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young soybeans

Results are available online for the 2019 Michigan Organic Soybean Variety TrialsThe trials included 43 varieties – 20 of which are commercially available. Results include details on source, variety, maturity group, hilum color, percent oil, percent protein, maturity days after planting, plant height, yield and multi-year data.

Previous years’ organic trials for soybeans, edible beans, and other agronomic crops can be found at the Organic Farmers of Michigan website.

Ohio State Corn and Oats Variety Trials Planned for 2020

Ohio State is planning organic crop variety trials this year for both corn and oats. Organic farm manager Gerald Reid reports 15 varieties of oats have emerged and that corn trials should be planted soon.

Previous Ohio State organic corn variety trials can be found online as well:

2019 Organic Corn Variety Trials

2018 Organic Oat Variety Trials

2017 Organic Oat Variety Trials

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Microbe-containing industry overview

Biostimulants are not exclusive to organic systems, but they are a common input for organic growers. Ohio State vegetable production specialist Matt Kleinhenz has spent many years studying microbial-based biostimulants (MBBS). Few agricultural input markets have seen the kind of explosive growth that has occurred with MBBS.

“These products are widely available, relatively inexpensive, are said to offer interesting and appealing benefits, and rarely put users at significant risk, unlike some other products,” says Kleinhenz.

Nicole Wright, program coordinator for the Vegetable Production Lab’s MBBS project, also attributes market growth to increased interest in microbiology.

“I think growers are applying them and thinking about soil and soil microbiology,” she says, “They are thinking ‘everything I hear says that having healthy soil means having lots of living things in them and if I can contribute to that, it’s a good thing.’”

With a constant stream of products entering and exiting the market, Kleinhenz and his team are less interested in testing specific products and more interested in answering the bigger questions surrounding this subset of agricultural inputs. Their research has focused on identifying which factors are important to product efficacy, such as the effect of timing and application rate.

Kleinhenz and Wright have this advice for growers interested in or already using MBBSs on their crops:

  • Do background research. Just because a product is OMRI-listed does not mean it’s been found effective. Set aside time to read up on the product. Take a critical look at label instructions. What details are provided about the timing, application rate and application methods? What can the manufacturer tell you about mixing it with other products or using it in specific conditions or crops?
  • Be wary of claims that seem exaggerated. Most of these products create modest, gradual, and/or inconsistent yield improvements. Growers should have realistic expectations for MBBS products.
  • Product consistency can be an issue with MBBSs. If a product only works some of the time, the cause may be related to the user, the manufacturing process and product itself, or production conditions. For example, environmental factors like soil fertility, pH, or cropping history might influence  the product’s effectiveness.
  • Use storage and handling procedures that acknowledge these are living products. Avoid temperature extremes and chlorinated water, for example.
  • Track what happens. Referrals from other users of the product are valuable. But remember that their success won’t necessarily be repeated in your farm’s unique conditions. When trying a new product or practice, maintain a similar untreated part of your field to compare. Do your own experiments with rate and timing. Keep records on what you applied, where, and take notes on any differences you see in growth, yield, quality, etc.
  • Use good cultural processes to increase microbials in your soil too. Wright likens MBBS products to taking a vitamin vs. eating healthy foods. Cultural practices that favor soil biodiversity, organic matter, and good drainage are also needed to provide food and conditions that allow microbial life to thrive.

Change is coming

So far, these products are largely unregulated. For the first time, the current farm bill includes language defining a biostimulant--an important first step in creating better uniformity in the industry, says Kleinhenz. Some manufacturers are concerned about the overall image of MBBS products and are pushing for a more narrow definition along with efficacy testing.

Kleinhenz feels regulation will usher in increased product consistency and better information for consumers, but regulation may also limit the number of products available. Testing product efficacy requires time, expertise, and/or expenses that smaller manufacturers may find challenging.

He also questions if it is truly appropriate to apply the same efficacy standards used for many mainstream agricultural inputs. Based on averages and standard, proven statistical analysis, a comparison of treated and non-treated plots failed to show that inoculation (product use) significantly influenced yield. However, the Vegetable Production Systems Lab team observed many times when a MBBS did increase yield (and a few times when it lowered it).

“If you went out to your truck and it only started half of the mornings, you’d be pretty annoyed and conclude it’s unreliable, that it’s not working,” Kleinhenz says. “However, if you apply a product to your crops or soils and see measurable improvement say, 30% of the time, you might still find the application worthwhile if the costs and other risks were low. Our goal as a team is to provide growers and others with information they can use to distinguish worthwhile from unwise investments and practices.”

