Comparison of Organic Farming Systems Using Off-Farm Nitrogen with - without Animals

Final Report for LNE02-158

Project Type: Research and Education
Funds awarded in 2002: $149,968.00
Projected End Date: 12/31/2006
Matching Non-Federal Funds: $200,626.00
Region: Northeast
State: West Virginia
Project Leader:
Sven Verlinden
West Virginia University
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Project Information


The objectives of this project were to evaluate the sustainability of organic farming systems that rely on biologically-fixed nitrogen versus those using off-farm nitrogen to maintain cropland, and to compare the production, soil quality, and environmental impacts of crops-only organic farming systems with systems integrating crops and livestock. The project continued one begun in 1999 when the West Virginia University Horticulture Farm underwent the transition to organic practices. Replicated field trials in vegetable (market garden) and field crops using a randomized factorial design continued through 2005 after a three year transition phase. Plots receiving compost were amended with compost to supply 150 pounds nitrogen per acre each year to enhance soil fertility. A four-year crop rotation was maintained in both market garden and field crop farming systems. In addition, in the field crop system, livestock production (sheep and poultry) and pasture was integrated into half of the field crop systems. Pest management practices were evaluated in replicated field plots and in on-farm trials with five grower-cooperators. The results have lead us to the following major conclusions. First, high input systems yield consistently higher than low input systems in both the market garden and field crops. Yield difference range from 10-30%. The only exception are peas which consistently yield higher in low input plots. A decision to apply compost will therefore have to be based on the individual crop yield differentials, cost of the compost, and the price of the final product. All of these factors have been incorporated into a compost rate application model or decision tree for growers. Second, organic matter (OM) content is lower in low input plots when compared to high input plots. However, OM has increased over the last 4 years in both the low and high input plots at similar ratesin both field crop and market garden plots. Third, organic sheep production by means of rotational grazing can build and maintain a productive and healthy flock. Fourth, chickens can be economically and organically reared without synthetic methionine, a supplement seen as essential in conventional broiler chicken production. Fifth, yields of most crop respond to compost application in a dose-dependent manner. Salt and nutrient build up in soils with high rates of compost application in addition to the dose-dependent response of crops indicates that compost should be applied in a judicious manner based on soil analysis and the plant nutritional needs. Sixth, succesful organic pest management of Mexican Bean Beetle, Stripped and Spotted Cucumber Beetle, Fusarium and Pythium seed and root rots has been accomplished and dessiminated to local growers. Seventh, results have been communicated to extension personel, growers/farmers, graduate students, and undergraduate students through hands on work experience, an organic production course, extension fact sheets, on-farm demonstrations, field days, WVU organic farm visits by growers/farmers, and personal contact between the investigators and grower/farmers throughout the project. We have met or exceeded expectations in four of our original five performance targets while falling short in only one the performance targets we set out to reach.


Research to evaluate farming systems for transition from conventional to organic farming was initiated at the West Virginia University Organic Farm in 1999. Rotation studies begun in 1999 in both vegetable and field crops were continued for an additional 4 years from 2002 through 2006 in order to complete the originally planned 4-or 7 year crop rotation sequences. The replicated factorial experiment started in 1999 and continued under the current project evaluated the effects of, and interactions with, compost amendment and livestock from the initial transition phase through the establishment of organic production. The WVU Organic Farm project was uniquely situated in that it was one of the few organic farming studies where replicated designs could be carried out within the context of an entire experimental farm operated under organic practices beyond the transitional phase of conventional to organic production. In this project the continuation and completion of rotation sequences should help us establish and predict long term trends in yields and changes in soil quality. In addition, the integration of free-range poultry as a component of the livestock systems, and increased efforts in soil microbiology and nutrient cycling studies has lead to a better understanding of nutrient retention and losses in organic farming systems while also establishing protocols for organic free-range poultry production.

Performance Target:

Performance Targets

1. Ten growers identified from our grower advisory committee, attendees at Farm Field Days, or commodity organizations will base, at least in part, their compost use rates on soil quality and economic performance criteria devloped from this phase of the project.

2. The proportion of growers that are transitioning from conventional to organic production that have incorporated research and cost-benefit results in their decision-making in designing a transition system for their operation will increase to 50%.

3. Nine undergraduate students will be trained in organic farm practices through internships. Farm-related experience will be provided to additional undergraduate and graduate students through work experience, research opportunities, field days, and classroom and non-classroom activities.

4. Five growers per year, identified at field days and through direct contacts, will participate in on-farm evaluations/demonstrations of selected practices in the following year. These selected practices will include: use of barriers (row cover, particle film sprays, etc.) for pest management; rotation practices, diversification through integration of livestock into the farming system, and weed management using mulches.

