 2-6, 2004,
     Denver, Colorado. 5544: P. 241-255. 2004.

309. Webber, C.L., III, Davis, A.R., Shrefler, J.W., Perkins-Veazie, P.,
     Russo, V.M., and Edelson, J.V. Weed control in organic watermelon
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     Industries Show. 25:97-100. 2006.

310. Webber, C.L., III, Davis, A.R., Shrefler, J.W., Perkins-Veazie, P.,
     Russo, V.M., and Edelson, J.V. Organic weed control in two
     watermelon variety trials. Summer 2005, Lane and Center Point, OK.
     Vegetable Weed Control Report. MP-162. pp. 31-33. 2006.

311. Webber, C.L., III, Russo, V.M., and Shrefler, J.W. Corn gluten meal
     as a herbicide in non-pungent jalapeño peppers, pp. 57-58. In: L.
     Brandenberger and L. Wells (eds.). 2005 Vegetable Trial Report.
     Oklahoma State University Bull. MP-164. 2006.

312. Williams, J.D., Kitchen, N.R., and Scharf, P.C. Detecting spatially
     variable corn nitrogen needs using green reflectance from 35mm
     photographs. p. 183-190. In: Proc. North Central Extension-Industry
     Soil Fertility Conf., Ames, IA, Nov. 14-15. 2001.

313. Williams, J.D., Kitchen, N.R., Scharf, P.C., and Stevens, W.E.
     Aerial photography used to assess spatially variable corn nitrogen
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     MN, July 14-17, 2002. ASA, CSSA, and SSSA, Madison, WI. 2002.

314. Young III, W. C., Mellbye, M. E., Gingrich, G. A., Silberstein, T.
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     optimum nitrogen fertilization practices for grass seed production
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     USDA-ARS, Corvallis, OR, pp. 1-9. 2003.

315. Zibilske, L.M. Organic matter management effects on soil
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# Book Chapters:

1.  Ahuja, L.R. and Ma, L. Computer models to guide soil water
    management for plants, pp 218-222. In: Lal, R. (ed.) Encyclopedia of
    Soil Science, Marcel Dekker, Inc., NY. 2002

2.  Ahuja, L.R. and Ma, L. Parameterization of agricultural system
    models: Current issues and techniques, pp. 273-316. In Ahuja, L.R.,
    Ma, L. and Howell, T.A. (eds.) Agricultural System Models in Field
    Research and Technology Transfer, CRC Press. Boca Raton, FL. 341 pp
    2002.

3.  Ahuja, L.R. Quantifying Agricultural Management Effects on Soil
    Properties and Processes. Geoderma, special issue, 116:No 1-2. 2003

4.  Ahuja, L.R., Green, T.R., Erskine, R.H., Ma, L., Ascough II, J.C.,
    Dunn, G.H., Shaffer, M.J., and Martinez, A. Topographic analysis,
    scaling, and models to evaluate spatial/temporal variability of
    landscape processes and management, pp.265-272. In Ahuja, L.R., Ma,
    L., and Howell, T.A. (eds.) Agricultural System Models in Field
    Research and Technology Transfer, CRC Press, Boca Raton, FL. 341 pp.
    2002. 

5.  Ahuja, L.R., Ma, L., and Howell, T.A. (eds.) Agricultural System
    Models in Field Research and Technology Transfer. pp.119-148. CRC
    Press. Boca Raton, FL. 2002.

6.  Ahuja, L.R., Ma, L., and Howell, T.A. Whole system integration and
    modeling: Essential to agricultural science and technology in the
    21^st^ century, pp. 1- 7. In Ahuja, L.R., Ma, L., and Howell, T.A.
    (eds.) Agricultural System Models in Field Research and Technology
    Transfer. CRC Press. Boca Raton, FL. 341 pp 2002.

7.  Ahuja, L.R., Ma, L., Andales, A.A., and Saseendran, S.A.
    Agricultural system models in field research and technology
    transfer. Full chapter in Proc. Second International Agronomy
    Congress. Punjab Sing, I. P. S. Ahlawat, and R. c. gautam (eds.).
    Indian Soc. Agronomy. July, 2004. 226-233. 2004. 