There are many additional practical questions to answer that could involve microbiology and decision-making. For now, Kleinhenz and his lab are enjoying the conversation and questions stimulated by this growing and changing industry. 

Read more at: https://u.osu.edu/vegprolab/research-areas/vegebiostimsferts/

This research is supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, Organic Transitions Program under award Number 2016-51106-25714 and also under award number 2016-38640-25381 through the North Central Region SARE program under subaward number LNC16-380.

In-person Ohio State Extension events scheduled for March and early April are being canceled due to coronavirus concern. County extension offices will also be closing, but Ohio State employees continue to work remotely and can be reached by email. Read more here. 

The Wood County Transition to Organic Grains workshop originally scheduled for April will be rescheduled for a safe and appropriate date.

Ohio State Resources for Coronavirus 

Questions Regarding the Novel Coronavirus (COVID-19) on Farms with Employees
(pdf – English) 
(pdf – Spanish)

Mitigating Immediate Harmful Impacts of COVID-19 on Farms and Ranches selling through Local and Regional Food Markets (pdf)

Tax Implications for Farmers (pdf)

Food Safety Fact Sheets

More resources will be added at Ohio State's Addressing 2020 Agricultural Challenges website.

Need Business Help? 

OSU South Centers Business Development Network has expert advice, technology, and other resources for small businesses, manufacturers, and cooperatives. 

Learning at home

Ohio State March Ag/NR Madness
Ohio State specialists are offered Agricultural and Natural Resources Madness this March: 64 timely educational events broken into daily brackets (topics). You can register to join these live at 9 a.m., noon, and 3 p.m. each day, or watch recorded events at your leisure. Schedule, registration, and archives can be accessed here: https://agnr.osu.edu/events/agriculture-and-natural-resources-madness.

E-extension Webinars on Organic/Sustainable Production
New and archived organic agriculture webinars are available through e-extension (https://learn.extension.org).

Upcoming seminars include:

The Microbiome: What is it and How Might it Impact Organic Dairy Production?
Monday, March 30 at 2:00 pm EDT

Update on Organic Crop Insurance Options for 2020-2021
Tuesday, March 31 at 2:00 pm EDT

MidAtlantic Women in Agriculture Webinar: Learning From Other's Mistakes: Estate Planning Mistakes and Solutions
Wednesday, April 8 at 12:00 pm EDT

Economics of Grazing Organic Replacement Dairy Heifers
Wednesday, April 22, 2020 at 2:00 pm EDT

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Ohio State hemp trials from 2019

Licenses for hemp cultivation and processing are available in Ohio beginning this week. However, Brad Bergefurd, horticulture specialist at Ohio State’s South Centers, warns potential growers to consider carefully before clearing ground for our state’s budding hemp industry.

“Long term, I think Ohio hemp for seed, fiber and possible nutraceutical products has great economic potential for Ohio agriculture,” says Bergefurd, “but I am afraid early adopters of this crop right now could be setting themselves up for failure if they have not firmly developed their own hemp marketing and production plants well in advance.”

Hemp production has high potential as an organic product, especially for CBD production, which is the type of production Ohio State’s trials focused on. Since CBD is used in health products, manufacturers prefer or require organic practices. But the risk level is high, says Bergefurd. From the university hemp trials in 2019, he found production was very labor-intensive and required specialized equipment for planting, harvesting, and drying. Planting costs alone were around $10,000 - $15,000 per acre. These are risky investments for a crop that might ultimately be confiscated if it fails to meet minimum THC (tetrahydrocannabinol) levels.

Even though the university purchased low-THC  varieties, all the southern Ohio trials failed to pass the legal minimum for THC, says Bergefurd, which is not an uncommon problem. The issue of illegal THC levels, along with falling prices from a national oversupply of CBD hemp, have caused serious losses for farmers in Kentucky and other southern states in the past year, leading to economic strain and farm foreclosures. He doesn’t want to see that happen in Ohio.

In addition to the low THC requirement (0.3% for hemp--compared to average marijuana THC content of 3.5%), hemp crops must be harvested within 15 days of Ohio Department of Agriculture’s THC testing. In the Ohio trials, levels of both THC and CBD rose with decreasing moisture levels, leaving much of a farmer’s fate up to the weather. That’s nothing new; but combined with the other risks and start-up costs, it might give a grower pause.