5. Twelve producers will incorporate practices for management of internal parasites in sheep using either rotational grazing and/or alternating sheep and poultry on pastures.

Specific Research Objectives

1. Compare the sustainability of a farming system relying on biologically fixed nitrogen with one using approximately 150lb/acre/year of off farm nitrogen to maintain cropland.
2. Predict long term effects of source and amount of N on the sustainability of organic systems.
3. Compare production, soil quality, and environmantal impacts of crops-only organic farming with systems integrating crops and livestock.


Materials and methods:

Farming Systems Research:

Two replicated farming systems experiments, field crop/livestock and vegetable market garden, were continued from a previous project for this study. Each compared two treatments for managing soil quality: a low input treatment using legume-based crop rotations only, and high input treatment using legume-based crop rotations with off-farm compost amendments. At the start of this project (2002), plots had completed 3 years of a 4 and 7 year crop rotation in both experiments. The low input systems used biologically-fixed nitrogen only (legumes in rotation and winter cover crops). In this project low input plots were planted to rye-vetch winter cover crops. The rotation in thr market garden consisted of four replicate plots, each planted with legumes (peas and beans), solanaceae crops (tomato and peppers), cucurbits (pumpkins and zucchini), and leafy crops (spinach and lettuce). In the field crop experiment, three replicate plots each of potato, soybean, wheat, and a brassica were grown in a continuous rotation in the without-livestock system. In the with-livestock system, the 4 year rotation was followed by 3 years of an orchard/red clover pasture (three replicates)grazed by sheep or used for hay production.
In the high input systems in both experiments the plots are supplemented with 10 tons/acre of aff-farm dairy manure compost. All rotation and other management practices are idential for both low and high input plots. Free-range poultry was added to the with-livestock systems in order to evaluate the feasibility and economics of organic poultry production. Changes in the rate of nutrient cycling by livestock was evaluated for a correlation with overall system productivity to determine whether livestock increases productivity without increasing the total amount of nutrients added to these systems.

Monitoring Program:

Detailed records were kept of all operations in each experiment so that enterprise budgets could be produced. Inputs of materials, labor, and equipment use and quantity and quality of harvest were recorded. Weather data continued to be collected and summarized to correlate physical and biological parameters with year to year climate variability. Pasture and cropped soils were sampled at 0-3 inches, 3-6 inches, and 6-12 inches. Chemical properties monitored include organic matter, pH, and nutrient ions.

Component Research:

Compost Rate Applications
A randomized design with six application rates of composted cow manure (including a control), and three replicates per rate was continued on small plots. Measurements of these plots included regular soil sampling and measurements of yields. Crops grown on these plots included pumpkins, sunflowers, buckwheat, green beans, Celosia and statice cut flowers.

Weed Management Alternatives
A randomized complete block design with four replications compared six weed management treatments. The treatments were an unweeded control, hand cultivation, poultry litter at 1.5 and 3 tons/acre, black plasic mulch, and reflective silver plastic mulch. Because of their sensitivity to weed competition, peppers served as crop in this experiment. Yield, treatment costs, and weed biomass and community composition was assessed.

In addition to specific research in the original proposal the project provided infrastructure for additional research in organic practices. For example, effective control methods to minimize the effect of Mexican Bean Beetle attack on green beans were tested. Methods tested included the release of a parasitic wasp, row covers, and staggered plantings. Other research included a potato and other crop variety trials, companion planting experiments, seed and root rot management and weeder geese weed management experiments.

Research results and discussion:


1. Obtain organic certification for the WVU Organic Research Farm in 2003

The WVU Organic Research Farm was certified by OEFFA as a bona fide organic farm in 2003. The whole farm has been certified organic every year since including the final year of this project (2006).

Growers are skeptical of research conducted on conventional farms and question the relevance of results from studies on non-certified land. Certification has had a twofold impact. First, researchers working on this project have developed a better understanding of grower concerns and questions surrounding certification and the investigators have been able to develop research in formats most usable by growers (component research). An example is the succesful introduction of a parasitic wasp for Mexican Bean Beetle control in green beans resulting in 30% higher green bean yields compared to a control. A control method now used by 3-5 growers in the WVU/Morgantown area alone.

2. Develop educational materials to advise growers seeking to transition from conventional to certified organic practices in vegetable, field crop, and livestock production.

