Planting for Resilience

Reflections on Cover Crops and the Vital Role They Play in Organic Farming

By April Thatcher, farmer at April Joy Farm and OFRF Board President

cover crop seeds including oats, radish, vetch, barley, and red clover.

Cover Crop Seed at AJF | Oats, radish, vetch, barley, and red clover.

Cover crops are a central part of balance on my Southwest Washington farm. In fact, they’re a vital tool in organic systems across the United States, helping to regenerate the soil, suppress weeds, and build resilience in the face of a changing climate. And yet, I’ll admit, for all their benefits, cover crops have been a source of some head-scratching moments for me over the years.

When I first started using cover crops, I had a lot of questions—many of the same ones I still hear from other new growers today.

What mix of plants will work best with my soil type, climate, and crop needs?
How do I know my cover crops are adding value to my system?
What type of equipment do I need to manage cover crops successfully?
And perhaps the most common question I get from fellow farmers is: How do I transition from a lush, green cover crop to a seedbed ready for planting without disturbing the soil too much?

Organic farming is a relationship between the land and the farmer, and I think of cover cropping as one big, ongoing conversation in this relationship. It’s a journey of experimentation, observation, learning, and refining techniques year after year. Each piece of land, each crop, and each season calls for a different approach, and what works for one farmer might not work for another.

On my farm, I’ve spent years experimenting with different cover crop mixes and timing strategies. I currently use a mix of cover crops—grasses, legumes, and broadleafs—depending on what I observe the soil needs. Legumes like peas and clover can add nitrogen to the soil, while deep-rooted crops like daikon radishes help break up compacted layers and improve soil structure. The key for me is to support functional diversity—both above and below the ground.

The Role of Cover Crops in a Living Soil System

When we treat soil as simply a medium to grow crops, we miss out on the extraordinary potential it has to regenerate life, sequester carbon, improve the nutritional value of our food, reduce off farm inputs, and to act as a buffer against the many challenges we face today.

Cover crops are a powerful tool to help unlock this potential. These crops are not meant to be harvested but rather are grown specifically to feed the soil. When used strategically, cover crops can help reduce soil erosion, capture and recycle nutrients, promote nitrogen fixation, increase organic matter, suppress weeds, and even manage pests—all while nurturing the living, complex web of life in our soils.

Cover crops are a critical tool in the organic farmer’s tool box to help build resilience on the ground—not just in the soil but in our entire farm ecosystem. And that resilience is more important now than ever as climate change presents erratic new challenges to farmers across the country.

Lessons from the Field: Cover Cropping in Practice

A green tree frog perched on the leaf of a kale plant in an organic farm field.

Cover Crop Kale | Sometimes, we don’t mow or turn under our market crops after we’ve finished harvesting. We underseed cover crops directly into these fields because, like cover crops, these plants continue to provide benefits for our system. Case in point- this tree frog has it made in the shade. Photo credit: Lauren Ruhe

I’ve learned over the years that there is no one “right” way to utilize cover crops. I’ve surrendered to the reality that on highly diversified operations like mine, cover cropping is always going to be a process of experimentation, observation, and refinement. What works one year might not work exactly the same the next, and that’s okay. If we are observant and committed to keeping records of our trials, we can glean important knowledge every season of the year. The goal isn’t perfection; it’s progress.

After eighteen years of working with cover crops on my 24 acre farm, here’s a bit of what I have gleaned – what I would tell my new-farmer-self if I could:

Start simple and make small adjustments to your basic cover crop plan year over year. When I first started utilizing cover crops I was overly enthusiastic. Every year I’d try a bunch of different, complex seed mixes to try and find the perfect one. That was a mistake. I wish I’d stuck with a simple mix of two or three species (grass/legume/broadleaf) for the first few years. If I had done so, and made small refinements year over year, (adjust seeding rates, sowing dates, etc.) it would have saved me time in the long run. Instead of changing way too many variables every year, I would have built up a steady, reliable mix customized to my system faster- one that incrementally added stacking benefits to my system year over year.
Pick only one (or two at most) goals. I had so many needs when I started using cover crops. I had soil compaction, low nitrogen, low organic matter levels, and erosion and leaching to worry about. But starting out, I would have been better off picking just one of these to focus on addressing through the use of cover crops instead of trying to solve all of them at once. Over time, you can build on your success. But aim for the small wins, having faith they will add up over time.
Be mindful of your equipment and resource limits. We have hot, dry summers at my farm. So interestingly, irrigation is a big challenge for me in terms of using summer cover crop crops. Same goes for sowing fall cover crops, which I want to sow as early as I can to maximize nitrogen fixation. Even though I have the equipment to sow, cultipack and terminate them successfully, if I can’t get them to germinate without water I’m at square one. If you don’t have equipment to crimp/roll cover crops or don’t have a flail mower, make sure to be strategic about the species in your mix. Have a plan for seeding, and have a plan for terminating your cover crops that is practical for your operation.
Nest your cover crops into your overall crop system. Your cover cropping plan has to work within the larger context of your farm plan. Part of this means being realistic about the resources (including labor) necessary to implement your cover crop strategy (see bullet point above). Part of this means being diligent about planning your cover cropping efforts as diligently as you do crops for your market. It’s all too easy in the heat of the season to bail on your cover cropping plan because some of the details aren’t quite worked out or you didn’t order seed, etc. Be intentional about making sure your cover crop system compliments versus competes with your market crop system. At my farm, tasks for cover crop soil prep, sowing, management, monitoring, and termination tasks are all included in my annual farm plan schedule. I don’t have to think about organizing or planning anything cover crop related once the season gets started; I can focus simply on implementation.

Every farmer who wishes to utilize cover crops successfully has specific soil health needs, goals unique to their operation, and different equipment and time constraints. So while there’s no single, universally right approach to cover cropping, we can all benefit from taking a strategic approach to working with cover crops.

Picture of summer cover crop in bloom. Includes Oats, White flowering buckwheat, orange California poppies, and purple phacelia.

Summer Cover Crop Mix | A favorite combination for warm weather. Oats, Buckwheat, Poppies and Phacelia.

Bridging Experience with Research: OFRF’s New Guide to Cover Cropping

That’s why I’m so excited to share a valuable new resource for farmers: a comprehensive organic cover cropping guide developed through OFRF’s ongoing partnership with the Natural Resources Conservation Service (NRCS). This guide is designed to help farmers—whether they’re just starting out with cover crops or refining their strategies.

What makes this guide so valuable is that it’s grounded in both science and experience. It combines years of research on the benefits of cover cropping with practical, field-tested strategies from organic farmers like myself. It provides an overview of the steps for selecting cover crops, managing them through the growing season, and terminating them in a way that benefits both the soil and the farmer’s bottom line. And it offers a collection of other regionally specific resources for farmers to dive in deeper. You can also find more in depth information in OFRF’s Soil Health and Organic Farming guide to Cover Crop Selection and Management.

Whether you’re looking to improve your soil’s health, reduce off-farm inputs, support pollinators, or make your farm more resilient to climate change, cover crops can be a powerful tool in your toolkit. This guide is full of practical, research-based advice to help farmers make informed decisions about how to integrate cover crops into their systems.

Get OFRF’s Cover Cropping Guide!

By admin|2024-10-21T15:59:49+00:00October 21st, 2024|Farmer Stories, News|

A Call for Action on Congressional Investments in Organic Research

farm field with first frost of winter

Earlier this morning we had our first frost of the year here on the farm in Vermont; late for our area yet it came all the same. The arrival of frost, whether early or late, is inevitable for the Northern regions of the country, a seasonal deadline that irrevocably holds firm. The same can’t be said for the Farm Bill or the federal appropriations process, behind their deadlines by 25 months and two months, respectively. But, both of these pieces of policy face a real deadline come December. Just as frost signals the arrival of a new phase in the agricultural year, the pending deadlines for these federal actions marks a pivotal moment for the future of agricultural research, climate resilience, and conservation programming.

Why the Farm Bill and Appropriations Processes Matter

Both the Farm Bill and the federal appropriations processes are the primary drivers of agricultural research policy, especially for those interested in organic production systems. At OFRF, our core concerns are:

Building resiliency to both climate and supply chain disruption through organic management and more localized food systems.
Investing in research for organic agriculture in order to provide answers to pressing environmental and production challenges.
Supporting the expansion of organic production to meet increasing market demand for organic products.
Making sure organic producers, and those interested in transitioning to organic production, have the research tools and opportunities needed to thrive.