“We just have a lot of research work to do before we are fully prepared,” says Bergefurd. “Not only for growing the crop, but we have limited to no hemp buyers, or processing and marketing infrastructure developed in Ohio as of today.”

After all, it’s been nearly 80 years since hemp was last grown legally in Ohio. Bergefurd says research is needed to develop management practices for pest control and other production concerns, along with breeding programs to develop varieties better suited to the low THC requirements. He is hopeful that legalizing hemp will be an important first step in creating the research and investment needed to make hemp a viable new market for Ohio.

Ellen Essman, from Ohio State's Law Office urges growers to read through the Ohio Department of Agriculture's Hemp Program page carefully to become familiar with the many rules and fees involved. 

"If you wish to grow or process hemp," she writes in the OSU Farm Office Blog, "there are detailed rules you must follow, such as getting your sites approved, setback requirements, land use restrictions, and providing ODA with information like GPS coordinates of the land and the number of acres and plants you cultivate, just to name a few."

Read more:

"Don’t Hurry Into Hemp” article from OSU South Centers. 

- Ohio Department of Agriculture’s hemp program page.

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OEFFA's 2020 conference is Feb 13-15 in Dayton, Ohio

It's time again for Ohio's largest sustainable food and farm conference. This year's OEFFA Conference will feature a larger trade show area, plus three days of workshop sessions and events featuring more than 70 topics and speakers. 

Among this year's educational sessions, the Ohio State Vegetable Production Systems Lab will host Do's and Don'ts of Getting More From Microbe-Containing Crop Biostimulants on Friday, February 14 from 12:45-1:45pm. Session leader Matt Kleinhenz invites producers to bring along their lunch and share experiences, concerns, and questions about these commonly used, but often difficult to evaluate, products.

Kleinhenz, an Extension specialist and professor with The Ohio State University’s Department of Horticulture and Crop Science, will lead discussion on the promise and challenge of using microbe-containing crop biostimulants in organic crop production, with an emphasis on vegetable production.

While many organic growers use these types of inputs, the benefits of doing so are rarely clear. Kleinhenz will discuss major reasons for these unclear responses. He will also provide tips for selecting, using, and evaluating biostimulant products effectively. The workshop will integrate hands-on demonstrations and how-to discussions, incorporating news from farms, research stations, and product manufacturers. Participant questions and observations will be blended into discussion on product-crop and product-product compatibility, preparation, application, handling, storage, and normal product effects on crops and yields. 

Kleinhenz and his lab have been working with microbe-containing biostimulants for several years, supported by the National Institute of Food and Agriculture USDA Organic Transitions Program and through the North Central Region SARE program. Those unable to attend the OEFFA conference session can read more about Ohio State work with Microbial-based Biostimulants (MBBS) and their Use in Commercial Vegetable Production by visiting the Vegetable Production Systems Laboratory website: https://u.osu.edu/vegprolab/research-areas/vegebiostimsferts/ 

Kleinhenz is one of 17 Ohio State presenters at this year's OEFFA conference. For more details about the OEFFA conference and schedule, visit www.oeffa.org/conference2020.php. Walk-in registration is available for Friday and Saturday's programming. The Exhibit Hall is open to the public on Thursday from 4:00-7:00 p.m. and Friday from 5:00-6:30. p.m. 

Ohio State dairy nutrition researcher Alex Tebbe (left) discusses lab analysis results with on-farm research partner Jeff Miller (right).

Sales of foliar fertilizers have skyrocketed in the last several years, particularly among organic dairy farmers. Foliar products are readily available, easy to store, and many products are approved for organic use and formulated to provide humates, microbiological products, micronutrients, and other popular treatments. Advocates of these products say they offer an environmentally friendly, efficient, and cost-effective way to apply fertilizers. Yet much of the recent research done on foliar feeding has been unable to reliably document benefits to production.

Louceline Fleuridor has spent the last two years studying foliar feeding as part of her Ohio State master’s degree program. She partnered with organic dairy farmers to measure the response of forage and soils to post-cutting foliar fertilization on 19 on-farm sites. As with previous studies in Ohio, Fleuridor found no consistent evidence of benefits from using foliar feeding products.

"In foliar feeding, you apply fertilizer through the leaves, which is contrary to the traditional knowledge that plants will absorb nutrients through their roots,” says Fleuridor, explaining that leaves' primary function is thought to be photosynthesis. "It raises some questions."

