2007 ANNUAL REPORT 

NATIONAL PROGRAM - 216 

AGRICULTURAL SYSTEM COMPETITIVENESS AND SUSTAINABILITY 

American farms generate more than $200 billion in goods and services on 442 million 

acres. Profitable farms are also the basis of vibrant rural economies. Consumers benefit 

from agricultural production that provides an abundant choice of products at relatively 

low costs. However, many farms are suffering from commodity prices that have remained 

relatively unchanged for decades, while the costs of fuel and other purchased inputs 

continue to rise. In addition, there is increasing competition from overseas markets where 

production costs are comparatively low. At the same time, continued advancement of 

conservation goals is needed to enhance the natural resource base upon which the nation 

not only depends for food, feed, fiber, and renewable energy, but also for abundant and 

high quality supplies of fresh water, clean air, and healthy ecosystems. The challenges 

producers face regarding productivity, profitability, and natural resource stewardship are 

complex, so solutions to these challenges are equally complex. 

The USDA-ARS projects contributing to National Program Agricultural System 

Competitiveness and Sustainability (NP 216) use an interdisciplinary systems research 

approach to bring together the diverse expertise needed to understand how different kinds 

and sizes of farms function, and how changing or introducing new technology will affect 

their economic and environmental sustainability. Whether the ARS teams of scientists 

and their university and industry cooperators are in the Pacific Northwest, Southwest, 

Great Plains, Midwest, Southeast, or New England, they use their collective scientific 

talent to find the best combinations of practices to help producers achieve their 

production goals. 

NP 216 Agricultural System Competitiveness and Sustainability contributes to USDAARS Strategic Plan Goal 2: Enhance the Competitiveness and Sustainability of Rural and 

Farm Economies, Objective 2.1: Expand domestic market opportunities, and Objective 

2.2: Increase the efficiency of domestic agricultural production and marketing systems; 

and Strategic Plan Goal 6: Protect and Enhance the Nation’s Natural Resource Base and 

Environment.

AGRONOMIC CROP PRODUCTION SYSTEMS 

The Agronomic Crop Production Systems component addresses challenges in 

agricultural systems dominated by the commodities including corn, soybean, cotton, 

peanut, wheat, barley, and turf and herbage seed crops. The value of U.S. crop output in 

2002 was 2.6 times higher than that in 1948, while the inputs required to achieve this 

output have declined. However, the profitability of many farms producing major 

commodity crops is declining because of escalating costs of energy, fertilizers, and other 

purchased inputs. Research is needed to develop production strategies and technologies 

that increase productivity and reduce production costs and risks of economic loss, all 

while maintaining or even enhancing natural resource quality. 

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In addition, the United States has embarked on an ambitious program to replace a 

significant portion of petroleum-based transportation fuels with bio-based fuels from 

agricultural sources. Producers, government agencies, energy companies, and policy 

makers need to know how best to produce biomass and dedicated energy crops in 

different agricultural regions of the country and what the likely impacts would be of an 

expanding bio-economy on whole-farm economic return and natural resource quality. A 

new generation of production systems and technologies is needed to produce feedstocks 

sustainably to support emerging bioeconomies in ways that do not disrupt the integrity of 

existing farms and markets or degrade the quality of natural resources. 

Montana Dryland Cereal Producers Can Increase Profits by Considering Reduced 

Tillage and Optimal Cropping Sequences. Scientists at the Northern Plains 

Agricultural Research Laboratory in Sidney, Montana have reported results from a 21-

year study of the effects of tillage method and cropping sequence for cereal production. 

Even though less wheat was produced each year with the annual crop system, total 

income over the two years was greater than for one crop produced every other year. Mean 

crop biomass was 53 to 66% greater with reduced tillage with an annual cropping system 

than for conventional till with a spring wheat followed by a fallow system. During a sixyear drought period during this long-term study, zero-tillage management allowed greater 

soil water to be available at planting than with conventional tillage. Just as importantly, 

the amounts of carbon and nitrogen in the soil surface residues were 23 to 141% greater 

than in the conventional tillage system. These findings demonstrate both the yield and 

conservation benefits of using reduced tillage practices in the Northern Great Plains 

region, and provide the scientific basis to support participation in USDA Farm Bill 

Conservation Title programs. 

Using Cover Crops Enhances Conservation Management Benefits. Cover crops 

provide the additional carbon needed to gain the full benefits from using conservation 

cropping systems in most regions. Successful adoption of cover crop use in conservation 

tillage systems requires knowledge of establishment methods, types of cover crop, 

fertilizer management, and termination equipment. USDA-ARS scientists from the 

National Soil Dynamics Laboratory in Auburn, Alabama and the J. Phil Campbell Sr. 

Natural Resource Conservation Center in Watkinsville, Georgia, in conjunction with 

other regional experts synthesized diverse information on managing cover crops in 

conservation systems to produce a comprehensive guideline titled Managing Cover 

Crops Profitably. Both general recommendations, as well as specific considerations for 

different regions of the United States are presented. The compiled information is being 

adopted by university extension agents in training programs to help producers incorporate 

cover crops into farm operations and USDA-NRCS to develop conservation plans for 

delivery of Farm Bill Conservation Title programs in the Southeastern region. 

Autumn-Applied Nitrogen Fertilizer is Needed for Optimal Winter Grass Cover 

Crop Growth. Scientists at the National Soil Dynamics Laboratory in Auburn, Alabama 

previously showed that to maximize winter cover crop biomass, supplemental sources of 

nitrogen are needed. However, it was not know whether residues from summer-grown 

peanuts could supply a portion of the nitrogen requirements for these winter cover crops. 