Our existing Farm Bill and Appropriations Priorities still call for both legislative vehicles to authorize and then robustly fund organic agriculture research programs that our farmers so desperately need.

Unfortunately, progress on these crucial processes has been slow, and now Congress has just a couple short months left to meet the December deadlines. A delay beyond that will have real-world impacts—stalled funding could limit the USDA’s ability to support conservation programs, climate-smart practices, and organic research that underpins a resilient agricultural system.

Like our late first frost in the NE, increased federal investment in agricultural research is long awaited. Every dollar invested in research funding generates $20 in public benefits. Despite this high return on investment, funding for agricultural research has fallen by nearly a third over the past two decades. Today, organic produce makes up more that 15% of the total market, and yet less than 2% of USDA’s research budget is allocated to organic topics, and less than 1% of the Agricultural Research Service’s (ARS) budget is dedicated to organic research.

An Opportunity to Act During Congressional Recesses

As we’ve highlighted before, Congressional recess is a unique opportunity for you to engage directly with your elected officials, as many will be back in their home states and districts. It’s a great time to attend town halls, community events, listening sessions, or other scheduled appearances to hear from them and, most importantly, to have your voice be heard. Organizationally, OFRF is working to bring Members of Congress to organic research fields, joining with coalitions to express our appetite for a Farm Bill now, and bringing the stories of research projects to decision makers across the federal government this Congressional Recess.

Whether you’re a farmer, a researcher, or simply an eater, this is your chance to ask questions and emphasize the importance of strong federal support for organic agriculture research. Explain that organic agricultural research is not just for certified organic operations but benefits the entire agricultural sector by promoting climate resilience and sustainable practices. Check your local news sources for upcoming Town Halls and other events with your representatives.

Questions to ask your representatives:

How are they prioritizing funding for organic agricultural research in the upcoming Farm Bill and appropriations processes?
Will they commit to increasing investments in organic research to help meet national climate, conservation, and nutrition goals?
What specific steps are they taking to ensure that USDA programs support organic practices and long-term soil health?

Just as we all are noticing our signals of changing seasons in our home environments, these federal deadlines mark an important milestone for agricultural policy. December is fast approaching, and how Congress decides to act will shape the future of agricultural research for years to come. To continue the growth and success of organic agriculture and the businesses that rely on it, we need public investments that support the researchers who are answering crucial agricultural questions.

If you’re interested in getting involved or want to know more about advocating for organic research investments, please reach out to us. Let’s work together to secure a sustainable and resilient future for agriculture, one where organic practices receive the support they need to benefit all.

Eat well and breathe deeply,

Gordon

By admin|2024-10-10T17:48:55+00:00October 10th, 2024|Gordon's Policy Corner, News|

Farmer Led Trials Program Spotlight: A Different Chick Farm

Written by Mary Hathaway, OFRF’s Research & Education Program Manager

Tiffany Stanley, A Different Chick Farm

A Different Chick Farm is a Certified Organic family farm on just under 6 acres in Johnson City, Tennessee. Tiffany Stanley and her family began growing food for themselves as homesteaders, but saw demand from the local community. From this start in 2018, they expanded their operation into an abundant production featuring rare and heirloom fruits and vegetables, with a large focus on unique pepper varieties. Half of the farm is now a mixed orchard, planted with apples, peaches, nectarines, cherries, plums, pears, blackberries, raspberries and more. Rounding out the offerings at this diverse farm is a flock of heritage breed chickens that are pasture raised.

With the help of her son and husband, Tiffany grows over 300 types of peppers, mostly to create value-added products such as hot sauces, pickles, and jellies. The farm sells their pepper products and fresh produce at two local farmers markets, and a Community Supported Agriculture (CSA) program. Their homesteading spirit continues to grow, as they look to limit outside inputs into the farm and build a sustainable system with on-farm fertility management.

Producing On-Farm Compost to Reduce Inputs

A homesteader at heart, Tiffany wanted to explore how the farm could be more self-sustaining, especially in building their soil health with on-farm inputs. She was curious if the farm could make compost that could match the yields of commercial fertilizers. Building an on-farm compost regimen could help offset much of the fertilizer cost, and decrease the environmental footprint of the farm. There were a few factors that the farm considered: would the composting demand a lot more labor, would yields remain viable? As a family enterprise, there were risks in transitioning from a known and reliable yield from commercial fertilizers to a new and untested compost system.

Farm trial plan

With technical support from OFRF, Tiffany decided to get answers and compare two different on-farm compost recipes with her usual practice of applying Harmony, a granular fertilizer (5-4-3). Tiffany wanted to put her chickens to good use, so one compost recipe she wanted to try included chicken manure as the main nitrogen source for one of her compost formulas. Her second compost recipe in the trial used clover and fresh grass clippings as the main nitrogen source. Both recipes included wood chips as the primary carbon source.

One of her best fall cash crops is cucumbers, so the trial was designed for Socrates cucumber, transplanted out from her greenhouse to be planted in a 12×24 hoophouse in mid-September. At the time of transplanting, Tiffany would apply the different treatments: Compost recipe 1, Compost recipe 2, or the commercial fertilizer, respectively.

In farm trials, it is key to keep things consistent, so Tiffany made sure to count each plant that was transplanted so that each block had the same number of cucumber plants. Once the cucumbers begin to set fruit, she will weigh the yield as well as count the number of cucumbers from each plot. She is hopeful that the results of this trial will help her work towards building her on farm fertility plans, and keep harvests bountiful. Stay tuned for updates on the farm trial outcomes and findings this fall!

“I had a friend that was retired from NRCS tell me about the program and encouraged me to apply. I read many of the farm trials and what the program did to help organic farming and decided it was a wonderful opportunity. I am always looking for a better, more sustainable way to farm and was so excited to get picked for this program.”

– Tiffany Stanley, A Different Chick Farm

This story is part of a series profiling farmers who are taking part in OFRF’s Farmer Led Trials (FLT) program. Farmers receive technical support from OFRF to address their challenges through structured on-farm trials. To learn more about OFRF Farmer Led Trials Program, visit our website page at https://ofrf.org/research/farmer-led-research-trials/

To learn more about composting and farm fertility programs check out these resources:

To learn more about A Different Chick Farm, you can find them on Instagram and Facebook or visit their website: https://adifferentchickfarm.com/

Learn more about OFRF’s Farmer Led Trials Program

By admin|2024-10-10T13:09:52+00:00October 10th, 2024|Farmer Stories, FLT Highlight, News|

An Intern’s Journey into Food and Agricultural Policy with OFRF

By Julia Nelson

After spending a chunk of my first year of graduate school learning about food and agricultural policy in the U.S., I began my internship at OFRF with the goal of understanding how those policy mechanisms play out in the real world for the different parties involved in the process. Over the past 12 weeks, I have welcomed the opportunity to contribute to OFRF’s advocacy work focused on increasing funding for organic research in the most important U.S. agricultural policies – the agricultural appropriations and the Farm Bill. Through this experience, I have had the chance to practice a range of policy skills such as: writing catchy and persuasive email campaigns, synthesizing complicated federal data into a leave-behind document that tells a compelling story, and engaging in conversations with coalitions and members of Congress.

One major goal of this work is to spread awareness to Senators and Representatives on the various agricultural committees that funding organic agricultural research doesn’t just support the scientific community, but also contributes to the local economy and helps the country move closer to climate goals. Through this process, I have also been able to experience firsthand the nuts and bolts of the federal policymaking process and better understand how major political events (such as a looming presidential election) affect the pace of advocacy work.

Another hope of mine for this internship was to develop my professional skills in a way that would prepare me for future roles at nonprofit organizations or in public service. Because of its importance in the nonprofit world, I was interested in learning more about development and funding during my time at OFRF. I had the opportunity to help the Development team with prospect research, which meant I spent time researching and identifying foundations that were and were not a good fit for our needs. I enjoyed getting a sense of the funding landscape for organizations who work on organic agriculture and hope to continue working with grants in some capacity in my future career.