On Thursday, December 19, Fleuridor met with participating farmers and Ohio State specialists for a discussion of the research trials and results.

Partnering farmers began the meeting by sharing their experiences with foliar products. Wayne county dairy farmer Jeff Miller began experimenting with foliar feeding on one of his pastures five years ago. He decided to spray half of his pasture to see what would happen and because he couldn’t afford to spray the whole field. But when he noticed how much quicker his herd began to graze in the foliar fed area, he decided he couldn’t afford not to spray the whole field. Other farmers relayed similar experience, noting increases in crop yield, forage health, palatability, and harvested hay quality that coincided with the use of foliar feeding.

Yield gets a lot of attention in studies, but quality and palatability are also important, especially on dairy farms where forage is not the end product. Past studies have noted other advantages to foliar feeds, including decreased nutrient runoff, better absorption efficiency of micro- and macronutrients, reduced instance of disease, and, in a 2000 study on wheat, increased grain protein content.

"Forage quality is where we really expected to see changes, but we didn't," said Ohio State soil fertility specialist Steve Culman, who provided technical assistance on the project.

Fleuridor's study examined a variety of forage quality measurements, including in-field measurements for sugar content (Brix), as well as lab analysis for crude protein, stem:leaf ratio, fiber content, relative forage quality, net energy of lactation, and estimated milk/ton.

In addition to sharing individual and overall test results with the participating farmers, Fleuridor also spent time explaining how researchers use randomized plots and statistics to separate actual treatment differences from differences that happen randomly or from variations in the field. Fleuridor noted that there were some differences between the treatment and control in the studies, but the results were inconsistent and didn’t reveal a cohesive pattern of increased yield, plant health, or milk production for the sites in this study.

Culman cautions farmers to inform themselves before using foliar feeds. “If you’re looking at adding these products, look at the formulation and know what you’re getting. Foliar products tend to supply only a small amount of nutrients.”

Most of the farmers in the study plan to continue using foliar feeding, feeling that these products have caused improvements on their fields. They did note mixed results with some products and a need for additional labor. Several of the participants also stressed that other soil problems need to be fixed before turning attention to foliar feeds.

As for Fleuridor, she feels there are many factors that could have contributed to the mixed results in this study, including weather and soil conditions when the products were applied. She recommended that future studies use a consistent forage composition, and suggested a focus on clover may be advisable, based on farmer feedback.

This study was sponsored by The Ohio State University Paul C. and Edna H. Warner Grants for Sustainable Agriculture, Organic Valley FAFO (Farmers Advocating for Organic), and SoilBiotics. Organic Valley FAFO is currently accepting grant proposals for on-farm research projects. The deadline is February 15, 2020. Read more: https://www.organicvalley.coop/why-organic-valley/power-of-we/farmers-advocating-organics/

Ohio State researcher Louceline Fleuridor applying foliar feed treatments Ohio State researcher Louceline Fleuridor applied foliar feed treatments at spring green up and 10 days after each cutting. Applications were made in the mornings when temperatures were below 75 degrees F.

 

 

 

 

 

 

 

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organic corn

A smaller than usual corn harvest is underway in Ohio. A smaller than needed portion of the harvest continues to be organic. 

According to annual acreage reports from Mercaris, a company specializing in market data and services for organic and non-GMO, the 2019 harvest will see a record number of organic grain acres, despite the notoriously poor spring planting season (1). But the firm also predicted a 12% decrease in actual organic corn yields, compared to 2018, which will lead to increased imports and costs for organic livestock farmers.(2)

For decades, consumer demand for organic food has grown annually by double-digits (3). While still a comparatively small portion of overall agricultural production, organic corn acreage in the U.S. increased by more than 55% between 2011 and 2016, driven mainly by demand from organic dairy farms (4). Despite the large increase in production, organic grain was imported to the U.S. in 2016, indicating the potential for future growth (5, 6). Currently, Ohio ranks in the top 5 states for number of certified organic corn growers, and in the top ten for acres harvested (7). However, relatively little is known about the management practices of these farms.

As part of an interdisciplinary study on soil balancing, Ohio State researchers surveyed certified organic corn growers in Ohio, Michigan, Pennsylvania, and Indiana in the spring of 2018. These four states collectively represent one-third of all U.S. organic corn growers and produce about 20% of the nation’s organic corn.

Corn Growers

54% of organic corn growers were primarily dairy farms, 27% were cash grain operations.