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This study assessed the nitrogen contribution of peanut residue to a rye winter cover crop 

in a conservation management system. Peanut residues did not enhance cereal rye 

biomass yields, but additional autumn-applied nitrogen increased the amounts of cereal 

rye biomass produced. Although growers should still be encouraged to leave peanut 

residue in the field, recommended nitrogen rates for winter annual grass cover crops 

should not be reduced. This kind of practical information is needed so growers can make 

science-based decisions when looking for the best nutrient management options for their 

farms in the Southeastern Coastal Plains region. 

Barriers Identified That Keep Midwestern Growers from Using Cover Crops. Even 

as the benefits of cover crops continue to be reported, it is not known how many farmers 

are actually using cover crops, and what keeps more from doing so. ARS scientists at the 

National Soil Tilth Laboratory in Ames, Iowa are working with collaborators at Iowa 

State University to find out how many farmers in the Corn Belt use cover crops in their 

production systems. It was found that farmers who grow a greater diversity of crops were 

more likely to use cover crops, but only 18 percent of farmers in the region reported ever 

using cover crops — only 8 percent had planted cover crops in the fall of 2005. Eighty 

percent of farmers use some other sort of conservation practices, and indicated that they 

believed that cover crops improve soil conditions by reducing erosion and increasing soil 

organic matter. However, over a quarter of farmers perceived that cover crops are too 

expensive to use, and over a third believed that planting cover crops took too much time. 

These findings will help researchers design their work to demonstrate the maximum 

combined benefits from using cover crops to Midwest farmers and help them realize 

ways to maximize profits. 

Conservation Tillage Offers Significant Water Savings for Southeastern Region. The 

long-running water rights negotiations among Alabama, Florida and Georgia focus on 

diminishing water resources, but ignore the potential water savings offered by 

conservation tillage adoption in the region. USDA-ARS research scientists from the 

Southeast Watershed Research Unit in Tifton, Georgia and J. Phil Campbell, Sr., Natural 

Resource Conservation Center in Watkinsville, Georgia used county-level crop, tillage, 

and soil information to show that conservation tillage currently reduces agricultural 

irrigation water requirements by as much as 12%. Increasing conservation tillage to 40% 

in counties where conservation tillage adoption rates were below the 41% national 

average increased water savings 10% statewide which is equivalent to 13.7 billion 

gallons – the equivalent local savings of 0.2 to 6.0 years of water use. These findings 

provide guidance for policy makers to help resolve the needs for water and manage its 

use by agriculture and urban populations in the Southeastern U.S. 

Integrated Conservation Management Practices Combined with Subsoiling Not 

Only Mitigate Compaction, But Also Reduce Fuel Use. Compaction limits the 

productivity of most Southern United States soils, so farmers typically use periodic inrow subsoiling to loosen compacted soil layers to promote root growth and increase crop 

yields. However, the cost of this operation has become increasingly expensive with 

rapidly escalating fuel prices. USDA-ARS scientists at the National Soil Dynamics 

Laboratory in Auburn, Alabama have shown that fuel use can be reduced 54% when 

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subsoiling by proper selection of bentleg subsoiler shanks used at shallow tillage depth, 

operating at the proper soil moisture condition, using cover crops, and controlling vehicle 

traffic. An additional benefit was minimal disruption on the soil surface of the crop 

residues that help intercept precipitation and prevent soil erosion. All of these practices in 

combination are an integrated approach for conservation management in Southeastern 

mixed crop production systems. 

Integrating Cover Crops with Conservation Tillage Practices Can Reduce Cotton 

Production Costs. Scientists from the J. Phil Campbell, Sr., Natural Resource 

Conservation Center, in Watkinsville, Georgia along with cooperators from the 

University of Georgia and Monsanto Inc. compared seven kinds of cover crops for use in 

cotton production on a Coastal Plain soil with strip tillage and no-till conservation 

practices. The legumes hairy vetch and Austrian winter pea fixed about half the amount 

of nitrogen needed to grow a cotton crop, while the combination of black oat and striptillage provided an additional $20 to $30 per acre returns than a cereal rye cover crop 

alone. Using nitrogen fixing cover crops to replace purchased nitrogen adds to the 

savings from conservation tillage practices, and enhances soil quality that contributes to 

increased crop productivity. Combined, these practices can increase returns to Coastal 

Plain producers where a majority of the 2.9-million acres of cotton in the southeastern 

U.S. is grown. 

Conservation Tillage Can Increase the Economic Sustainability of Mississippi Delta 

Cotton Production Systems. Concern about increasing costs of production and the need 

to protect soil and water resources has led many Mississippi Delta cotton producers to 

consider various conservation practices, including reduced tillage and cover crops. 

However, the economic impacts of these practices are not known. USDA-ARS scientists 

at the Application and Production Technology Research Unit in Stoneville, Mississippi in 

collaboration with Mississippi State University scientists and producers demonstrated 

that the highest returns and lowest relative risks on Delta alluvial soils would be obtained 

by using a traditional no-till production system. Additional use of cover crops or subsoiling as a part of the management package increased yield sufficiently to offset the 

additional expenses associated with these practices. Conventional production practices, 

while giving relatively high returns, were also the riskiest compared to conservation 

tillage management. These results are of particular importance in designing more 

economically and environmentally sustainable cotton production systems for the MidSouth region where growers are highly dependent upon USDA Farm Bill programs for 

financial success. 