8.  Archer, D.W. Weeding Out Economic Impacts of Farm Decisions. In:
    Hatfield, J.L., Editor. the Farmer\'s Decision. Ankeny, IA: Soil and
    Water Conservation Society. P. 63-75. 2005. (Book chapter)

9.  Ascough II, J.C., Shaffer, M.J., Hoag, D.L., McMaster, G.S., Ahuja,
    L.R., and Weltz, M.A. GPFARM: An integrated decision support system
    for sustainable Great Plains agriculture. In: Stott, D.E., Mohtar,
    R.H., and Steinhardt, G.C. (Eds.), Sustaining the Global Farm --
    Local Action for Land Leadership: Selected papers from the 10^th^
    International Soil Conservation Organization (ISCO) Conference, May
    24-29, 1999, Purdue University, West Lafayette, Indiana.
    International Soil Conservation Organization in cooperation with the
    USDA and Purdue University, West Lafayette, Indiana. p.951-960.
    [http://topsoil.nserl]{.underline}.purdue.edu/nserlweb/isco99/pdf/ISCOdisc/SustainingTheGlobalFarm/P039-Ascough.pdf
    . 2002.

10. Bittman, S., Hunt, D.E., and Shaffer, M.J. NLOS (NLEAP On STELLA^®^)
    A Nitrogen cycling model with a graphical interface: implications
    for model developers and users, Chapter 11, pp. 383-402. In
    Shaffer, M. J., Ma, L., and Hansen, S. (eds.) Modeling Carbon and
    Nitrogen Dynamics for Soil Management, CRC Press, Boca Raton,
    FL. 651. pp. 2001.

11. Boggess, J.E., Xintong, B., and Sassenrath, G.F. Detecting errors in
    cotton grading data using back-propagation neural networks. *In*
    Dagli, C.H., Buxazk, A.L., Enke, D.L., Embrechts, M.J., and Ersoy,
    O., (eds.) Smart Engineering System Design: Neural Networks, Fuzzy
    Logic, Evolutionary Programming, Complex Systems and Artificial
    Life. Intelligent Engineering Systems Through Artificial Neural
    Networks, Volume 14. New York, NY: ASME Press. p. 621-626. 2004.

12. Flanagan, D.C., Ascough II, J.C., Nearing, M.A., and Laflen, J.M.
    The Water Erosion Prediction Project (WEPP) model, Chapter 7, pp.
    145-199. In: Harmon, R.S. and Doe III, W.W. (Eds.), Landscape
    Erosion and Evolution Modeling. Kluwer Academic/Plenum Publishers,
    New York, NY. 713 pp. 2001.

13. Hatfield, J.L., J.H. Prueger, and W.P. Kustas. 2004. Remote sensing
    of dryland crops. *In* S.L. Ustin (ed.) Remote Sensing for Natural
    Resource Management and Environmental Monitoring, Manual of Remote
    Sensing 3^rd^ Edition, John Wiley , Hoboken, NJ Volume 4, Chapter
    10, pp.531-568.

14. Jackson-Smith, D., Powell, J.M., McCrory, D.F,. and Saam, H..
    Understanding manure management behavior on Wisconsin dairy farms:
    lessons from recent on-farm research. Paper 57. Proceedings for the
    State of the Science - Animal Manure and Waste Management Symposium,
    San Antonio, Texas on January 5-7, 2005.
    http://www.cals.ncsu.edu/waste_mgt/natlcenter/sanantonio/proceedings.htm.
    2005.

15. Ma, L. and Shaffer, M.J. Review of carbon and nitrogen processes in
    nine U.S. soil nitrogen dynamics models, Chapter 4, pp. 55-102. In:
    Shaffer, M. J., Ma, L., and Hansen, S. (eds.) Modeling Carbon and
    Nitrogen Dynamics for Soil Management, CRC Press, Boca Raton, FL.
    651pp. 2001.

16. Ma, L., Nielsen, D.C., Ahuja, L.R., Kiniry, J.R., Hanson, J.D., and
    Hoogenboom, G. An evaluation of RZWQM, CROPGRO, and CERES-maize for
    responses to water stress in the Central Great Plains of the U.S.
    In: Ahuja, L.R., Ma, L., and Howell, T.A. (eds.) Agricultural System
    Models in Field Research and Technology Transfer. pp.119-148. CRC
    Press. Boca Raton, FL. 2002.