Responses show the majority of organic corn growers in this region are dairy farmers. More than half of the organic corn grown in 2017 was used as on-farm livestock feed. Most (70%) respondents harvested corn as grain corn; 36% harvested corn as silage (with some doing both). Other uses were rare. A surprisingly large number (nearly 2/3) of the growers use horse-powered equipment, indicating they are likely members of Old Order Amish or similar Plain communities.

The survey examined the use of soil amendments, crop rotations, cover crops, various tillage and cultivation strategies, yields, selling costs, and management priorities. Manure and compost were by far the most common practice, used by 89% of all organic corn growers. Other amendments were used by fewer than half the growers. Tillage practices were chosen for weed management, but most other management decisions focused on soil health.

Reported yields varied widely, ranging from 25 to 250 bushels per acre for grain and 5-34 tons per acre for silage. According to the data collected and estimated from survey responses, very few farmers lost money on the fields reported on for this study.

Farmers with more years of experience raising crops organically tended to have higher net returns on average, suggesting that economic performance can be expected to improve over time for transitioning farms. About 40% of respondents had less than five years of experience farming organically.Average yields, prices, and total revenues

Researchers received a 57% response rate (859 responses), yielding a margin of error of 2%.

This work is supported by Organic Agriculture Research & Extension funding grant no. 2014-51300-22331/project accession no. 1003905 from the USDA National Institute of Food and Agriculture. Read more at go.osu.edu/orgcorn.

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Dr. Emilie Regnier with giant ragweed (Photo: OSU/CFAES Ken Chamberlain)

"Formidable."

That’s how Dr. Emilie Regnier describes giant ragweed (Ambrosia trifida). Regnier, an associate professor and researcher in weed ecology, has completed two USDA-funded studies and a survey of certified crop advisors regarding giant ragweed. Capable of reaching a staggering 17 feet tall and responsible for making millions of allergy sufferers miserable, giant ragweed is on the minds of many this time of year. Regnier’s work has shown the ability of giant ragweed to adapt to changes and expand its range both culturally and geographically.

Many of our worst weeds have been introduced from areas where their spread is controlled by natural predators. Giant ragweed, however, is native to North America and has plenty of natural predators, including, at one time, the indigenous people of North American, says Regnier. Just about every part of it is regularly consumed by something. So how is it that giant ragweed remains such a problem?

Most of its advantages center on an uncanny ability to adapt. Giant ragweed shows a great degree of genetic diversity. Anyone can observe this, says Regnier. If you were to collect seed from five different plants and pile them into 5 piles, chances are that the seed from each of those plants would be different in appearance (size, number and size of points, color).

“It’s almost like each plant has a fingerprint,” she says.

This physical variability is something you can see, but it indicates diversity in other characteristics. Former Ohio State graduate student Brian Schutte showed seed dormancy in giant ragweed had wide variation. Most ragweed emerges in early March, but he found some seeds with emergence windows reaching into July and August. This variation makes it easy for giant ragweed to escape weed control methods.

Giant ragweed’s genetic diversity has allowed it to respond and benefit from changes in land use and cropping systems. Initially considered a riparian plant growing along ditches and waterways, giant ragweed is now frequently found in the midst of row crops. Regnier’s survey of certified crop advisors showed that, over the last 30 years, giant ragweed has expanded to fields outside of the corn belt in all directions. It is one of several weeds developing resistance to common herbicides—an issue much in the current spotlight. Ragweed has also benefitted from changes in what Regnier calls the “architecture of modern agriculture,” as soybeans and shorter corn varieties have become more common in rural landscape over the decades.

“The selection for crop species that are shorter, and therefore don’t lodge as much, has lots of benefits; but, on the other hand, it reduces their ability to shade out weeds,” she says, “That might be one of the cultural reasons that giant ragweed has become worse as a weed.”

Don’t despair! Giant ragweed does have some weaknesses, says Regnier. As an annual plant, giant ragweed is completely reliant on seeds to reproduce. Since flowering time is strongly driven by the hours of daylight we know it will begin around mid-August.

“If you can control the plant so that it’s not big enough to flower at that time then you can prevent the reproduction of seeds.”

Giant ragweed typically requires pollen from another plant, so one plant rarely causes an outbreak. And happily, giant ragweed is not a prolific seed-producer, nor a seed that remains viable in the soil for long periods of time. Most giant ragweed seeds lose viability in the first year but can survive longer if buried by deep tillage or stored underground by earthworms and rodents. Even seeds that are produced, are often consumed by mice and voles and sometimes by insects.