No-till Irrigated Corn May Yield Less with No-till Establishment, but Economic 

Returns are Greater than with Conventional Tillage. Conversion of irrigated 

conventional tilled cropland to no-tillage establishment could provide a number of 

environmental benefits, but the economics of production are not known. Scientists at the 

Northern Great Plains Research Laboratory in Mandan, North Dakota and the Soil Plant 

Research Unit in Fort Collins, Colorado investigated costs and returns for conventional 

tillage and no-till irrigated continuous corn production in Northeastern Colorado. Even 

though corn yields were lower under no-till than under conventional tillage, production 

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costs were reduced so much that profits were greater for the no-till establishment system. 

This research provides farmers with economic analysis information that is needed to 

assure them that yield losses due to switching to no-tillage irrigated corn production will 

be offset by greater profits. Adoption of a no-tillage conservation management system 

should also lead to reduced soil erosion and fuel consumption, increased soil carbon 

sequestration, and lowered greenhouse gas emissions. 

No Evidence Found of “Tough Bt” Corn Residues. There is widespread anecdotal 

information within the agricultural community that residues from some genetically 

modified (GM) corn hybrids may be resistant to degradation. As a result, implement 

manufacturers are now marketing alternative tillage machinery to deal specifically with 

“tough Bt” corn residue. USDA-ARS scientists at the North Central Agricultural 

Research Laboratory in Bookings, South Dakota evaluated the field decomposition rates 

of residues from Bt and non-Bt corn hybrids over a period of 22 months. No differences 

in the decomposition rates of the chopped residue from the four corn hybrids were 

detected. Additional studies are underway to determine alternate explanations for the 

perceived toughness of Bt-containing corn residues. Widespread adoption of unnecessary aggressive tillage would offset decades of gains in soil and water quality 

improvement that has been achieved through conservation tillage practices. This research 

is critical with greater amounts of corn being planted to meet the increasing demand for 

fuel ethanol. 

Critical Soil Biology Functions Impacted by Genetically Modified (GM) Soybean 

Production. Genetically modified Roundup-resistantTM soybeans are planted on over 

90% of soybean acreage in the U.S. However, a full assessment of the impacts of this 

technology on whole systems has not been conducted. Scientists at the Cropping Systems 

and Water Management Research Unit in Columbia, Missouri have determined the 

effects of GM Roundup-resistant soybean treated with Roundup herbicide on crop 

residue decomposition and soil biological processes under variable soil moisture 

conditions. Most of the measurements, including decomposition, showed no effect from 

Roundup or GM soybean at any soil moisture. However, the Fusarium fungal group 

consistently infected soybean roots at a higher incidence at all soil moisture levels in 

fields receiving Roundup, than with no Roundup applied. Results indicate that general 

biological measures such as residue decomposition did not detect GM soybean effects, 

but Fusarium microbial groups were more sensitive indicators of effects. This 

information is important because it helps to understand the occasional production 

problems observed in production system using GM soybeans, and to develop 

management solutions that will avoid crop growth reductions when GM soybean are 

included as a part of the management package. 

Sustainable Straw Amounts Available for Biofuel Production are Estimated for the 

Pacific Northwest. Straw produced during cereal and grass seed production in Oregon, 

Washington, and Idaho represents a potentially significant feedstock, but the amount and 

location of straw in excess of that required for conservation purposes was not known. 

Scientists at the USDA-ARS Forage Seed and Cereal Research Unit in Corvallis, Oregon 

determined total straw production for all counties in these three states and determined 

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county-by-county amounts of straw that should be returned to the soil for conservation 

purposes. A geographic information systems resource map was developed showing where 

the 7 million tons of straw that are annually produced in the region can be harvested. This 

information is useful to farmers and biofuel-producing companies who are beginning to 

consider the best strategies for utilizing this resource, and to government agencies for 

developing the best policies to ensure that high quality soil and water resources are 

maintained. 

Nutrient Replacement Needs Determined for Irrigated Switchgrass Production in 

the Inland Pacific Northwest. Perennial herbaceous bioenergy crops have the potential 

to sequester soil carbon, supply a portion of U.S. energy needs, and reduce atmospheric 

CO2 enrichment when used as a fuel. Scientists at the USDA-ARS Vegetable and Forage 

Crop Research Unit in Prosser, Washington have determined the amounts of essential 

plant nutrients that will be exported from farms with harvested biomass to determine 

reductions in soil fertility and how these will impact fertilizer recommendations for 

irrigated farms in the Inland Pacific Northwest. Harvested switchgrass biomass yields 

averaged 22 metric tons per hectare per year, and would produce 7,500 liters of ethanol. 

For every dry ton of switchgrass harvested, 25 lbs of nitrogen, 3.2 lbs of phosphorus, and 27.1 

lbs of potassium are removed from the field. Bioenergy crop producers can use this information 

to adjust fertilization rates to meet their feedstock production goals and to ensure that 

adequate nutrients are available for subsequent crops grown in rotation. In addition, these 

data can be used in the development of secondary markets, such as carbon credit trading 

or by ethanol producers interested in nutrient recovery for production of fertilizer or 

animal feed supplements. 

SPECIALTY CROP AND ORGANIC PRODUCTION SYSTEMS 

The Specialty Crop and Organic Production Systems component is focused on solving 

problems related to the production of high-value specialty crop and value-added organic 

products. The value of U.S. specialty crops is greater than the combined value of corn, 

soybean, wheat, cotton, and rice crops. At the same time, organic production now 

captures more than 3% of the U.S. food market, and is growing at a rate of 10% annually. 