17. Ma, L., Shaffer, M.J., and Ahuja, L.R. Application of RZWQM for soil
    nitrogen management, Chapter 7, pp. 265-301. In Shaffer, M. J., Ma,
    L., and Hansen, S. (eds.) Modeling Carbon and Nitrogen Dynamics for
    Soil Management, CRC Press, Boca Raton, FL. 651pp. 2001.

18. Pikul, Jr., J.L., J.M.F. Johnson, S.E. Wright, T.C. Caesar TonThat,
    and M.M. Ellsbury. Soil organic matter and aggregate stability
    affected by tillage, pp. 243-258. In: Humic Substances: Moledular
    details and applications in land and water conservation, E.A.
    Ghabbour and G. Davies (eds.). Taylor and Francis, Inc., NY. 2005.

19. Powell, J.M. Contributions to society: manure-fertilizer/fuel,
    developed countries. Encycl. Anim. Sci. (1) 254-257. 2005.

20. Powell, J.M. Enhanced use of feed and manure nutrients in animal
    agriculture. Invited paper. In: Visions for Animal Agriculture and
    the Environment. The John M. Airy Beef Cattle Symposium. Iowa Beef
    Center and Iowa State University. January 5-6, 2006. Kansas City MO.
    [http://www.iowabeefcenter.org/content/Airy/POWELL%20Abstract.pdf](http://www.iowabeefcenter.org/content/Airy/POWELL Abstract.pdf).
    2006.

21. Powell, J.M.. and Kelling, K.A. ^15^N labeling and use of dairy
    manure components for N cycling studies. p. 217-218. In. Controlling
    nitrogen flows and losses. D.J. Hatch, D.R Chadwick, S.C. Jarvis and
    J.A. Roker. Wageningen Academic Publishers. 2004.

22. Read, J.J., E.L. Whatley, L. Tarpley, and K.R. Reddy. Evaluation of
    a hand-held radiometer for field determination of nitrogen status in
    cotton. p. 171-189. In: T. VanToal and L. Tarpley (ed) Digital
    imaging and Spectral Techniques. Applications to Precision
    Agriculture and Crop Physiology. Special Publication 66.
    ASA-CSSA-SSSA, Madison, WI. 2003.

23. Roberts, D.P., Abdul-Baki, A.A. Zasada, I.A. Meyer, S.L.F. and
    Klassen, W. Biologically-based technologies for suppression of
    soilborne pathogens of vegetables. In Pandalai, S.G. (Ed.) Recent
    Research Developments in Applied Microbiology and Biochemistry.
    2005.

24. Sainju, U.M. Cover crops for sustaining vegetable production,
    improving soil and water quality, and controlling weeds and pests.
    In: R. Dris (ed.) Vegetables: Growing environment and mineral
    nutrition. W.F.L. Publishers. In press. 2006.

25. Sainju, U.M. and R. Dris. Sustainable production of tomato. In: R.
    Dris (ed.), "Crops: Growth, quality, and biotechnology", W.F.L.
    Publishers. 2006.

26. Sainju, U.M. and R. Dris. 2006. Sustainable production of tomato.
    In R. Dris (ed.) "Crops: Growth, quality, and biotechnology", W.F.L.
    Publishers. Accepted on October 3, 2005.

27. Sassenrath, G.F., Alarcon, V.J., and Pringle, H.C. Synthetic imagery
    of cotton crops: Scaling from leaf to full canopy, pp. 111-133.
    *In* T. Van Toai, ed. Digital Imaging and Spectral Techniques:
    Application to Precision Agriculture. American Society of Agronomy
    Special Publication No. 66. pp. 253. 2003.

28. Satter, L.D., Klopfenstein, T.J., Erickson, G.E., and Powell, J.M.
    Phosphorus and dairy-beef nutrition. P. 587-606. In A.N. Sharply,
    and J. T. Sims (ed.). Phosphorus Agriculture and the Environment.
    ASA-CSSA-SSSA Monograph N. 46. ASA-CSSA-SSSA, Madison, Wisconsin.
    2005.

29. Selim, H.M. and Ma, L. Modeling nonlinear kinetic behavior of Copper
    adsorption-desorption in soil. In: Selim, H. M. and Sparks, D. L.
    (eds.). Physical and Chemical Processes of Water and Solute
    Transport/Retention in

30. -+ Soil. SSSA Special Publication No. 56. pp. 189-212. Madison, WI.
    2001.