We have developed 7 extension fact sheets related to transitioning and managing organic production systems. These factsheets can be accessed at In addition information is now available by contacting the Division of Plant and Soil Sciences on rotational grazing of sheep (Dr. William Bryan), choosing appropriate compost application rates (Dr. Louis McDonald), Mexican Bean Beetle control (Dr. Sven Verlinden), companion planting (Dr. James Kotcon), and weed management in peppers (Dr. Rakesh Chandran). More information is also available through the Division of Animal and Veterinary Sciences on organic poultry production(Dr.Joseph Moritz). Dr. Moritz work, results and conclusions included, has been widely desseminated in trade magazines because he is one of very few researchers working on organic poultry production. Additional factsheets and a experiment staion bulletin based on the aforementioned researcher’s and WVU organic farm results are also being developed.

3. Develop Extension Recommendations for model organic production systems to assist existing organic producers achieve more stable production and profitability.

See Milestone 2

4. Complete the evaluation of the 4 and 7 year rotations and the impact of systems on soil quality. Submit the results for publication in peer-reviewed journals.

We have processed and analyzed all data collected for growing season 2003-2005 and will be submitting the results and discussion of our findings to refereed journals in 2007. Specific results and discussion, including graphs/tables, is available from NE-SARE as a separate document.

Two publications were submitted for publication based on data obtained during the project years 2003-2005. One of those has been published, the other is currently being reviewed.

J. S. Moritz, A. S. Parsons, N. P. Buchanan, N. J. Baker, J. Jaczynski,O. J. Gekara, and W. B. Bryan. 2005. Synthetic Methionine and Feed
Restriction Effects on Performanceand Meat Quality of Organically Reared Broiler Chickens JAPR: 521-535

Verlinden, S., McDonald, L. 2007. Organic and Inorganic Mineral Nutrition of Statice (Limonium sinuatum cv. Soiree Mix) and Cockscomb (Celosia argentea cv. Chief Mix). Scientia Horticulturae X:XX (in review)

5. Document expanded participation at the annual field days and use of updates to growers.

Participation in field days has declined but stabilized in the last 3 years of the project from 150-200 to 60-75 people. However, the percentage of growers/farmers increased significantly from approximately 10% to 50%. This was the result of the addition of a number of grower-targeted workshops to the field day and a decline in general population (backyard gardeners) partcicipation.
Participation in on farm trials has been mixed and ranged from 3 to 5 growers per year throughout the project.

6. Assist student interns in developing long-term careers in organic production by providing experience and training needed to begin their own organic businesses.

We have trained a total of 13 interns and 4 graduate students during the 4 year period of this project. Interns and graduate students have had minimal success in starting their own organic business. However, at least one intern found employment as an organic certifying agent in Maine and many of the interns have used their internship to bring sustainable practices to the position in agriculture they currently hold.

7. Demonstrate successful organic livestock production by increasing the size of the sheep flocks through production of healthy lambs and by using sheep and poultry to add value to farm products not currently being fully utilized.

We succesfully increased our sheep flock from 60 to 200 sheep/lambs with limited problems controlling internal parasites. In addition, several hundred chickens were reared with organic feed on several occassions. One hundred wool blankets have been produced and sold for $150 demonstrating signficant added value with diversification of organic farms into finished products. Both chickens and sheep have been used to graze pasture and crop residue adding value to otherwise limited value farm resources.

Participation Summary


Educational approach:

Peer-reviewed articles

Mortiz, et al. 2005. Synthetic Methionine and Feed Restriction Effects on Performance and Meat Quality of Organically Reared Brioler Chickens. JAPR: 521-535

Verlinden, S., McDonald, L. 200X. Inorganic and Organic Nutrition of Celosia and statice. Scientia Hort.(submitted)

Scientific papers reporting results from the project were presented at meetings of the Weed Science Society of America, the American Phytopathological Society, the Agronomy Society of America (NE branch), and the American Society for Horticultural Science.

Fact sheets
See Results and Discussion/Outcomes Section

one Ph.D. thesis
seven M.S. thesis
Annual field days were organized with attendance ranging from 70 to over 200 interested parties including approximately 25-30 professional growers/farmers. Field days included presentations and tours to highlight ongoing research and results, workshops, and displays.
Visits by a group of 40 goat/sheep producers from Kentucky lead by Kenneth Andries, Animal Science Specialist, Kentucky State University, WVU extension agents and clientele groups, NRCS personel, and the WVDA.

Additional Project Outcomes

Project outcomes:

Impacts of Results/Outcomes

Impact of results

Participation of Dr. Moritz in this SARE grant resulted in a very important manuscript that has received much attention. He has been interviewed by a number of trade journals regarding the paper. In addition, this paper has made a major contribution to the achievment of WVU receiving a USDA-NRI grant for further organic poultry research.