The production of high-value specialty and organic crops often requires cost-intensive 

practices to achieve profitable production levels of products that must be of sufficient 

quality to meet high market and consumer preference standards. Producers wishing to 

produce high-value specialty and organic crops may face significant barriers to the 

development and marketing of new products. Alternative management strategies are 

needed that utilize an understanding of the agro-ecological and biophysical processes 

innate to plants, soils, invertebrates, and microbes that naturally regulate pest problems 

and soil fertility, to reduce or replace reliance on the use of synthetic pesticide and 

fertilizer production inputs. Also, an understanding of marketing supply chains from 

field-to-table must be considered and integrated with production, handling, and 

processing information to increase the portion of product value received by producers. 

Brassica Green Manure Crops Reduce Soilborne Potato Diseases. Soilborne diseases 

are persistent, recurring problems in potato production and are difficult to control, 

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resulting in reduced plant growth, tuber quality, and yield. Brassica rotation crops and 

green manures have the potential to control multiple soilborne diseases through 

biofumigation and changes in soil microbial communities. USDA-ARS scientists at the 

New England Plant, Soil, and Water Laboratory in Orono, Maine conducted on-farm 

field trials and showed that mustard, canola, and rapeseed green manures reduced 

powdery scab by 15-40%, and canola and rapeseed reduced black scurf by 70-80%. A 

mustard green manure also reduced common scab by 25%. Overall, mustard was most 

effective in reducing powdery and common scab diseases, and rapeseed and canola were 

most effective in reducing Rhizoctonia diseases. This research provides conventional 

potato growers with a viable tool for reducing soilborne disease levels without additional 

pesticides, and is useful to organic producers who do not use synthetic fungicides. 

Cover Cropping Practices Improve Organic Weed Management. USDA-ARS 

scientists at the Crop Improvement and Protection Research Unit in Salinas, California, 

along with university and grower cooperators, showed that different cover crops produce 

similar amounts of biomass, but there are large differences in their weed suppressive 

abilities. At typical seeding rates, weed suppression was excellent by mustard and rye, 

but extremely poor in legume/cereal mixes. Increasing the seeding rate of the 

legume/cereal mixes improved weed suppression to acceptable levels. Also, rotary hoe 

use can reduce weed seed production in winter cover crops by up to 80%, so weeds are 

less of a problem in the spring. 

Purple Bounty Hairy Vetch Variety Released for Cover Crop Use. USDA-ARS 

scientists in the Sustainable Agriculture Systems Laboratory at Beltsville, Maryland in 

cooperation with Pennsylvania State University, the Rodale Institute, and Cornell 

University, released Purple Bounty, a new hairy vetch cultivar that combines the traits of 

early flowering and improved winter survival. Hairy vetch is planted in the fall and, after 

over-wintering, produces abundant biologically fixed nitrogen in the spring that can be 

used to nourish subsequent crops such as corn and tomatoes. The early flowering feature 

of Purple Bounty is an important advantage because it permits earlier planting of the 

subsequent crops. The availability of Purple Bounty should encourage more widespread 

use of this nitrogen-fixing legume cover crop. The initial large-scale seed increase of 

Purple Bounty was made at Meadville, Pennsylvania. 

Fresh-Market Onion Production is Aided by Cover Crops. Lack of soil organic 

matter in hot, arid climates limits agricultural production and sustainability. To enhance 

soil organic matter, scientists at the Kika de la Garza Subtropical Agricultural Research 

Center in Weslaco, Texas have used a combination of cowpea and sorghum cover crops 

to increase soil organic matter by 52% and 61%. As a result, yields were increased 60-

80% and there was an increase in the percentage of large market onions. Also, increasing 

soil organic matter improved soil tilth so that it was easier for the onions to be 

mechanically transplanted, with less need for follow-up labor. This achievement is 

important because it demonstrates that improved soil quality can also be translated into 

increased onion yield and quality. These findings are useful to both conventional as well 

as organic farmers. 

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Bulletin Released Describing Sustainable Production of Fresh-Market Tomatoes 

and Other Vegetables. USDA-ARS scientists in the Sustainable Agricultural Systems 

Laboratory at Beltsville, Maryland released U.S. Department of Agriculture, Agricultural 

Research Service, Farmers’ Bulletin 2280 that focuses on the winter annual legume hairy 

vetch, both as a cover crop and mulch in a sustainable tomato production system. As a 

cover, vetch serves to fix nitrogen, recycle nutrients, reduce soil erosion and compaction, 

and add organic matter to the soil. When converted to mulch, the residue reduces weed 

emergence, reduces water loss from the soil, acts as a slow-release fertilizer, and 

suppresses some pathogens and pests. Though research on this mode of production was 

originally confined to growing tomatoes in stands of hairy vetch, further study has shown 

that the underlying concept can be easily modified to suit other crops and regional 

growing conditions. Some direct-seeded vegetables can be grown effectively, as can 

winter vegetables in subtropical climates. Other cover crops can be selected and even 

seeded in beneficial mixtures to suit local growing conditions. 