31. Shaffer, M. J. and Ma, L. Carbon and nitrogen dynamics in upland
    soils, Chapter 2, pp. 11-26. In: Shaffer, M. J., Ma, L., and
    Hansen, S. (eds.) Modeling Carbon and Nitrogen Dynamics for Soil
    Management, CRC Press, Boca Raton, FL. 651pp. 2001.

32. Shaffer, M. J., Ma, L., and Hansen, S. (Eds.) Modeling Carbon and
    Nitrogen Dynamics for Soil Management. CRC Press. Boca Raton, FL.
    651pp. 2001.

33. Shaffer, M.J. and Delgado, J.A. Field techniques for modeling
    nitrogen management. Chapter 15, pp 391-411. In: Follett, R.F. and
    Hatfield, J.L. (eds.) Nitrogen in the Environment: Sources,
    Problems, and Management, Elsevier Science B.V. 2001.

34. Shaffer, M.J., Lasnik, K., Ou, X., and Flynn, R. Nleap internet
    tools for estimating NO~3~-N leaching and N~2~-O emissions. Chapter
    12, pp 403-426. In Shaffer, M. J., Ma, L., and Hansen, S. (eds.)
    Modeling Carbon and Nitrogen Dynamics for Soil Management, CRC
    Press, Boca Raton, FL. 651pp. 2001.

35. Tarpley, L. and Sassenrath, G.F. 2003. Environmental and
    physiological components of the cotton leaf reflectance spectrum,
    pp.95-109. *In* T. Van Toai, ed. Digital Imaging and Spectral
    Techniques: Application to Precision Agriculture. American Society
    of Agronomy Special Publication No. 66. pp. 253. 2003.

36. Timlin, D.J., Ya. Pachepsky, F.D. Whisler, and V.R. Reddy.
    Experience with on farm applications of GLYCIM/GUICS. p. 55-69. In.
    L.R. Ahuja, L. Ma, and T.A. Howell (ed.) Agricultural System Models
    in Field Research and Technology Transfer. 2002

[]{#__RefHeading___Toc147540396 .anchor}**LOCATIONS**:

**Ames, IA**:

Small grain cover crops reduce the need for herbicide
applications.........................23

Sensing technology for improved soil compaction
measurements........................\....32

Crop damage assessment tool for field-scale
decisions........................................39

**Auburn, AL\***

Expansion of conservation systems research project leads to technology
transfer
initiatives.............................................................................................14

Effect of landscape position on crop yield when transitioning from
conventional to conservation tillage
systems.......................................................................14

Increasing Adoption of Conservation Tillage Technology in the Tennessee
Valley
Region................................................................................................18

Cover crop roller technology may be a key component of conservation
systems..........21

Mapping soil compaction to identify field areas for precision
tillage.....................\...31

Integrated crop--livestock production systems for the southeastern
U.S..................\...34

Tillage requirements for winter-annual grazing
rotations.....................................34

Improved understanding of disease management in organic potato systems
helps all
producers..............................................................................\...\...\...\...\...\.....45

**Beltsville, MD**

Cover crop-based production system may be a potential alternative to
methyl
bromide...............................................................................................20

Cover crops enhance date
production............................................................21

Discovering the molecular mechanisms that cover crops influence in
production
systems.............................................................................................\...22

Soil maps guide soil sampling for microbial
properties.......................................31

The latest scientific knowledge and technology incorporated into GOSSYM
and
GLYCIM..........................................................................................\....43

Generic interface for crop simulation models simplifies model use for
growers and
scientists..............................................................................................43

Improved understanding of disease management in organic potato systems
helps all
producers..............................................................................\...\...\...\...\...\.....45

Organic management practices and soil biological
responses.....................\...\...\...\...\...45

Increasing crop rotation length and complexity reduces weed pressure and
increases crop yields in organic
systems........................................................................\...45

Modified crops for use in organic production
systems.........................................47

High tunnel research capacity established to serve mid-Atlantic small
farmers....................................................................................\...\...\...\...\...50

Crop simulation for decision making in Pacific Northwest potato-based
cropping
systems.............................................................................................\...50