Additionally, I had the opportunity to put the data management and analysis skills that I have acquired through various statistics and economics classes to work. I helped with a few different data projects for the Policy team and the Research & Education (R&E) team, cleaning and categorizing large amounts of data on organic research from USDA and universities. The goal of my project for the Policy team was to be able to provide an honest estimate of the amount of federal funding that has gone towards organic agricultural research. The purpose of my work for R&E was to help populate OFRF’s soon-to-be organic research hub, which aggregates educational resources on organic agriculture to provide farmers with a one-stop shop of quality information. These projects reminded me of the importance of data in storytelling, illuminated the hard work that goes into any useful website that aggregates different resources, and reminded me that I need to keep up with my Excel skills.

Finally, on a different note, I appreciated being able to gain insight into how a remote, national organization operates and builds community. As I gear up for entering a workforce that is becoming increasingly virtual, it’s been helpful to see positive examples of how you can connect and develop relationships with coworkers without being face-to-face. I have really enjoyed the catch-ups that happen during staff meetings and our informal community-building Zoom calls.

Looking into the future, this experience has cemented my interest in pursuing the ‘policy’ part of my MS degree in Food and Nutrition Science & Policy after I graduate. My time with OFRF has reinforced my passion for working at the intersection of climate and food systems. As I begin the final year of my graduate program, I will be focusing my time on gaining the policy & organizational leadership skills I need to pursue a career at a government agency or nonprofit organization based in my home area of New England. I could not be more grateful to OFRF for providing me with an enriching internship experience, and also for the support and inclusivity of all of the team members I collaborated with throughout the summer.

By admin|2024-09-19T17:38:24+00:00September 19th, 2024|Gordon's Policy Corner, News|

Why Technical Note 12 Is Such a Big Deal

By Gordon Merrick, OFRF’s Senior Policy & Programs Manager

Versión en español a continuación.

The Need that Technical Note 12 Meets

The Natural Resources Conservation Service of the United States Department of Agriculture (USDA-NRCS, NRCS) has been one of the most impactful modern agencies in the adoption of conservation practices and systems in the United States. Only recently did the NRCS publish a technical note that will aid Field Agents and other Technical Service Providers (TSPs) administer these programs on organic operations. Technical Note 12 – Conservation Activities in Organic Farming Systems (Tech Note 12) provides a wealth of knowledge needed to effectively support the unique requirements of organic producers. Recently, as part of our work for the Transition to Organic Partnership Program (TOPP) in the West/Southwest region, we have developed a toolkit designed to raise awareness among farmers of this resource, which is now in the hands of NRCS staff and TSPs. In this blog post, we’ll briefly discuss what Tech Note 12 is, how it benefits farmers, and how it helps NRCS staff and TSPs.

What Is Tech Note 12?

A technical note, as defined by the NRCS, is an authoritative document designed to provide detailed guidance on specific technical subjects relevant to conservation planning and implementation. These documents serve as essential resources for NRCS field staff, TSPs, and producers, offering in-depth information and practical instructions to support the effective management of natural resources and address resource concerns. Technical notes are developed to address a wide range of topics, including soil health, water quality, wildlife habitat, and agricultural practices. They offer step-by-step procedures, best management practices, and innovative solutions to common challenges faced in the field. By standardizing and disseminating this knowledge, technical notes help ensure consistency and quality in applying NRCS conservation programs and practices.

Tech Note 12 is intended to provide all this information—as it relates to organic agricultural production. It offers detailed guidance on conservation activities that are compatible with organic standards and provides real-world examples that illustrate how conservation activities have been implemented.

How Tech Note 12 Helps Farmers

Tech Note 12 helps organic producers articulate the conservation benefits of their practices in the language used by NRCS field agents and TSPs. This clarity is crucial for accessing NRCS programs such as the Environmental Quality Incentives Program (EQIP) and the Conservation Stewardship Program (CSP), which provide financial and technical assistance to improve farm operations.

How Tech Note 12 Helps NRCS Staff and TSPs

For NRCS field agents and TSPs, Technical Note 12 is an invaluable tool for conducting thorough assessments of organic farming operations. By referencing the document, agents can identify appropriate conservation practices that address resource concerns while complying with organic standards. This approach ensures that the proposed solutions are both effective and aligned with the unique traits of organic farming, such as soil fertility, water management, pest control, and habitat conservation.

How to Access and Use Tech Note 12

To effectively use Tech Note 12 for your organic farming practices, start by contacting your regional Natural Resource Conservation Service (NRCS) office. Your NRCS field agent can provide helpful guidance on applying the recommendations in Tech Note 12 to your conservation planning while meeting organic standards.

For additional information and resources, download our Tech Note 12 flyer here. The flyer includes a summary of Tech Note 12, practical tips for using it, and suggested questions to ask your NRCS agent. This will help you get the most out of your NRCS support and prepare for your discussion.

Don’t miss out on valuable resources like this one—subscribe to our newsletter for groundbreaking organic farming research, educational guides, and critical funding and policy updates.

¿Por qué es tan importante la Nota Técnica 12?

La Necesidad que Satisface la Nota Técnica 12

El Servicio de Conservación de Recursos Naturales del Departamento de Agricultura de los Estados Unidos (USDA-NRCS, NRCS) ha sido una de las agencias más influyentes en la adopción de prácticas y sistemas de conservación en Estados Unidos. Recientemente, el NRCS publicó una nota técnica que ayudará a los Agentes de Campo y otros Proveedores de Servicios Técnicos (TSP) a administrar estos programas en operaciones orgánicas. Nota Técnica 12 – Actividades de conservación en sistemas agrícolas orgánicos (Nota técnica 12) proporciona una gran cantidad de conocimientos necesarios para apoyar de manera efectiva los requisitos únicos de los productores orgánicos. Recientemente, como parte de nuestro trabajo para el Programa de Asociación para la Transición a la Agricultura Orgánica (TOPP) en la región Oeste/Suroeste, hemos desarrollado un kit de herramientas diseñado para concienciar a los agricultores sobre este recurso, que ahora está en manos del personal del NRCS y los TSP. En esta publicación del blog, discutiremos brevemente qué es la Nota Técnica 12, cómo beneficia a los agricultores y cómo ayuda al personal del NRCS y a los TSP.

¿Qué es la Nota Técnica 12?

Una nota técnica, según lo define el NRCS, es un documento autoritativo diseñado para proporcionar orientación detallada sobre temas técnicos específicos relevantes para la planificación e implementación de conservación. Estos documentos sirven como recursos esenciales para el personal de campo del NRCS, los TSP y productores, ofreciendo información detallada e instrucciones prácticas para apoyar la gestión efectiva de los recursos naturales y abordar las preocupaciones de recursos. Las notas técnicas se desarrollan para tratar una amplia gama de temas, incluyendo la salud del suelo, calidad del agua, hábitat de la vida silvestre y prácticas agrícolas. Ofrecen procedimientos paso a paso, mejores prácticas de gestión y soluciones innovadoras a desafíos comunes enfrentados en el campo. Al estandarizar y difundir este conocimiento, las notas técnicas ayudan a garantizar la consistencia y la calidad en la aplicación de los programas y prácticas de conservación del NRCS.

La Nota Técnica 12 está destinada a proporcionar toda esta información, en lo que respecta a la producción agrícola orgánica. Ofrece orientación detallada sobre las actividades de conservación que son compatibles con los estándares orgánicos y proporciona ejemplos reales que ilustran cómo se han implementado las actividades de conservación.

Como la Nota Técnica 12 ayuda a los agricultores

La Nota Técnica 12 ayuda a los productores orgánicos a articular los beneficios de conservación de sus prácticas en el lenguaje utilizado por los agentes de campo y los proveedores de servicios de conservación del NRCS. Esta claridad es crucial para acceder a programas del NRCS como el Programa de Incentivos a la Calidad Ambiental (EQIP) y el Programa de Administración de Conservación (CSP), que de asistencia financiera y técnica para mejorar las operaciones agrícolas.

¿Cómo Ayuda la Nota Técnica 12 al Personal del NRCS y a los TSP?