Limited Sweet Corn Yields Need to be Overcome When Using Legume Cover 

Crops. Legume cover crops can substitute for and reduce fertilizer nitrogen inputs in 

different cropping systems. A three-year field experiment was conducted by USDA-ARS 

scientists in the Sustainable Agricultural Systems Laboratory at Beltsville, Maryland to 

measure the nitrogen released from a hairy vetch cover crop and the efficiency with 

which this nitrogen was used in sweet corn production compared to nitrogen supplied in 

fertilizer. Fewer marketable ears were produced by sweet corn grown on nitrogen 

released from a decomposing hairy vetch cover crop than by corn grown on synthetic 

nitrogen released from fertilizer. The lower crop use efficiency of nitrogen derived from 

hairy vetch cover crops is caused by reduced crop population as a result of interference 

by heavy levels of surface cover crop residue. This research shows the need to find new 

ways to manage legume cover crops to overcome limitations to organic sweet corn 

productivity. 

White Plastic Barriers for Blackberry Weed Control Provide Multiple Benefits. 

Weed pests are a challenge to control in blackberry brambles, particularly when organic 

methods are employed. USDA-ARS researchers at the Integrated Farming and Natural 

Resources Research Unit, Weslaco, Texas found that white plastic weed barriers used to 

control weeds in newly planted brambles not only reduced labor needed for weed control, 

but improved blackberry yields and fruit quality. Improved plant vigor and berry soluble 

solids likely result from more consistent soil temperatures at four inches, while 

maintaining consistent soil moisture amounts. 

Weed Control Costs Reduced for Organic Vegetable Producers. Hand labor for weed 

management in high-value organic vegetable crops can cost up to $1500 per acre. USDAARS scientist at the Crop Improvement and Protection Research Unit in Salinas, 

California and cooperators conducted on-farm research to evaluate the effectiveness and 

costs of six organic 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 

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$1557 per acre. These findings identified effective methods to help organic producers 

minimize the need for hand weeding of high value vegetable crops. 

Combining Biological Amendments with Cultural Practices Improves Potato 

Disease Control and Productivity. Potatoes frequently suffer from numerous soilborne 

diseases that reduce tuber quality and yield. Biological amendments, including biocontrol 

organisms, microbial inoculants, and compost teas, may be used to increase soil 

microbial diversity and antagonism towards soilborne pathogens. In multi-year field 

trials, USDA-ARS scientists at the New England Plant, Soil, and Water Laboratory in 

Orono, Maine showed that a combination of conifer-based compost and biocontrol 

amendments resulted in significant reductions in Rhizoctonia disease (23-48%) and 

improved tuber yield (30-50%). Combining biological amendments with an effective 

crop rotation (barley underseeded with ryegrass) reduced stem canker, black scurf, and 

common scab by 18-33% and increased potato yields by 20-32%. This research shows 

that combining biological and cultural practices can substantially reduce diseases and 

increase yields without additional use of synthetic pesticides. 

Potato Late Blight Infection Comes from a Common Weed. Potato Late Blight caused 

by Phytophthora infestans is a serious worldwide threat to the potato and tomato 

industries. USDA-ARS scientists at the New England Plant, Soil, and Water Laboratory 

in Orono, Maine previously reported the first identification in Maine of P. infestans on 

the common weed hairy nightshade. In 2007, the scientists further evaluated the 

significance of hairy nightshade as an alternate host to potato Late Blight, and found that 

disease severity varied with source of inoculum (9-37%), weed sage-of-growth (6-21%), 

ambient temperature (1-14%), and relative humidity (6-18%). Results from this 

ecological-based pest management research shows that potato growers can reduce their 

risk of potential Late Blight infection by controlling hairy nightshade weed populations, 

and reduces the need for fungicide applications. 

Potato Root-knot Nematode Resistant Genetic Lines Negated by Hairy Nightshade.

Columbia root-knot nematode is a major pest of potato in the Pacific Northwest and is 

controlled by costly soil fumigation. Nematode-resistant potato breeding lines developed 

by USDA-ARS scientists in the Vegetable and Forage Crop Research Unit at Prosser, 

Washington were shown to segregate in response to nematode damage on tubers when 

grown in the presence hairy nightshade. Some lines possessed only root resistance and 

lacked tuber resistance, while other lines possessed both root and tuber resistance. These 

findings demonstrate how weed hosts of root-knot nematodes may negate the positive 

impact of growing resistant potatoes that lack tuber resistance and the importance of 

weed control on managing plant parasitic nematode populations. Commercial potato 

breeders can use this new information to select for both root and tuber resistance in 

breeding materials. 

Feasibility of Organic Grain Production Systems Improved. There is inadequate 

information regarding the performance of organically produced grain crops in the United 

States, especially in Coastal Plain soils of the mid-Atlantic region. USDA-ARS scientists 

at the Sustainable Agricultural Systems Laboratory in Beltsville, Maryland showed in a 

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ten-year study that average corn yields in organic systems increase with increasing crop 

rotation length and increasing diversity of crops grown in rotations. Average corn grain 

yield was 30% greater in a corn-soybean-wheat-hay rotation than in a corn-soybean 

rotation, and 10% greater than in a corn-soybean-wheat rotation. Differences were due to 

increased nitrogen availability and lowered weed competition with increasing crop 

rotation length. This research shows that increasing crop rotation length and complexity 

can address the two most important production challenges in organic grain crop 

production: providing adequate nitrogen for crop growth and decreasing weed 

competition. 

Organic Grain Production Transition Strategies for the Northern Corn Belt Region.