GLYCIM model increases irrigation efficiency for Mississippi Delta
soybean
growers.............................................................................................\...42

**Booneville, AR**

Organic alternatives for deworming sheep and
goats..........................................45

Organic log-grown shiitake mushrooms contain health-promoting
polysaccharides......................................................................................48

Important criteria defined for the design and management of temperate
silvopasture
practices..............................................................................................49

Eastern red cedar and chestnuts are attractive alternative crops for
small
farmers.............................................................................................\...50

Small-Scale Farmers Can Receive Income from Pine Straw Without
Increasing Soil
Erosion.............................................................................................\...50

Management schemes for alley cropping practices improve dove
habitat..................53

**Brookings, SD**

Diversifying crop rotations and reducing tillage can reduce risk to
Northern Corn Belt
farmers.............................................................................................\...19

Reducing tillage and diversifying crop rotations can reduce risk to
Northern Corn Belt
farmers.............................................................................................\...38

**Columbia, MO**

Alley cropping of alfalfa reduces need for insecticides, thus increasing
profitability
potential...............................................................................................27

Sub-field management zones for improved crop nutrient
utilization........................30

Mapping soil electrical conductivity to understand sub-field grain
production
variability..........................................................................................\...31

Sensing technology to improve nitrogen application
accuracy...............................32

Sensing technology for improved soil compaction
measurements...........................32

Sensing to improve nitrogen application
accuracy.............................................32

Understanding within-field grain yield
variability.............................................33

**Corvallis, OR**

Conservation practices improve soil, air, & water quality and increase
profits in perennial grass seed production
systems.....................................................................15

Interactive decision aid developed to estimate stem rust disease
development.............41

How and why weeds differ between fields and among
years.................................42

Web-based planning tools for conservation
managers.........................................44

Technology development for farm--scale conversion of straw to
energy....................49

Use of remote sensing and ground-truth surveys to monitor soil
disturbance and land use patterns across
landscapes...................................................\...\...\...\...\...\...\...\...\.....51

Identifying management practices that optimize economic and
environmental benefits at the watershed scale
level...........................................................................51

Grass seed farming landscapes provide excellent fish and wildlife
habitat......\...\...\...\...\...53

**Dawson, GA**

Decision support systems for irrigation scheduling in peanuts, corn, and
cotton to improve profits and
adoption......................................................................28

The economics of crop rotation sequences and technology transfer to
producers..................................................................................\...\...\...\...\...40

Reduced supplemental irrigation in three Southeastern conservation
tillage
systems.............................................................................................\...29

**Florence, SC\***

Conservation tillage with a rye cover crop reduces thrips populations in
Southeast USA
cotton.............................................................................................\...\...27

Understanding within-field grain yield
variability.............................................33

**Fort Collins, CO**

No-tillage allows more intensive and flexible dryland cropping systems
and improves soil
quality................................................................................................15

On-farm research results in simple spreadsheet planning
tools...............................40

Decision aids provide guidance to improve production efficiency,
reducing input costs, and increase
profitability...............................................................................\............41

The latest scientific knowledge and technology incorporated into GOSSYM
and
GLYCIM.............................................................................................42

Agricultural system-level models used to help direct field
research.........................43

Mapping soil electrical conductivity to understand sub-field grain
production
variability.............................................................................................31

**Lane, OK\***

Factors of organic production affect cover crops and
vegetables.............................47

**Mandan, ND\***

Dynamic systems approach to rotation crop
selection.......................................\...19

Producers can evaluate the 100 different crop sequences for the Northern
Great
Plains..................................................................................................41

Integrating annual forages into a Great Plains beef production
system................................................................................................36

**Madison, WI**

Tannins may increase dairy profits and enhance environmental
quality.....................36

Integrating annual forages into a Great Plains beef production
system...........\...\...\...\...\...36

Dairy herd management enhances nutrient
cycling.............................................36

On-farm research improves nutrient management on dairy
farms............................37

Refined dairy diets enhance profits and the
environment......................................37

Improved understanding of disease management in organic potato systems
helps all
producers...........................................................................................\...44

Improved pasture utilization increases dairy cow feed
efficiency............................35

**Mississippi State, MS**

GLYCIM model increases irrigation efficiency for Mississippi Delta
soybean
growers..................................................................\..............................42