Para los agentes de campo del NRCS y los TSP, la Nota Técnica 12 es una herramienta invaluable para realizar evaluaciones exhaustivas de las operaciones de agricultura orgánica. Al consultar el documento, los agentes pueden identificar las prácticas de conservación apropiadas que aborden las preocupaciones de recursos mientras cumplen con los estándares orgánicos. Este enfoque asegura que las soluciones propuestas sean tanto efectivas como alineadas con las características únicas de la, (agricultura orgánica) tales como fertilidad del suelo, manejo del agua, control de plagas y conservación del hábitat.

Cómo Acceder y Utilizar la Nota Técnica 12

Para utilizar eficazmente la Nota Técnica 12 en sus prácticas de agricultura orgánica, comience contactando a su oficina regional del Servicio de Conservación de Recursos Naturales (NRCS) (Oficina del Servicio Regional de Conservación de Recursos Naturales (NRCS) Su agente de campo del NRCS puede ofrecerte orientación útil sobre cómo aplicar las recomendaciones de la Nota Técnica 12 en su planificación de conservación mientras cumple con los estándares orgánicos.

Para más información y recursos, descargue nuestro folleto sobre la Nota Técnica 12 aquí. El folleto incluye un resumen de la Nota Técnica 12, consejos prácticos para su uso y preguntas sugeridas para hacerle a su agente del NRCS. Esto le ayudará a aprovechar al máximo el apoyo del NRCS y prepararse para su conversación.

No se pierda recursos valiosos como este: (Suscríbase a nuestro boletín) para recibir investigaciones innovadoras en agricultura orgánica, guías educativas y actualizaciones importantes sobre financiamiento y políticas.

By admin|2024-09-17T20:20:40+00:00September 13th, 2024|News, TOPP West|

A Call for Insights from Split and Non-Certified Operations

Our mission at OFRF is to “foster the improvement and widespread adoption of organic farming systems.” Organic certification has long been celebrated for its benefits to a variety of ecological and social systems; but we know that these benefits are not limited to fully certified organic farms. We understand that for a variety of reasons an operation will only have a portion of their land certified, or possibly forego certification entirely, but still operate as an organically-managed system. For those of you who manage operations like this, you have a unique perspective to observe and compare the impacts of organic practices across different types of land management systems.

We want to hear from producers like you about your relationship with and utilization of organic agriculture research. Research focused solely on conventional or chemical-based agriculture often cannot be applied to organic systems because it relies on inputs that are prohibited in organic farming. However, the opposite is not true: many organic practices can be beneficial for conventional farming operations as well. By understanding how split operations utilize organic principles, we can strengthen the case for increased funding in organic agriculture research that serves the entire agricultural community.

tractor driving across agricultural farm field

There are insights to gain from both split and non-certified organic operations about the benefits of organic.

Split Operations and the Potential of Organic Agricultural Systems

Split operations, where some fields are certified organic and others are managed using conventional chemistry- and genetic-based agricultural systems, provide an opportunity to offer valuable insights into the real-world application and benefits of organic farming practices and systems of management. This dual approach is a ripe opportunity for the observation of the effects of organic principles, such as cover cropping, complex crop rotations, reduced chemistry-dependance, and integrated pest management on their non-certified land.

We’re eager to hear your experiences and results from grasping this opportunity! The potential for healthier soils, increased resiliency of ecosystems, and even reduced input/fuel/labor costs is real.

Help Us Understand the Broader Impacts of Organic Research

Do you operate a split or non-certified operation that uses organic principles and systems? Do you know someone who does? We’re trying to hear from these operations to better understand how they might be using organic research in their decision making. Their experiences can help us better understand how organic agriculture research benefits the entire agricultural system, not just certified organic producers.

Quantitative analysis already shows that organic research benefits all of agriculture by developing methods that can improve soil health, enhance biodiversity, reduce input costs, and increase resilience against climate change. These benefits are not exclusive to certified organic farms—they are valuable to all farmers who are looking for sustainable, long-term solutions. Now we need your stories to make the qualitative points that illustrate these benefits!

Your Story Matters

Time and again, we hear in Washington that appropriators are hesitant to increase budgets for organic research programming because it is seen as too “niche” or doesn’t apply to all agricultural operations. If you or someone you know has a story to tell on this topic, it will be a crucial piece in helping us demonstrate the importance of organic agriculture research for the broader agricultural landscape.

Let’s work together to ensure that the benefits of organic agriculture are fully understood and leveraged for the good of all farming systems! Please reach out at gordon@ofrf.org.

Eat well and breathe deeply,

Gordon

By admin|2024-09-09T19:07:52+00:00September 9th, 2024|Gordon's Policy Corner, News|

Farmer Led Trials Program Spotlight: Salad Days Farm

Written by Mary Hathaway, OFRF’s Research & Education Program Manager

A female farmer in a purple coat smiles as the camera in front of rows of lettuce growing in a high tunnel.

Maggie Dungan, farmer at Salad Days Farm

Salad Days farm is a diverse vegetable operation situated on 30 acres in Versailles, Kentucky. Certified organic since 2015, farmer Maggie Dungan’s interest in growing food started with an education in nutrition and the long dream for her family to be self-sustaining. The farm grows year round in the field and in hoop houses to supply their on-farm store, restaurants, schools, and four weekly farmers markets.

Maggie works hard to keep mechanization on her farm minimal, focusing on cover cropping, minimal tillage, and other soil health conservation practices. She keeps only 2-4 acres of the farm in production, allowing her to focus on the quality of her systems to grow high value and sustainable food for her community.

Impact of Solarization on Soil Microbiology

The inside of a high tunnel, showing alternating rows of uncovered soil and soil covered with clear plastic for solarization research.

Solarization plots in the high tunnel.

Maggie was first exposed to the practice of solarization using clear plastic in 2022 when the farm participated in a research project with the University of Kentucky. The project studied the effect of solarization in high tunnels on root-knot nematode populations. She was impressed by the results of the trial, and saw first-hand how this technique impacted a persistent soil pathogen.

Organic farmers like Maggie that focus on minimizing tillage must still manage pathogens, weeds, and other common challenges, and solarization offers potential benefits. However, Maggie was concerned about the impact of the treatment on her soil health, and had some questions – if solarization kills pathogens, won’t it kill the good microbiology, too? How does heat smothering with a plastic tarp impact soil microbial activity? What is the impact on fungal to bacterial ratios?

Before beginning to incorporate soil solarization into her field plans, Maggie wanted some answers, and applied for OFRF’s Farmer Led Trial program to help her build out a solid research plan and find reliable results that would have a positive impact on her operation.

Farm trial plan

With technical support from OFRF, the Salad Days trial on soil solarization took shape. By refining her research question to: “What is the temporal and population effect of solarization on the beneficial microbes in the high tunnel?,” the research team was able to build an approachable and testable project on the farm.

Maggie and OFRF built out a block design with two treatments: No soil solarization in the hoop house, used as her control, or regular practice compared to soil solarization in the hoop house. Using her 30’x100’ hoop house as the location for the trial and mapping areas for the treatments, Maggie used a microbiometer to take three different soil samples: first a baseline reading, then one 2 weeks and 4 weeks, respectively, after the tarp had been removed from the treatment plots.

What is solarization?

Solarization is the process of placing a clear plastic tarp over a field or garden bed to heat up the soil underneath. The intention of solarization is to kill weeds or grass, but is also known to reduce pathogen populations in the soil.

On-farm trial updates

Maggie took her final soil reading in early August, four weeks after she removed the tarps from their beds. While she originally hypothesized that the soil microbes would bounce back, she guessed that their populations would need some time to recover after the tarp treatment.

8 bags of soil sit on a metal counter next to a soil testing kit.

Soil testing for the On Farm Trial.

The OFRF team has begun to work with the data collected to get an understanding of any significant differences. In Maggie’s experiment, we see that microbial biomass over time differed depending on whether or not the area had been tarped. Under solarization, microbial biomass increased over time, while biomass decreased over time in areas that had not been tarped. As well, the Fungal to Bacterial ratio was higher under solarization than bare soil. The ratio was not affected by time after tarp removal.

The data is compelling, and OFRF will be looking into similar research to better understand the why of these results and give Maggie the assurance she is looking for to deploy a practice that continues to foster the health of her soil and improve her farming system.

“Being able to tailor a research project specific to my farm but useful to all growers has been a great opportunity and having the technical assistance from OFRF has been integral.”

– Maggie Dungan, Salad Days Farm

A graph showing the microbial biomass in solarized and non solarized plots over time, with solarized plots higher than the control.