We know have stable core of active grower-cooperators who turn to the WVU for information on organic production, attend the field day, contact us about summer internships and in some instances are employing our students. Our credibility with this group is very high, because of organic certification status of the farm, our whole farm research strategy, and admitted research failures.

Students (undergraduate and graduate)
The WVU organic farm has been instrumental in providing hands on experience and teaching opportunities to many undergraduate and graduate throughout this project. It has allowed us to offer a new major in agroecology and an undergraduate and graduate level course in organic crop production.


Performance Target 1 Outcome: At least 12 growers/farmers are using WVU organic farm research results and recommendations on compost application as of the 2006 growing season. We can confidently say that we exceeded this perfomance target.

Performance Target 2 Outcome: We were not able to incorporate growers/farmers who were transitioning into our pool of grower-cooperators and therefore could not reach a satisfactory outcome for performance target 2.

Performance Target 3 Outcome: We trained and supported the work of 13 undergraduate (internships or hourly work experience) and 10 graduate students during this 4 year project. In addition the farm was used for field trips and as support of the organic production course now routinely taught at WVU. We can therefore confidently say that we exceeded the expectations of performance target 3.

Performance Target 4 Outcome: Five growers per year, with a large turn over ratio from year to year, participated in our on farm trials, evaluations, and/or demonstrations. The most important concepts or techniques tested were rowcovers, particle films, and parasitic wasps as an insect management strategy and vinegar and/or mulching as a weed management strategy. Performance target 4 and its outcome were therefore met at original performance target level.

Performance Target 5 Outcome: Dr. Bryan was instrumental in reaching, most likely exceeding performance target 5. Informal contacts throughout the 4 year project, in addition to formal contacts (a group of 40 goat/sheep producers visited the farm in 2006 and the average attendance of 5-10 farmers at the annual rotational grazing workshops at the WVU organic farm field day)lead us to think that at least 15 farmers are now using rotational grazing in one form or another. The animal science specialist from Kentucky State University who made the farm a stop on a field trip for 40 Kentucky farmers (see above) indicated in a thank you letter that 1/4 to 1/3 of the group will have tried some type of rotational grazing for sheep or goats in 2006. We can therefore say, with some confidence, that performance target 5 was met and possibly exceeded the expectations of the original grant proposal.

Economic Analysis

An economic analysis has not been performed.

Farmer Adoption

Farmer adoption has been mixed as some techniques and/or management strategies proved to be less than adequate when put into practice either at the WVU organic farm or at grower- cooperator farms. The most successful adoption has been seen in insect control (rowcover and parasitic wasp release), compost use, and rotational grazing. We now provide Pediobius wasps to three growers every growing season to control Mexican Bean Beetles in green beans(obtained in bulk from New Jersey Department of Agriculture and distributed by the WVU organic Farm). Most growers (5-7) producing zucchini now use row covers until first bloom to protect their crops from striped and spotted cucumber beetle). Although farmers still use compost as available, when available all of the farmers in contact with the WVU organic farm project use compost judiciously based on the recommendation not to exceed 20 tons/acre of composted dairy manure-leaf litter type compost. We have effectively stopped ‘a little bit is good, more is better’ attitude that was present early on in the project about compost applications. Rotational grazing as perscribed by the WVU organic farm project is very labor and material (fencing) intensive and is only used by one farmer. However, varietion on our rotational grazing protocols and its use for other animals(goats) is common place in the group of farmers that produce livestock and interacted with the WVU organic farm project during the last 4 years.
Major disappointments in farmer adoption have been seen in particle film and row cover use/applications for crops other than zucchini, vinegar sprays as a weed control alternative, and the use of specific compost rate applications for specifc crops other than the above described general and modest adoption of our recommendations.

Assessment of Project Approach and Areas of Further Study:

Areas needing additional study

Farming Systems
In order for us to determine long-term sustainability of the farming systems under study, crop rotations should continue for the forseeable future. Variability in climate, herbivory by deer, ground hogs, and rabbits, insect and disease pressure have made the establishment of trends in yields difficult to analyze. Soil quality data are less prone to the above described variability and patterns are therefore more easily established (see results and discussion).

Organic Management Practices
Weed, disease, and insect management remain high on the list of grower questions and input on what type of research to conduct. There is a clear need to continue component type of research to find suitable organic management practices for a number of weeds, diseases, and insects. Diseases of particular interest to the WVU organic farm and growers for future research include root rot complexes in cool season crops, powdery mildew in cucurbits, and late blight in tomatoes. Although we have found a number of control methods for insect pests such as Mexican Bean Beetle, striped and spotted cucumber beetle, a number of insect problems remain, including flea beetle infestations, squash vine borer, and japanese beetles.

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.