What if you already have a giant ragweed problem?

Knowing giant ragweed’s weaknesses can help solve an existing problem.

  • Since most giant ragweed emerges in early spring, having a competitive cover crop or perennial in place in March can reduce its emergence. Alfalfa or mixed hay should be able to control ragweed effectively by providing competition in the spring and with mowing events to set back late emerging weeds. Since the seeds rarely survive longer than one year, including a forage crop in rotation should help prevent ragweed problems.
  • Alternatively, a crop could be be planted later in the spring after most of the ragweed seeds have germinated. The false seed bed technique uses repeated bouts of light tillage to germinate then terminate weed seeds in the field.
  • Taller fast-growing crops densely planted can help shade out later emerging giant ragweed plants.
  • Giant ragweed seeds can float and are often cached by mice and other rodents. Managing the weed in non-crop areas through mowing can help prevent its spread into planted areas.
  • For more on information and resources on organic weed management, visit go.osu.edu/eco-weed-mngt
giant ragweed in flower

Although giant ragweed is less problematic in tall crops like corn, this weed can certainly outgrow field corn varieties, reaching a staggering 17 feet tall.

giant ragweed seeds

Giant ragweed seeds are relatively large (3/16 to 7/16 inch long and 1/8 to 1/4 inch wide) and encased in a woody hull with a distinctive set of points at the top and smaller points or ridges around the middle of the hull. Left on the soil surface, these seeds are a favorite treat of mice and other small rodents. 

young giant ragweed Giant ragweed typically emerges in March. The first (cotyledon) leaves have an indentation at the base and are fairly large -- 3/8 to 5/8 inch wide, 1 to 1 3/4 inches long. The first true leaves are ovate, lobed and directly across the stem from one another. The second pair of true leaves shows the more familiar shape of giant ragweed. Leaves have stiff hairs that point toward the leaf tip and usually form 3 distinct lobes but can have up to 5. 

Photo of young ragweed plants is from the Ohio State weed lab, courtesy of bugwood.org
Other photos by Ken Chamberlain, Ohio State, College of Food Agricultural and Environmental Sciences.

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The organic system in this comparative study benefited beneficial nematodes over harmful ones like this soybean cyst nematode. (Photo: USDA-ARS)

written by Andrea Leiva Soto, Horticulture and Crop Science

Quick Summary
Ohio State researchers compared an organic system to a conventional one, looking at several soil quality indicators such as bulk density, organic matter content, and nematode populations. After four years, the organic system had fewer harmful nematodes, especially during the hay phase of the rotation. Mineral nitrogen was more abundant in the conventional system, while microbial nitrogen prevailed in the organic system. Soil bulk density did not differ between systems, even though intensive tillage was done in the organically managed fields. However, despite the high carbon inputs added to the organic system, organic matter was only slightly higher compared to the conventional system.


Nematodes have a bad reputation for damaging crops and garden plants, but some can be quite important for plant growth. Certain kinds of nematodes eat bacteria and fungi that cause plant diseases. Others decompose organic matter, providing plant nutrients. Studies indicate that nematodes supply 27% of the soil nitrogen that is available to plants. Today, nematodes are increasingly used as an indicator of the status of the soil food web. The soil food web is a complex network with organisms that provide services to the farm ecosystem like regulating pests, nutrient recycling, modifying soil structure, or even breaking down man-made chemicals.

Organic matter additions have been shown to influence nematode populations. Adding green manure cover crops or decomposed animal waste can decrease root-feeding nematodes. Additionally, organic amendments are known to increase soil nitrogen, organic matter and microbial biomass, and reduce soil bulk density, leading to less soil compaction. As a result, roots explore deeper and have more oxygen available leading to more vigorous growth.

However, the intensive tillage practices used to incorporate amendments or control weeds, disrupt the soil ecosystem, affecting the populations of beneficial microbes and nematodes. Synthetic fertilizers, insecticides, and soil compaction can also cause similar undesirable effects.

To better understand these kinds of interactions and develop insights into how best to manage them, a study at the Ohio Agricultural Research and Development Center (OARDC) in Wooster, Ohio, compared conventional and organic farming systems and how soil characteristics, nitrogen cycling, and nematode populations are affected by each system.