While many environmental benefits are realized from reduced tillage, increasing crop 

diversity, and reducing agricultural chemical use, short-term economic factors often 

encourage farmers to use intensive tillage, high amounts of chemical inputs, and 

specialized crop production. Scientists at the North Central Soil Conservation Research 

Laboratory in Morris, Minnesota compared crop yields and economic costs and returns 

for northern Corn Belt farmers who desire to switch from a conventional corn-soybean 

cropping systems to a range of alternative systems including organic production. Results 

from the research showed that increasing crop diversity and reducing tillage intensity 

generally reduced production costs. Yields were reduced under organic production 

conditions compared to conventional systems, but when considering the overall 

production system costs, many crops under alternative management showed no 

significant differences in net returns, suggesting that there were no economic barriers to 

adopting these practices. Economic returns for most organic systems were comparable or 

exceeded those from conventional production when organic price premiums were 

included. This research provides farmers with information needed to help them decide 

whether to switch to more profitable alternative production systems that include reduced 

tillage intensity, increased crop diversity, and organic production. This research will also 

be an important source of information for policy makers in determining economic 

incentives that may be necessary to encourage producers to adopt these practices. 

INTEGRATED TECHNOLOGY AND INFORMATION SYSTEMS

The Integrated Technology and Information Systems component focuses on research to 

develop and apply technologies that can be used to understand and increase production 

system economic and environmental sustainability. ARS customers want not only the 

latest information and best technology research can provide, but also to know how these 

innovations can best be incorporated into their unique operations. Also important to know 

is whether the use of new technology will increase farmer ability to compete in the 

marketplace or to deliver their services. Understanding the system level impacts of 

implementing new technologies will help increase adoption and reduce uncertainty and 

risk. Recognizing that users are the ultimate system integrators, customer participation in 

the entire research process becomes a necessity for the successful transfer and adoption 

of emerging technologies. 

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“Trigger-on” Indicator for use with Precision Weed Sensing Sprayer Units. A major 

drawback with precision intermittent application spray systems that only spray when 

weeds are present is that no feedback is provided to the operator when each spray unit is 

activated. This limitation makes it difficult to determine if the sensors are functioning 

properly, particularly on wide boom spray units. To overcome this problem, the 

Columbia Plateau Conservation Research Center, Pendleton, Oregon developed a low 

cost trigger-on indicator that provides visual feedback to the operator. The device 

performed reliably over a 150-hour test period. This development will help speed the 

adoption of herbicide-reducing intermittent spray systems on large-acreage farms. 

A Wireless Sensor-based Site-specific Irrigation Solution. To save water resources 

and minimize agrichemical leaching to groundwater, a sensor-based site-specific 

irrigation approach was developed by the Northern Plains Agricultural Research 

Laboratory at Sidney, Montana This approach incorporates an in-field wireless sensor 

network and variable-rate irrigation control for on-farm use. Sprinkler nozzles can now 

be controlled wirelessly by a real-time information feedback of the soil-water status of 

the crop. This technology allows growers remote access to field conditions, and real-time 

control of site-specific irrigation technology can help ensure that the correct amount of 

water is applied at the right time, thus reducing the risk of crop loss and inefficient water 

use with associated energy usage. 

 New Sensor Offers Accurate Way to Estimate Crop Residue Cover for 

Conservation Management Compliance. Accurate and rapid methods for determining 

tillage and crop residue cover are limited at the field and watershed scale but are needed 

for assessing Conservation Program qualification and compliance. Scientists at the 

Southeast Watershed Research Unit, Tifton, Georgia and J. Phil Campbell, Sr., Natural 

Resource Conservation Center, Watkinsville, Georgia, found that a handheld 

multispectral radiometer sensor could be used to detect tillage and residue cover 

differences on Coastal Plain and Piedmont region soils as well as currently used time 

consuming line-transect estimates. Residue cover indices that were developed to 

differentiate between conservation and conventional tillage could be valuable tools for 

USDA-NRCS and other agencies to make rapid watershed-scale assessments of 

conservation tillage adoption. 

Spatial Analysis-of-Covariance Method Uses Farmer Precision Agriculture 

Information. USDA-ARS scientists at the Genetics and Precision Agriculture Research 

Unit in Mississippi State, Mississippi have developed an improved way to analyze whole 

field experiments using real-time on-farm data that are collected by farmers. Three data 

set applications of the methodology were utilized: (1) the effect of herbicide drift on corn 

growth and yield as related to the topography co-variates of imagery and elevation; (2) 

the response of nematode treatment strategies as related to topography co-variates of 

imagery and VERIS soil conductivity data; and (3) the use of ARS methodology used by 

a cooperator in Louisiana to determine the effects of variable-rate nitrogen applications in 

tandem with variable-rate nematode control. In all three applications, the custom ERDAS 

Imagine application built cooperatively with Leica was tested and extensively used in 

these spatial co-variate analyses for the first time. This custom application is able to 

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generate polygons of different widths and lengths according to polylines of travel 

followed by commercial application equipment. This ERDAS Imagine application was 

also provided for individual use by cooperators at Mississippi State, Stoneville 

Experiment Station, and the Louisiana State University Experiment Station at St. Joseph, 

Louisiana. 

Tolerances Determined for Optimal Benefits from Automatic Steering to Control 

Equipment Traffic. Producers in the southeastern Coastal Plains region use strip tillage 

prior to planting in order to manage soil compaction in conservation tillage systems. 

USDA-ARS scientists from the National Soil Dynamics Laboratory in Auburn, Alabama 

determined how automated steering controls could be used to improve the accuracy of 

deep tillage and planting operations in high-residue conservation tillage systems. Results 

showed that if deep tillage was two inches away from the planting row, cotton yields 

were reduced by 24-52% with net revenues reduced 38-83%. Because of the costs of the 

technology, larger farms are most likely to benefit from highly accurate automatic 

steering systems, while smaller farms may need to use cheaper alternatives, such as foam 

markers placed over strip-tilled rows. 