To learn more about soil solarization, check out these helpful resources on the web: https://extension.umn.edu/planting-and-growing-guides/solarization-occultation

To learn more about Salad Days Farm visit https://www.saladdaysfarm.com

Learn more about OFRF’s Farmer Led Trials Program

By admin|2024-09-10T18:26:23+00:00September 5th, 2024|Farmer Stories, FLT Highlight, News|

The Story of Diane Green and Greentree Naturals

Written by Elizabeth Tobey

Diane Green is a farmer, researcher, and educator, who has been tending the land at Greentree Naturals Farm in northern Idaho for over 30 years.

Nestled between the Cabinet and Selkirk Mountain ranges outside of Northern Idaho, just 60 miles south of the Canadian border, lies Greentree Naturals Farm. Diane Green and her husband, Thom Sadoski, have been tending this certified organic farm for over three decades. At its peak, this small farm had 2.5 acres in production. In recent years, as Diane and Thom have entered their 70s, they’ve downsized and are now actively farming one acre. They produce 130 varieties of certified organic vegetables, herbs, gourmet garlic, flowers, hops, and seeds—many of which are open-pollinated and saved annually. Their mission has always been clear: to build community through education, to model exemplary land stewardship, and to provide fresh, nutritious organic produce to their local community.

Over the years, Greentree Naturals has hosted numerous research projects in collaboration with local universities in Washington, Idaho, and Montana, and the Organic Seed Alliance. They’ve also received funding from OFRF and several of the major USDA research grant programs, including NIFA’s Organic Transition Program (ORG) and the Sustainable Agriculture Research and Education (SARE)—both programs OFRF works to bolster and protect through our advocacy work.

We spoke with Diane in the spring of 2024 about her experience as a farmer and the importance of research, collaboration, and community education.

Why Organic?

For Greentree Naturals, organic farming is more than a method—it’s a commitment to conservation and land stewardship. Reflecting on the broader impacts of climate change and environmental degradation, she emphasizes that everyone can contribute, regardless of their scale of operation.

“When I look at all the things happening with climate change and the desecration of the earth, it’s overwhelming,” Diane shares. “Growing organically is about making a commitment to practicing conservation and land stewardship, and it’s something that everyone can commit to, whether they have a few grow boxes or a one-acre market garden, or hundreds of acres of food production.”

This commitment is reflected in every aspect of Greentree Naturals, from their diverse crop offerings to their sustainable farming practices and their continuous participation in organic agriculture research and education activities on their farm.

Challenges and Adaptation

Organic crops growing in the fields at Greentree Naturals.

Farming in Northern Idaho presents unique challenges, particularly with the increasingly unpredictable weather. Over the years, Diane and Thom have kept detailed notes and observed significant changes in weather patterns, including more extreme conditions, such as 90-degree days in May dropping to freezing temperatures overnight. These conditions necessitate season extension techniques and constant adaptation. “Everything I thought was normal has changed,” Diane notes. Planning for these extremes and embracing flexibility is key to success. “I tell my gardening students that as long as you plan for the hottest, coldest, wettest, driest growing season in recorded history, you’ll be ready to grow in North Idaho. But I suppose that’s probably the same for growing everywhere anymore.”

Diane underscores the importance of on-farm research in observing these changes and developing adaptive strategies. “On-farm research [is] a way to help people focus on documenting those changes, and working together through partnerships to find solutions to adapt to those challenges,” she says.

As the growing seasons become hotter, Diane and Thom have noticed new pests showing up. “We’ve had new beneficials too,” Diane notes. “Last year, we saw praying mantises showing up, which we’ve never had before.” But the new types of pests can be alarming and present a challenge. The farm now has three types of wireworms which were not present before. “The grad student that was specializing in wireworms was thrilled about it, we’re not so much,” Diane says with a laugh. As these variables come into play, Diane highlights the importance of clear observations and documentation. “As farmers, we’re always watching,” she says, adding that participating in research can make a difference in how you see things. “It makes you focus,” she says. “I like that.”

Conservation Practices

Greentree Naturals produces 130 varieties of certified organic vegetables, herbs, gourmet garlic, flowers, hops, and seeds.

At Greentree Naturals, healthy soil is the cornerstone of their farming philosophy. Diane emphasizes the importance of thinking about soil as a living entity. “The more we learn, the more we know we have to learn about growing healthy soil,” she says. The farm employs a variety of practices to enhance soil health, including reduced tillage and cover cropping, utilizing mustard as a main cover crop because it germinates and grows well in a variety of conditions. They also utilize worm composting and make their own compost, supplemented with OMRI-approved chicken manure-based compost when necessary.

Intimately related to soil health, water quality and biodiversity are critical to their conservation efforts. Greentree Naturals is bordered by wild lands, leading to frequent encounters with local wildlife such as black bears, grizzlies, deer, and elk. Diane incorporates these animals into the pest management workshops she teaches, discussing how to coexist collaboratively with nature.

Research and Education

Greentree Naturals has been a hub for numerous research projects and Diane’s passion for education is evident in her extensive involvement in on-farm research and community education. She contracts with the Oregon State University and the University of Idaho as a consultant, advisor, and farmer-educator. She is also one of the founders of the Cultivating Success Small Farms Education Program and a mentor with the USDA Transition to Organic Partnership Program (TOPP) with Oregon Tilth.

Thom and Diane both have backgrounds collecting field data for the USFS, and were taught early on the importance of recording accurate field information. Their fields are mapped with numbered rows and easy-to-identify locations of plots, specific crops, and field applications. And, because they are a certified organic farm, they are required to maintain clear records of everything they do in the fields.

The farm has been a host site for a variety of research projects, including:

Efficacy Evaluation of Biological Control Agents Against Wireworms in Organic Production
Soil Health and Fertility Testing to Optimize Organic Carrot and Beet Production in Northern Idaho
Biodiversity and Natural Pest Suppression
Extension of Local Food Production in Idaho Using High Tunnel Technology
Combining Trap Cropping with Companion Planting to Maximize Control of the Crucifer Flea Beetle in Organic Mixed Vegetable Farms
On-Farm Variety Seed Trials for Organic Systems

Detailed information about the research projects is available on the farm’s website.

Hosting field days is an important part of community engagement and education at Greentree Naturals farm.

Diane believes strongly in the necessity of these research collaborations. “It’s really important with agriculture research that it’s duplicated on a farm and doesn’t only happen in a controlled university site,” she asserts. “The more we cultivate partnerships between universities and on-farm research, the better.”

Hosting field days has also become a substantial part of how Greentree Naturals promotes farmer education and networking. They’ve had to cap attendance for these events, which often sell out.

“Field days are a wonderful opportunity to network with other farmers, community members, and researchers,” Diane says. “We’ve so enjoyed hosting those at our farm.” They’ve found that the format of a Sunday afternoon event that includes lunch works well for them and their farming community. “Farmers want to learn from farmers,” Diane states, noting that they are always sure to pair a farmer with an extension educator or researcher so that the two perspectives can be shared side-by-side.

Engaging Farmers in Grant Funded Research

Diane believes on-farm research is a critical component of successful organic research and innovation.

Grant-funded research has played a significant role in the farm’s ability to conduct meaningful research. Diane was quick to note that the money is not the only reason they have participated in research projects; they have donated hundreds of hours and production space to research projects. But as Diane says, it’s much more sustainable for farmers to participate in research when their contributions are honored. “It’s much easier to let go of a production area for research if you’re compensated,” she explains. She notes that too often grantees come to the farmers after a grant is already written. She strongly encourages researchers and extension staff to engage farmers in the grant-writing process from the beginning to ensure that adequate compensation that respects the farmers is written into the proposal.

Diane encourages other farmers to engage in on-farm research and to utilize existing resources and partnerships, noting that “as farmers, we are constantly experimenting and testing our ideas.” But, she says, “it’s important to remind ourselves we don’t have to reinvent the wheel.” There are lots of resources available from sources like OFRF, SARE, and others. Diane also recommends forming partnerships with local extension educators. “Don’t try to do these things alone,” she advises.

University students assist with an on-farm research trial.