The conventional system used chemical fertilizers, herbicides, and reduced tillage in a corn–soybean rotation. The organic system incorporated fresh straw, beef manure, poultry compost, and intensive tillage in a corn–oat–hay rotation. Soil samples were taken in the spring before soil inputs, and in autumn after crop harvest. Samples were taken from between and within the crop rows. Then for each sample, the nematodes were counted and identified, and soil bulk density, organic matter, and nitrogen were measured.

Results: After four years, the organic system had fewer harmful nematodes, especially for the hay phase of the rotation. Mineral nitrogen was more abundant in the conventional system, while microbial nitrogen prevailed in the organic system. Soil bulk density did not differ between systems, even though intensive tillage was done in the organically managed fields. And despite the high carbon inputs added to the organic system, organic matter was only slightly higher compared to the conventional system.

Take Home Messages

  • When you are transitioning to organic, it is important to reduce synthetic inputs gradually. The soil system needs time to build different sources of nutrients to be sustainable in the long-term. It is known that after the transition period, organic farms have more nitrogen in the soil compared to conventional farms, mainly due to a build-up of the microbial nitrogen pool, but these benefits will not be available immediately.
  • Organic amendments and crop rotations can decrease harmful root-feeding nematodes in the soil. And by including hay in the rotation cycle, you can decrease these nematode populations even more.
  • Intensive tillage can reduce the soil-related benefits of organic farming. On the other hand, organic inputs should significantly increase soil organic matter and decrease soil bulk density. In the organic farming system discussed above, the benefits of the large organic inputs were diminished by the intensive tillage routine. Rather than seeing a decrease in compaction level, the soil bulk density remained the same. And there was only a minor boost in soil organic matter. Decreased use of tillage in organic farming would better take advantage of the benefits that an organic system can provide. 

Read more about it:
This study was conducted at Ohio State in the early 2000s. Published results are availabe online.
Briar, Shabeg S.; Grewal, Parwinder S.; Somasekhar, Nethi; Stinner, D.; Miller, Sally A. 2007. Soil nematode community, organic matter, microbial biomass and nitrogen dynamics in field plots transitioning from conventional to organic management. Applied Soil Ecology 37: 256-266.

Read more news and information on organic agriculture research at offer.osu.edu.

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Farmers and researchers exchange ideas at a reverse field day on soil balancing.

The Ohio State Soil Balancing Team is concluding a five-year project examining the beliefs, practices, and effects of soil balancing. Soil balancing involves the use of high calcium amendments to manipulate the ratio of calcium, magnesium, and potassium in the soil. For decades, proponents have claimed that the right balance of these cation nutrients will improve field conditions and yields, but none of these effects have been replicated by modern university research.

Through interviews, surveys, and literature reviews, the team gained a better understanding of why and how soil balancing is used by farmers and how it had been studied by researchers. The group found that while most researchers and university educators viewed soil balancing as an ineffective fertilization program; farmers and consultants who use soil balancing view it as a holistic method for improving soil health.

With input from a farmer advisory committee, the team designed long-term field experiments situated on organic farms and university research sites. The field trials found some evidence that changes in Ca:Mg ratios were associated with changes in soil structure and weed populations. However, the team was unable to document consistent effects on these characteristics, or on soil biology, crop quality, or yield.  

Based on the overall project findings, the Ohio State team recommends further investigation of how soil balancing’s effectiveness is impacted by specific site conditions such as cation exchange capacity (CEC), clay content, or management practices. Meanwhile, the team has issued the following recommendations for anyone using or considering soil balancing. 

Recommendations.

Soil test data is critical to making informed decisions about managing Ca:Mg ratios.

Watch your pH if using lime. Gypsum is a better choice to change your Ca saturation ratio without affecting pH, and it also provides sulfur.

Soils with a CEC below 10 meq/100 g may develop K deficiencies. In soils with a low holding capacity for cations, excess Ca can quickly lead to deficiencies of K, and possibly Mg. We did observe this in on-farm sites.

Consider economic factors. On soils with higher CEC, more time and amendments will be needed to increase the Ca:Mg ratio. Depending on the amount of change needed and the value of your crop, using soil balancing may be cost prohibitive.

Any time you try a new practice, monitor the results. If possible, try using the new practice on only part of your farm and compare it with a similarly managed area to see if the new technique is making a positive contribution over time.

Further Reading.

Additional Resources and Information are available at https://offer.osu.edu/soil-balancing/resource including summary reports, articles, and presentations. 

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