Strip Tillage Technology Developed for Sugarbeets. Three years of research by 

USDA-ARS scientists at the Northern Plains Agricultural Research Laboratory in Sidney, 

Montana have shown that strip tillage on sprinkler-irrigated sugarbeets leads to 

substantial fuel savings by greatly reducing the number of tractor passes required to 

establish the crops, compared to conventional tillage practices. Also as a result of striptillage, the percentage sucrose in the beets was consistently higher with equivalent yields 

as conventional tillage. This work is has been well received by growers in the MonDak 

region of the Northern Great Plains, who have adopted the practice on 5000 acres in 2007 

(up more than 400% from 2006). 

Precision Nitrogen Applications Could Reduce Nitrogen Fertilizer Use in the Pacific 

Northwest. Current wheat management strategies in the Pacific Northwest largely ignore 

spatial and temporal interactions between the crop and environment. USDA-ARS 

scientists in the Land Management and Water Conservation Research Unit at Pullman, 

Washington tested the effectiveness of geographical information system referenced 

information to assess the efficacy of precision nitrogen management on wheat 

performance and economic returns. Precision applications reduced nitrogen (N) fertilizer 

use by up to 20% compared to uniform N management, without negatively impacting 

grain yield or protein content. In addition to reducing the costs of nitrogen fertilizers, the 

undesirable consequences of agricultural chemical movement from the field could be 

reduced. 

Improved Wheat Yields and Quality Achieved with Variable Application Rate 

Technology. As input costs increase, producers throughout the U.S. are seeking ways to 

maintain crop yield and quality while decreasing production cost. The Integrated 

Cropping Systems Research Unit in Brookings, South Dakota utilized variable-rate 

technology that is currently in use in the southern Great Plains to apply variable rates of 

nitrogen fertilizer based upon in-season winter wheat plant nitrogen needs. The average 

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amount of nitrogen needed to obtain maximum yield and quality decreased significantly 

over traditional soil test nitrogen recommendations, potentially reducing the impact of 

nitrogen fertilizer losses from fields to water sources, and decreasing overall production 

costs in the Northern Great Plains region. 

Wheat Nitrogen Status Index Developed Based on Remotely Sensed Information.

Exhaustive field sampling needed to acquire broad-scale information on in-season crop 

nitrogen status is constrained by high cost and lack of time. USDA-ARS scientists at the 

Columbia Plateau Conservation Research Center in Pendleton, Oregon investigated how 

remote sensing could be used to rapidly map crop nitrogen deficiencies across entire 

wheat fields in the Inland Pacific Northwest region. Ground reference measurements of 

crop canopy reflectance were converted to the band equivalent reflectance of the 

RapidEyeTM satellite series. Using this information, a new vegetation index was 

developed from the red-edge band that is highly correlated with leaf chlorophyll and 

nitrogen contents. This new approach overcame the limitations of conventional indices, 

which are confounded by crop growth variation caused by differences in plant available 

soil water. The novel index enables prediction of nitrogen status across wheat fields and 

can be used to make decisions about fertilizer nitrogen management at mid-season 

without having to rely upon costly ground sampling methods. Combining this new 

technology with variable application rate methods will help make precision application of 

fertilizer nitrogen a reality. 

Sensors on Combines Used to Provide Real-Time Estimates of Grain Quality. The 

advent of near infrared (NIR) on-combine sensors gives growers the opportunity to 

measure and map the grain protein concentration of wheat during harvest across farm 

fields. Scientists at the Columbia Plateau Conservation Research Center in Pendleton, 

Oregon used an in-line NIR sensor on a grain harvest combine to measure the protein 

concentration of soft white wheat within 0.5% accuracy. This finding supports the use of 

on-combine sensing during harvesting to segregate grain based on protein concentration, 

thus enabling growers to better capture price premiums in value-added markets that pay 

premiums for quality. 

CERES-Maize Model Estimates Best Strategies for Corn Produced under Limited 

Water Conditions. USDA-ARS scientists at Agricultural Systems Research Unit in Fort 

Collins, Colorado validated the CERES-maize model for dryland and irrigated corn 

production conditions at Akron, Colorado and evaluated production responses to different 

levels of limited irrigation over 92 years of historical weather records. The study found 

that 20% of limited water application during vegetative stage and 80% during 

reproductive stage of corn was the best recipe to save water with no effect on yield. This 

study provides evidence that a system model can help develop location-specific 

agronomic practices to maximize water use efficiency under limited water conditions. 

Concepts developed in the study will be adapted to other locations, climates, and crops. 

Corn and Soybean Field-scale Responses to Soil Water Availability Interpreted.

USDA-ARS scientists at the National Soil Tilth Laboratory in Ames, Iowa used many 

years of observations across many corn and soybean fields in central Iowa to reveal 

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seasonal patterns of soil moisture variation that are related to the stress dynamics of crops 

through out the growing season. Reflectance patterns based on hyperspectral wavelengths 

from 0.4 to 1.2 μm were based on bare soil patterns within the field. In average rainfall 

years, the variation across the fields during April through June was minimal at the time of 

maximum vegetative development. Soil water was not a limitation to growth, except in 

years with excessive rainfall in low areas of fields that caused water-logging and crop 

death. When rainfall was below 60% of normal, water deficits occurred in low waterholding capacity soils. With these findings, it was determined that excess rather than 

limited rainfall was typical for central Iowa. Spatial variation increased during the grainfilling period because the evaporation rate of the crop increased and the rainfall amounts 

decreased, making the crop depend on stored soil water within the field. Spatial patterns 

of stress in early August are related to final yield maps collected at harvest. Comparison 

of various vegetative indices related to biomass, leaf area, or plant senescence rate all 

exhibited the same pattern during the growing season. Soil moisture spatial patterns 

within fields outweighed the patterns induced by nitrogen management or planting rates. 