“Applied research and partnerships are crucial,” Diane continues, emphasizing the broader importance of collaboration and community in agricultural research. “As farmers, we tend to be pretty isolated, and we tend to want to put our heads down and do what we’re doing,” Diane admits. “But I think ideally one of the best things we can be doing for ourselves and for the planet is working together and building partnerships through the agricultural community.”

By forming partnerships and engaging in applied research, farmers can achieve more significant and impactful results, benefiting both their operations and the broader agricultural community. “It’s going to take all of us working side by side,” Diane states.

Looking Forward

As Diane and her husband begin to downsize their operations, she has concern for the future of agriculture, particularly the loss of farmland to development and the challenges new farmers face.

“There needs to be a new model for farmland succession, especially in organic farming,” she urges. Diane envisions a future where farmland is preserved for new generations of farmers, ensuring that the biodiversity and sustainability practices they have cultivated at Greentree Naturals continue to thrive, while also supporting aging farmers in their retirement.

Conclusion

Diane Green’s story is one of hope, resilience, and unwavering commitment to organic farming and community education. Through her work at Greentree Naturals, she demonstrates that sustainable farming is not only possible but essential for the health of our planet and our communities. Her message is clear: by working together, farmers, researchers, and educators can create a more sustainable and equitable agricultural system for future generations.

Make sure you never miss a Farmer Story like Diane’s from OFRF by signing up for our newsletter here. Do you know a farmer whose story should be featured? Fill out this short form to let us know about them.

By admin|2024-08-27T17:33:14+00:00August 27th, 2024|Farmer Stories, News|

What Research Tells Us

Written by Mark Schonbeck and OFRF staff

We recently launched a new newsletter section, “Ask OFRF,” a place where our community can submit questions for our staff to answer. Our first question came from Brian Caldwell of Hemlock Grove Farm, a certified organic farm in NY.

The life within our soils provides the foundation for successful farming and all terrestrial ecosystems. The diverse community of soil organisms—bacteria, fungi, protozoa, worms, and more—forms what we now call the soil food web. This web of life converts fresh residues into soil organic matter (SOM) and supports essential soil functions critical for agricultural production. Ever since the early 20th century, pioneers of organic agriculture like Sir Albert Howard and Ehrenfried Pfeiffer understood that “if you feed the soil, the soil will feed the plant.” Yet, despite their insights, mainstream agricultural science of the time often overlooked the vital role of soil life in plant nutrition.

In recent decades, extensive research has begun to illuminate how an optimally functioning soil biota feeds crops, enhances resilience, protects water quality, and contributes to long-term farm viability. However, concerns about the impact of agrochemicals, including herbicides and synthetic fertilizers, on soil health and soil life remain pressing.

Recently an important question was raised:

“Do you know if there is much research on the impacts of herbicides and synthetic fertilizer on SOM or soil health? Organic pioneers reported that soil health declined under chemical fertility management. For reasons that are not clear to me, some scientists discount the Morrow plot findings of Khan et al (2007), which support that. Do you have other research reports on that topic?”

To address this, we turned to OFRF’s Senior Research Associate, Mark Schonbeck. A respected researcher and long-time advocate for organic farming systems, Mark has dedicated his career to exploring the complex interactions between soil management, crop resilience, and farm sustainability. With his extensive knowledge, Mark offers valuable insights into the impacts of herbicides and synthetic fertilizers on SOM and overall soil health. Here’s what he has to say (all resources can be found at the end of this post):

Expert Insights from Mark Schonbeck on Soil Health

There is a growing body of research showing that all classes of crop protection chemicals (insecticides, fungicides, herbicides, nematicides, etc.) adversely affect all major taxa of soil organisms. From prokaryotes (bacteria and archaea) and fungi through nematodes, micro-arthropods (mites, springtails, etc), earthworms, and more, the soil biotic community is harmed by chemical applications. In fact, routine use of conventional agricultural chemicals have shown greater negative impacts on soil microbiomes than routine tillage in several recent meta analyses.

As for synthetic fertilizers and the Khan and Mulvaney analyses out of the University of Illinois, those papers (this one and this one) included not only the results from the Morrow plots themselves but also a review of a large number of other medium to long-term (5-100+ year) farming systems trials around the world. I used to emphasize those findings, which show that adding synthetic Nitrogen (N) undermines soil carbon sequestration as clear evidence that synthetic Nitrogen, Potassium, Phosphorous (NPK) fail to build Soil Organic Matter (SOM) despite higher crop biomass, and even sometimes burns up SOM.

In a 2023 personal conversation, Dr. Ray Weil of University of Maryland (whom I respect highly as a world-class soil scientist) raised concerns about the reliability of the Khan and Mulvaney papers during a National Institute of Food and Agriculture (NIFA) project meeting (for OREI and ORG) in Washington, DC in 2023. He shared that the studies are being questioned because those showing negative impacts of soluble NPK on SOM may have been selectively chosen in the literature review while those showing positive or neutral effects were de-emphasized. Recent research suggests that soluble fertilizer used along with organic inputs can build SOM and I believe that it is more a matter of what soluble fertilizer by itself lacks and not what it contains that can harm soil life. Recent research suggests that it’s not the presence of soluble nitrogen itself that harms soil health, but rather the imbalance between N and organic carbon inputs.

If a farmer is providing lots of organic inputs (high biomass cover crops, compost, etc.) and then uses some synthetic N or NPK, the yield increase elicited by the synthetic fertilizer can indeed improve SOM accrual. There was at least one meta-analysis comparing organic, organic + synthetic, and synthetic-only fertilization on microbial (fungal and bacterial) biomass. The result was: organic ~ organic + synthetic >> synthetic only (with a highly significant two-fold difference).

When it comes to fertility and nutrient sources and soil life or SOM, it is a matter of balance between organic carbon inputs and nitrogen inputs (whether organic and/or synthetic). When there is sufficient organic carbon (C) and the C:N ratio is balanced (~15-25:1), the soil life thrives and microbial biomass and respiration increase, as does the formation of stable mineral-associated organic matter (MAOM) and more labile or active particulate organic matter (POM)—both important to the functions of healthy soil.

If the C:N ratio is too narrow (for example poultry litter is 7:1), less SOM accrues and the soil microbiome is less capable of cycling N to ensure crop nutrition while minimizing leaching and denitrification losses. In an organic systems study, researchers at Washington State University found that vegetable rotations fertilized with compost (C:N ~20) accrued much more SOM (active and total) and sustained higher microbial activity and function than vegetable rotations fertilized with poultry litter (7:1) at the same total N rate. Crop yields were similar in the two systems. (More on that here).

In conclusion, the intricate relationship between chemical inputs, soil health, and agricultural productivity is a complex one. As research continues to illuminate the complexities of soil ecology, the importance of organic practices in preserving this vital resource becomes increasingly apparent. To foster sustainable agricultural practices, a holistic approach is essential. A transition to more organic and regenerative agricultural systems is essential for ensuring the health of our planet and future generations. Prioritizing soil health through practices like cover cropping and organic matter incorporation is crucial for long-term agricultural success. By understanding the complex interactions between soil organisms, nutrients, and crop production, we can develop strategies to enhance both yield and environmental sustainability.

A Deeper Dive: Key Studies and Findings

The following is a series of excerpts from a webinar Mark gave on Soil Disturbance, where he dives more into each of these topics, including specific studies that are relevant to this question.

The Case of Glyphosate: making sense of conflicting results

While the overall impact of pesticides on soil health is clear, the specific effects of individual chemicals can be more nuanced. Glyphosate, the most widely used herbicide in conventional agriculture across the world, is a prime example of this complexity.