The latest scientific knowledge and technology incorporated into GOSSYM
and
GLYCIM.............................................................................................43

Generic interface for crop simulation models simplifies model use for
growers and
scientists..............................................................................................43

Experimental designs for large commercial field precision
applications....................33

**Morris, MN**

Diversifying crop rotations and reducing tillage can reduce risk to
Northern Corn Belt
farmers....................................................................................\............19

Reducing tillage and diversifying crop rotations can reduce risk to
Northern Corn Belt
farmers................................................................................................38

Holistic approach to farm planning and conservation programs improves
profitability and enhances natural resources
conservation.........................................................39

Decision aids provide guidance to improve production efficiency,
reducing input costs, and increase
profitability...........................................................................41

Cuphea as a new oilseed crop for Northern Corn
Belt.........................................50

**Orono, ME**

Research results used to identify profitable combinations of potato
cropping practices for the Northeastern
U.S................................................................................39

Manure use can be managed to benefit soil biodiversity and reduce
potential health
risks...................................................................................................44

Improved understanding of disease management in organic potato systems
helps all
producers..........................................................................................\....45

Many approaches used together can increase New England agriculture
profitability...\...25

**Prosser, WA**

Reduced tillage in potato production
systems................................................\...16

Utilizing fall-planted cover crops for weed suppression in potato
production
systems................................................................................................20

Cropping practices and rotations reduce the negative impact of weeds in
potato production
systems..................................................................................23

Management strategies in rotation crops reduce populations of volunteer
potato..........24

Nitrogen and irrigation best management practices for potatoes on coarse
textured
soils...................................................................................................29

Crop simulation for decision making in Pacific Northwest potato-based
cropping
systems................................................................................................40

The latest scientific knowledge and technology incorporated into GOSSYM
and
GLYCIM.............................................................................................43

Sustainable production of bio-fuel
crops.........................................................48

**Pullman, WA**

Regional efforts to reduce weed pressures in the Pacific
Northwest.........................23

Integrated management strategies reduce jointed goatgrass in the Pacific
Northwest...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\.....24

No-till spring cropping system decreases downey brome
populations.......................25

Development of Site-Specific N Indices for Precision N
Management.....................34

First Low-Soil Disturbance Organic Cropping System Designed and Tested
in Pacific
Northwest.............................................................................................46

**Salinas, CA**

Evaluation of novel cover
crops..................................................................21

Development of a biointegrated production system for strawberries
eliminates the need for
fumigation.......................................................................................25

Organic management practices and soil biological
responses.....................\...\...\...\...\...45

Cover cropping practices improve organic weed
management...............................46

Stale seed bed techniques for organic vegetable
production..................................47

**Stoneville, MS**

Conservation tillage and cover crop benefits for cotton and
soybeans.......................17

Optimization of crop performance through the proper water resource
management......27

Development of tools to rapidly assess crop
status..........................................\...30

Experimental designs for large commercial field precision
applications....................33

**Sidney, MT**

Development of a PCR protocol for rapid detection of Cercospora
beticola\...\...\...\...\...\.....26

Developing a strip tillage system for small seeded
crops.................................\...\...16

Safflower is a secondary host of Cercospora
beticola....................................\......26

Feedback sensor systems for real time water management and
self-propelled irrigation system decision
support............................................................................28

Designing low-risk dryland cropping systems for the Northern Great
Plains..................................................................................................38

**Watkinsville, GA**

Systems approach improves adoption of conservation tillage systems in
the Southeastern U.S.
...................................................................................................17

Integrated crop--livestock production systems for the southeastern
U.S.....................34

Tillage requirements for winter-annual grazing
rotations.....................................34

Modified hay production system improves ruminant feed
intake............................35

The economics of crop rotation sequences and technology transfer to
producers.............................................................................................40

Expansion of conservation systems research project leads to technology
transfer
initiatives.............................................................................................14

Effect of landscape position on crop yield when transitioning from
conventional to conservation tillage
systems.......................................................................14

Cover crop roller technology may be a key component of conservation
systems.............................................................................................\...21

Mapping soil compaction to identify field areas for precision
tillage........................31

**Weslaco, TX**

Conservation tillage systems for hot and dry
climates.........................................18