Efforts to decrease variation within fields will have to focus on methods of increasing soil 

water availability to offset water stress late in the growing season. 

Satellite Imaging Used to Identify Crops in Field Across a Landscape. Landscape 

scale knowledge of crop production is necessary to understand how different production 

practices impact natural resource quality, but collecting such information from the ground 

is expensive and time consuming. USDA-ARS scientists in the Forage Seed and Cereal 

Research Unit in Corvallis, Oregon applied existing satellite image technology to identify 

crops produced for every field within a western Oregon watershed and the tillage 

practices used to establish these crops. Information derived from these images enabled 

participating scientists to establish water quality monitoring studies to quantify the effect 

of tillage practices on the amount of nitrogen in ground and surface waters. This novel 

application of satellite imagery to landscape land use analysis has provided a relatively 

inexpensive approach to correlate land use practices, including tillage of agricultural 

fields, with water quality and wildlife habitat. 

Electrochemical Sensing for Precision Management of Soil Macronutrients. Soil 

sample collection and analysis is costly and time-consuming when applied at the intensity 

needed for variable-rate fertilizer management systems. Scientists at the Cropping 

System and Water Management Research Unit in Columbia, Missouri have developed an 

efficient approach to sensing soil macronutrient status of crops as a machine moves 

across a field. Soil nitrate, phosphate, and potassium ion-selective electrode (ISE) sensors 

were used with Kelowna multiple-element extracting solution to accurately quantify 

nutrient levels in laboratory solutions. With proper calibration procedures, the ISE 

sensors can accurately measure nutrient levels in typical agricultural soils. The 

combination of sensors and the associated extracting solution could be incorporated into 

an overall nutrient sensing system that could be used to reduce fertilizer application 

through precision application management. 

New Decision Making Capacities Using the MAIZSIM Corn Simulation Model.

Integrated multiple-objective economic and environmental effects assessments are 

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needed at varying scales for agricultural systems across the United States. USDA-ARS 

scientists in the Crops Systems and Global Change Laboratory at Beltsville, Maryland 

have completed a new mechanistic corn simulation model named MAIZSIM. Previously, 

there were no comprehensive mechanistic corn models that simulated the plant processes 

using biologically based light interception, photosynthesis processes, and carbon 

partitioning. MAIZSIM will be an important management and assessment tool for 

agricultural managers, scientists, and policy makers who desire to consider different 

strategies to increase corn production under existing or changing climate conditions. 

Improved Accuracy Built into the SPUDSIM Potato Simulation Model. USDA-ARS 

scientists in the Crops Systems and Global Change Laboratory at Beltsville, Maryland 

have improved the accuracy of the SPUDSIM potato model to simulate canopy light 

absorption and photosynthesis. State-of-the-art advances in our knowledge of light 

attenuation and gas exchange processes within the crop canopy are not incorporated in a 

majority of existing potato models. The accuracy of SPUDSIM predictions has been 

improved by incorporating process-level information on leaf gas exchange response to 

the light environment. Mathematical expressions for leaf appearance, duration, and 

expansion were also incorporated into SPUDSIM. The modifications were validated with 

independent data. These additions improve the usefulness of the model for policy 

decision makers and growers to evaluate the effects of management decisions on potato 

production. 

Model Approach Evaluating the Effectiveness of Cover Crops Used to Reduce 

Nitrate Leaching in Tile Drainage Systems. Including winter cover crops such as 

winter rye in corn-soybean rotations is one of the more promising practices to reduce 

nitrate loss from tile drainage systems without negatively affecting production. USDAARS scientists at the Agricultural Systems Research Unit in Fort Collins, Colorado have 

tested the RZWQM-DSSAT hybrid model for simulating the effects of cover crop versus 

no cover crop on nitrate leaching losses in subsurface drainage water. Field experimental 

data collected over several years from Boone County, Iowa were used to calibrate the 

model. Average observed and RZWQM-simulated flow-weighted annual nitrate 

concentrations (FWANC) in subsurface drainage water for the cover crop treatments 

were reduced 61% and 50%, respectively, for actual measured and model-simulated 

waters from tile drainages. This modeling approach can help farmers and conservation 

planners determine the best places to use cover crops to achieve desired reductions in 

nitrate losses from fields. 

Autocalibrated Version of the Soil Water Assessment Tool (SWAT) Model Applied 

to National Weather Service Flood Predictions. New technology has improved the 

kinds of weather data available to be used to increase the precision of flood predictions in 

the United States. However, appropriate models need to be identified that can utilize 

those data and accurately predict flood conditions. USDA-ARS researchers at the Forage 

Seed and Cereal Research Unit in Corvallis, Oregon have developed an automated 

method to calibrate the SWAT mode which was developed by the scientists at the 

Grassland Soil and Water Research Laboratory in Temple, Texas. The robustness of the 

autocalibration routine was demonstrated in a nationwide competition sponsored by the 

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National Weather Service where the USDA-ARS team was able to rapidly estimate the 

hydrology of five test watersheds using hourly radar data. The USDA-ARS team results 

compared very well with observed data, validated the use of SWAT, and provided a 

calibrated model that can be used as a flood prediction guide for the National Weather 

Service. 

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