There are plenty of studies showing everything from no harmful effect to subtle yet alarming disruptions to plant physiology, soil microbiology, or ecosystem functions due to glyphosate applications. Here are a sample of findings:

Experiments were conducted within long-term farming systems trials at Beltsville, MD and Stoneville, MS to determine whether foliar applications of glyphosate at normal rates (two applications at 0.75 lb active ingredient per acre) would affect rhizosphere microbiomes (Kepler et al., 2020). Glyphosate-resistant (GR) corn and soybean cultivars were planted in plots with (conventional) or without (organic at Beltsville, unsprayed perennial grass at Stoneville) a history of glyphosate use, and either foliar-sprayed with the herbicide or left untreated. Root and root zone soil samples collected 20 days after treatment showed no differential effect of glyphosate sprays on endophytic, rhizosphere, or bulk soil microbiomes (Kepler et al. 2020).
Field applications of glyphosate at 1⁄4 and 1X recommend rates sharply (>80%) reduced the spore viability of arbuscular mycorrhizal fungi (AMF) in soil samples collected 10 or 30 days after field application and reduced the ability of AMF to form functional arbuscules in ryegrass (Lolium multiflorum) roots (Druille et al., 2013).
Application of glyphosate at roughly half-label rates to orchard grass, dandelion, or white clover growing in greenhouse mesocosm trials (large pots, 12-gallon capacity) significantly reduced the activity and reproductive success of two earthworm species (Lumbricus terrestris and Apporectodea caligenosa) that were introduced into the pots five weeks before treatment (Gaupp-Berghausen et al., 2015). Herbicide treatment also caused a sharp increase in soluble soil N and a slight increase in soluble P. Field studies would be needed to clarify the practical implications of these greenhouse observations for earthworms, soil health, and water quality in agricultural production.
A study of the prevalence of wheat head blight caused by two species of Fusarium in wheat production in Saskatchewan showed an apparent positive association between the disease and a history of glyphosate use (Fernandez et al., 2009).
Ten years of field trials in Missouri showed significantly increased root colonization by Fusarium fungi of glyphosate-resistant corn and soybean treated with the herbicide compared to the same crop cultivars without herbicide treatment. Glyphosate treatment also appeared to affect soil microbes involved in manganese (Mn) availability, N fixation, and disease suppression (Kremer and Means, 2009). It is notable and surprising that this trial gave such different results from Kepler et al. (2020). One possible factor is different regions and soil types. In a review of 67 published studies of the impacts of herbicides on soil invertebrates (arthropods, earthworms, pot worms, and nematodes), 77% of “tested parameters” studied in lab experiments and 32% of parameters in field conditions showed negative impacts (Gunstone et al., 2021).

Glyphosate showed adverse effects in some studies, and no effect in others, and appeared less damaging to soil life than amide/anilide herbicides and most insecticides and fungicides. Possible mechanisms of glyphosate effects on soil life include direct exposure via spray reaching the soil surface or translocation of the chemical from sprayed foliage to the root system, changes in the physiological condition of treated plants that curtail or alter the composition of root exudates including chemical signals, and long-term effects of low-level herbicide exposure year after year. One concern is that, given its frequent and widespread use and sometimes overuse, glyphosate may exert significant agroecosystem impacts despite its relatively low toxicity compared to other crop protection chemicals.

Pesticide Impacts on Soil Organisms: A Quantitative Perspective

To gain a clearer picture of the extent to which pesticides affect soil organisms, it is essential to examine quantitative data from multiple studies. A recent meta-analysis provides valuable insights into this complex issue. The following is another excerpt from the Soil Disturbance webinar:

In an extensive review of 398 studies that included a total of 2,842 tested parameters, Gunstone et al. (2021) evaluated the impacts of five classes of crop protection chemicals—insecticides, herbicides, fungicides, bactericides, and mixtures of two or more chemicals—on a wide range of soil invertebrates including nematodes, annelids (earthworms and pot worms), and arthropods (mites, springtails, insects, centipedes, etc). The authors defined a “tested parameter” as the chemical’s effect on one aspect of the health of one species or larger taxonomic group of soil organisms—the survival, growth, reproduction, or a behavioral or physiological function of the organism studied. Most studies addressed multiple organisms and/or multiple indicators of pesticide impacts on a single organism. All classes of pesticides affected all groups of organisms with negative impacts found in 70% of tested parameters. Lab studies found negative impacts more often (81%) than field trials (53%), and the field studies found more negative impacts of insecticides (61%) than fungicides (38%) or herbicides (32%). Earthworms were the most widely studied organisms (1,321 tested parameters) and showed sensitivity to all classes of agrochemicals including insecticides (82%), fungicides (78%), and herbicides (72%).
Researchers have documented significant impacts of corn and soybean seed treatments (fungicides and neonicotinoid pesticides) on the crop rhizosphere microbiomes (bacteria and fungi) and on several trophic levels of the soil fauna (Atwood et al., 2018; Nettles et al., 2016). Neonic seed treatment had a greater impact on non-target soil organisms, especially predatory and mixed-feeding guilds, while having relatively little impact on the target herbivore (pest) species.
In laboratory studies, mixtures of Mesotrione and S-metolachlor herbicides degraded more slowly and exerted a tenfold greater impact on soil microbial biomass and activity than either herbicide alone (Joly et al., 2012). A similar synergism related to enhanced persistence was documented for diflufenican and glyphosate (Tejada, 2009).

Balancing C:N for optimal soil health

To optimize soil health and crop productivity, it is essential to consider the balance of nutrients provided to the soil. The following research explores how different nutrient management strategies impact soil microbial communities and overall ecosystem function.

Based on five meta-analyses, Young et al. (2022) found that fertilizer regimens that combined organic and soluble N sources supported at least as much SOC accrual (1.3% per year) as all-organic N fertilization. The combination reduced leaching and NH3 volatilization by 28% (intermediate values between all organic and all soluble N treatments), but eliminated the increase in N2O emissions seen with all-organic sources.
In a long-term (10-year) greenhouse vegetable production trial, substituting half of the soluble NPK inputs with organic nutrient sources (manure, straw, manure + straw) enhanced soil taxonomic and functional microbial diversity, and specifically promoted the diversity and function of soil microbes involved in P cycling, resulting in greater P mineralization for crop uptake and at the same time holding excess P against leaching or runoff losses (Zhang et al., 2022b).

These findings suggest that soluble N sources disturb the soil microbiome not because of what they contain (nitrate, ammonium, urea) but because of what they lack—organic carbon. Soil microbes thrive on a balanced mixture of organic carbon and nitrogen, and soil health can suffer under organic management if C and N inputs are not balanced. This was clearly illustrated in an 11-year organic vegetable farming systems trial conducted in Washington State comparing plots fertilized with poultry litter (C:N ~7) versus finished compost (C:N ~ 20) at equivalent total N rates. While the two treatments gave similar crop yields, the compost-amended soil had 43% higher total SOC, 65% higher active SOC, and 35% higher microbial activity than the poultry litter-amended soil (Bhowmik et al., 2016, 2017).

The evidence presented underscores the critical role of organic agriculture in safeguarding soil health. By eschewing synthetic pesticides and fertilizers, organic systems inherently protect soil biota from harmful chemicals, fostering a thriving ecosystem beneath the surface. The emphasis on organic matter inputs in organic farming is crucial for building soil structure, enhancing water retention, and providing a steady supply of nutrients.

Mark Schonbeck has worked for 37 years as a researcher, consultant, and educator in sustainable and organic agriculture. He has participated in on-farm research into mulching, cover crops, minimum tillage, and nutrient management for organic vegetables. For many years, he has written for the Virginia Association for Biological Farming newsletter and served as their policy liaison to the National Sustainable Agriculture Coalition. He has also participated in different research projects to analyze, evaluate, and improve federally funded organic and sustainable agriculture programs. In addition, Mark offers individual consulting in soil test interpretation, soil quality and nutrient management, crop rotation, cover cropping, and weed management. He has worked with OFRF as a research, education, and policy consultant for many years.

For more from Mark on this topic, you may be interested in checking out the Conservation Agriculture Webinar Series he presented, which we hosted in partnership with the NRCS: https://ofrf.org/news/conservation-ag-webinars/

References

Baas, D. G., G. P. Robertson, S. R. Miller, N. and Millar, N. 2015. Effects of Cover Crops on Nitrous Oxide Emissions, Nitrogen Availability, and Carbon Accumulation in Organic versus Conventionally Managed Systems. ORG award 2011-51106-31046. https://nifa.usda.gov/data/data-gateway.

Berthong, S. T, D. H. Buckley, and L. E. Drinkwater. 2013. Agricultural management and labile carbon additions affect soil microbial community structure and interact with carbon and nitrogen cycling. Microbial Ecology 66: 158-170.

Bhowmik, A. A-M. Fortuna, L. J. Cihacek, A. Bary, P. M. Carr, and C. G. Cogger. 2017. Potential carbon sequestration and nitrogen cycling in long-term organic management systems. Renewable Agriculture and Food Systems, 32 (6): 498-510.

Bhowmik, A., A. Fortuna, L. J.Cihacek, A. I.Bary, and C. G.Cogger. 2016. Use of biological indicators of soil health to estimate reactive nitrogen dynamics in long-term organic vegetable and pasture systems. Soil Biology and Biochemistry 103: 308-319.

Bowles, T. M., A. D. Hollander, K. Steenwerth, and L. E. Jackson. 2015. Tightly-Coupled Plant-Soil Nitrogen Cycling: Comparison of Organic Farms across an Agricultural Landscape. PLOS ONE peer-reviewed research article. http://journals.plos.org/plosone/article?id=10.1371/journal.pone.013188l

Brennan, E. 2018. Lessons from long-term, cover crop research in the Salad Bowl of the World – 10 minute youtube video, https://www.youtube.com/watch?v=JurC4pJ7Lb4

Brennan, E. B., and V. Acosta-Martinez. 2017. Cover cropping frequency is the main driver of soil microbial changes during six years of organic vegetable production. Soil Biology and Biochemistry 109: 188-204.

Carr, P. M, M. A. Cavigelli, H. Darby, K. Delate, J. O. Eberly, H. K. Fryer, G. G. Gramig, J. R. Heckman, E. B. Mallory, J. R. Reeve, E. M. Silva, D. H. Suchoff, and A. Woodley. 2020. Green and animal manure use in organic field crop systems. Review article. Agronomy Journal 112 (2): 648-674.

Cogger, C. G. M. Ostrom, K. Painter, A. Kennedy, A. Fortuna, R. Alldredge, A.; Bary, T. Miller, Collins, J. Goldberger, A. Antonelli, and B. Cha. 2013. Designing Production Strategies for Stewardship and Profits On Fresh Market Organic Farms. OREI award 2008-51300-04460. https://nifa.usda.gov/data/data-gateway.

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By admin|2024-09-09T18:08:29+00:00August 19th, 2024|News|

Balancing Soil Health and Weed Management in Organic Farming

By Thelma Velez and Heather Estrada

Organic farmers are often praised for their commitment to environmental stewardship. Indeed, these growers must adhere to rigid standards set forth through the National Organic Program, which delineates what is (and is not) allowed on organic operations. These standards are key to ensuring that the certified organic label is the same across the country. While many argue there is room for improvement in the label (and its enforcement), one thing is certain—farms under organic management are more ecologically sustainable than conventional operations. Organic farms are better for the environment, better for the people, and better for the planet.

Mattawoman Creek Farm in Virginia uses a permanent raised bed system to eliminate soil compaction. Photo used with permission from www.mattawomancreekfarms.com

That said, organic farmers also face extensive criticism regarding their use of tillage. There is no denying that excessive or poorly timed tillage can lead to soil erosion or nutrient run-off, and there is mounting evidence that tillage can disturb fungal networks, harm larger soil organisms, and increase the decomposition of soil organic matter (SOM). However, it is worth “digging in,” “turning over,” and “exposing” why organic farmers till in the first place and how tillage practices and outcomes differ.

Why Do Organic Farmers Till?

So why do organic farmers till? In 2022, we published our National Organic Research Agenda (NORA) report. Organic farmers across the country indicated that their number one production challenge is managing weeds on their farms (Snyder et al., 2022). Tillage in organic systems is used for a variety of reasons, including weed management, but also for terminating cover crops or preparing seedbeds. While conventional growers use synthetic herbicides to terminate weeds, organic farmers are not allowed to apply these chemicals to the soil, nor would they want to, given the extensive evidence of the harm these chemicals cause to both humans and ecosystems.

Building and maintaining healthy soil is the key for most successful organic farming operations (yes, this includes dairy and livestock operations where animals graze on pasture). Thus, co-managing soil health while also tackling weeds is something organic farmers deal with on a regular basis. Interestingly, there are researchers and farmers who have been studying soil for decades to better understand the impacts of tillage on different parameters of soil health, and what we are learning is that not all tillage is created equal. In fact, there are organic farms across the country that have been finding ways to keep weeds at bay while also improving soil health.

The science of the last decade has begun to unravel some of the complexities related to how tillage depth and intensity affect soil organisms and soil organic carbon.

Impact of Tillage on Soil Health

Amanda Gillett uses a no-till drill on her farm in Montana to eliminate tillage to save moisture and build soil health. Original public domain image from Flickr.

Studies have documented improvements in active soil organic carbon (SOC) and other soil health parameters when combining cover crops and compost applications, even with tillage (Cogger et al., 2013; Delate et al., 2015). Results from six long-term farming systems trials with organic crop rotations that included legume cover or sod crops, organic nutrient sources (compost or manure), and routine tillage actually accrued significantly more SOC than conventional corn-soybean rotations (Delate et al., 2015).

Variability in Tillage Methods

Tillage is not a one-size-fits-all approach. There are major differences between deeper inversion tillage and shallow non-inversion tillage. In one meta-analysis, shallow inversion tillage resulted in higher soil carbon, more effective weed control, and only minimal yield reductions when compared with deeper tillage (Cooper et al., 2016).

More invasive approaches, such as a moldboard plow, disk plow, or chisel plow at depths greater than six inches, will inherently create more disturbance, but taking a more shallow and judicious tillage approach is generally less harmful to soil health and can be compatible with soil building goals (Schonbeck et al., 2017; Dimitri et al., 2012).

Additionally, there are meta-analyses with promising findings related to enhanced soil life in reduced tillage systems (Chen et al., 2016; Li et al., 2020; Morugán-Coronado et al., 2022). Morugán-Coronado’s 2022 paper also included findings showing that reduced tillage systems outperformed full-tillage and no-till with respect to increases in microbial and fungal biomass (Morugán-Coronado et al., 2022).

Balancing Tillage and Soil Health in Organic Farming

While tillage is an essential tool in organic farming, its impact on soil health is complex and varies depending on the method and intensity used. The evolving science of soil management suggests that organic farmers can adopt practices that minimize soil disturbance while addressing production needs. This balanced approach helps to preserve and enhance soil health, supporting the overall sustainability of organic farming systems.

For more information on balancing tillage and soil health, check out our guidebook “Practical Conservation Tillage,” which provides a practical means to reduce tillage and protect soil organic matter, soil life, and tilth through green manures, compost applications, and other organic practices.

Download Practical Conservation Tillage Guidebook

How do you manage tillage in your farming practices? Email us at info@ofrf.org to share your experiences and insights, and stay informed about the latest research to continually improve your soil management strategies by signing up for our newsletter here.

References

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Cooper, J., Baranski, M., Stewart, G., Nobel-de Lange, M., Bàrberi, P., Fließbach, A., Peigné, J., Berner, A., Brock, C., Casagrande, M., Crowley, O., David, C., De Vliegher, A., Döring, T. F., Dupont, A., Entz, M., Grosse, M., Haase, T., Halde, C., … Mäder, P. 2016. Shallow non-inversion tillage in organic farming maintains crop yields and increases soil C stocks: a meta-analysis. Agronomy for Sustainable Development, 36, 22. https://doi.org/10.1007/s13593-016-0354-1

Delate, K., C. Cambardella, and C. Chase. 2015. Effects of cover crops, soil amendments, and reduced tillage on Carbon Sequestration and Soil Health in a Long Term Vegetable System. Final report for ORG project 2010-03956. CRIS Abstracts

Dimitri, C., L. Kemp, J. Sooby, and E. Sullivan. 2012. Organic Farming for Health and Prosperity https://ofrf.org/wp-content/uploads/2019/09/HP-report-web.pdf

Li, Y., Q. Zhang, Y. Cai, Q. Yang, S.X. Chang. 2020. Minimum tillage and residue retention increase soil microbial population size and diversity: implications for conservation tillage. Sci. Total Environ., 716, 137164.

Morugán-Coronado et al., 2022. Agric., Ecosystems & Envir. 329, Article 107867. Meta-analysis.

Schonbeck, M. D. Jerkins, and J. Ory. 2017. Soil Health and Organic Farming: Practical Conservation Tillage. https://ofrf.org/wp-content/uploads/2019/09/HP-report-web.pdf

By admin|2024-08-12T20:50:15+00:00August 12th, 2024|News|