Journal of Nutrient Management - Quarter 3 - 2021

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Published by W.D. Hoard & Sons Co.

August | 2021

Journal of

Nutrient Management

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Application in the off-season Thinking outside the box Composting is an art

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Volume 2 | No. 3

Journal of




Thinking outside the box

Jane Griswold Jenna Zilverberg

4 New neighbors 20 Don’t become a statistic 6 Application in the off-season 22 Composting is an art Look before leaping into Investing in the process 26 8 renewable natural gas 10

Monitoring groundwater at the field level

12 18 When wild weather strikes Dairy rations make milk and manure


DEPARTMENTS First Thoughts . . . . . . . . . . . . 4 Policy Watch . . . . . . . . . . . . . 5 In the Field . . . . . . . . . . . . . . 6 Manure Minute . . . . . . . . . . . 17 On the Move . . . . . . . . . . . . 20 Fresh Paint . . . . . . . . . . . . . 24 Places to Be . . . . . . . . . . . . 25 Nutrient Insights . . . . . . . . . . 26

ON THE COVER Manure from 2,500 cows on this western Ohio dairy is scraped from the alleys and then travels through sand settling lanes. The recycled sand is used as bedding in the freestall barns on the farm that was built in 2000. Manure is stored in an earthen manure storage lagoon, with plans to build a new storage structure providing more capacity in the future. Photo by Todd Garrett, Art Director.

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EDITORIAL OFFICE 28 Milwaukee Ave. West Fort Atkinson, WI 53538 WEBSITE EMAIL PHONE (920) 563-5551

Journal of Nutrient Management (ISSN# 26902516) is published four times annually in February, May, August, and November by W.D. Hoard & Sons Company, 28 Milwaukee Ave. West, Fort Atkinson, Wisconsin 53538 Tel: (920) 563-5551. Email: info@ Website: Postmaster: Send address corrections to: Journal of Nutrient Management, PO Box 801, Fort Atkinson, Wisconsin 53538-0801. Tel: (920) 563-5551. Email: info@ Subscription Rates: Free and controlled circulation to qualified subscribers. For Subscriber Services contact: Journal of Nutrient Management, PO Box 801, Fort Atkinson, Wisconsin 53538, call (920) 563-5551, Copyright © 2021 W.D. Hoard & Sons Company. ALL RIGHTS RESERVED. Content may not be reproduced or used for any commercial activity without express written consent from W. D. Hoard & Sons Company.

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NEW NEIGHBORS A Abby Bauer Managing Editor

day I had hoped was in the much more distant future has arrived. An excavating crew laid the groundwork for a new road that will be built in the field that has been my backyard view for the past seven years. Next will come more houses in our growing subdivision. When we moved into our house, the open field behind our street was one of my favorite features. I grew up in the country on a farm, and even though we chose to live in town rather than find a rural home, I still felt a connection to my agricultural roots each day when I looked out the patio window and saw that field. Every spring, a farmer would come to plant either corn or soybeans. All summer long we’d watch that crop grow until the fall harvest, when the combine would roll by. It was a chance for my young children to see farm machinery working up close — literally in our backyard. I knew this day would likely come, and as the years went by and our little town continued to expand, it seemed almost inevitable. Still, every spring I was so thankful to see the field get planted, knowing it was a sign that development was not happening yet. But, when that first front loader pulled in, I knew change was coming. Our backyard was going to be transformed, and now, someday in the not-so-distant future, new neighbors will move in. This is a reality many farm owners also face. In some situations, a farm may expand into an area where homes were built years ago. More often, though, new houses pop up as farm fields are sold and divided into smaller parcels. Either way, neighbor relations have become more important than ever before. While general consumers tend to be more interested in animal care and the use of genetically modified organisms (GMOs), those living closest to farms are more likely to be affected by and concerned about environmental impacts, including water quality and odor. This is where manure gets its bad reputation. Even though manure is a tremendous source of

nutrients, there is a lot of it — and it has an odor, not typically considered a pleasant one, especially to noses that did not grow up surrounded by agriculture. Like it or not, one goal of a nutrient management system is minimizing the impacts manure has on people in the nearby community. Fortunately, there are solutions available that both utilize manure in productive ways and can reduce odor; some are simple, others are more complex. A few opportunities are covered in this issue, from composting manure to producing renewable natural gas. For Swager Farms featured on page 14, a trial using a zeolite filter reduced both ammonia emissions and odor, something owner Dean Swager considered a win for the environment and the dairy industry. Of course, some manure practices come down to simple courtesy. For example, recommendations for reducing odors when applying manure are highlighted on page 17. Waiting for favorable weather conditions can go a long way in maintaining those neighborly relationships. I am sure many of you learned this lesson years ago. I will undoubtedly miss the extra space and privacy the field behind my house offered, but even more than that, it is sad to see another farm field transitioned away from its agricultural purposes. This is a feeling that has been shared by past and present farmers for decades as urban sprawl pushed into agriculture areas. Yet, farmers will continue to persevere, finding ways to do more with the resources available. As we strive to improve the productivity of livestock and crops, environmental impacts are also top of mind. So, too, should be the impacts of farming practices on people living in the area. For most producers, though, the desire to be a good farmer and a good neighbor is nothing new. Until next time,

Let us know your thoughts. Write Managing Editor Abby Bauer, 28 Milwaukee Ave. West, P.O. Box 801, Fort Atkinson, WI 53538; call: 920-563-5551; or email:

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PENNSYLANIA The Hershey Company, Land O’Lakes, and the Alliance for the Chesapeake Bay have formed a partnership to help improve water quality in the Chesapeake Bay watershed. The goal is to implement onfarm practices that reduce erosion, improve wildlife habitat, reduce water pollution, and minimize greenhouse gas emissions. Initial funding for Sustainable Dairy PA came from the Hershey Company’s $300,000 pledge to help install agricultural conservation practices on 119 Land O’Lakes member-owner farms in central Pennsylvania. These farms ship 50% or more of their milk to The Hershey Company. This partnership has the potential to reach more than 400 Land O’Lakes member farms that supply milk to Hershey as funding and support expands.

WASHINGTON, D.C. A bill concerning agriculture was reintroduced in mid-July after its original introduction in January 2020. The Farm System Reform Act, presented by Senator Cory Booker, D-N.J., and Representative Ro Khanna, D-Calif., places much emphasis on concentrated animal feeding operations (CAFOs). Action items in the proposed bill include: • Placing an immediate moratorium on the construction and expansion of CAFOs • Phasing out CAFOs by 2040 • Providing a voluntary buyout and transition funding for farmers who want to exit CAFO operations • Holding corporate integrators responsible for pollution and other harm caused by CAFOs • Strengthening the Packers and Stockyards Act to ensure fair contracts and treatment of farmers • Restoring mandatory Country of Origin Labeling for beef and pork and expanding it

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to dairy products • Prohibiting the United States Department of Agriculture (USDA) from labeling imported meat as products of the U.S.A. While the proposed bill has the support of animal rights, environmental, and sustainability groups, some organizations within agriculture do not feel the same way. For instance, the National Cattlemen’s Beef Association labeled the act as “misguided.”

MARYLAND The Maryland Department of Agriculture awarded more than $2.9 million in grants from its Animal Waste Technology Fund. These grants are intended to help poultry and dairy farmers improve how they manage manure, protect natural resources, and pursue renewable energy sources. Funding will go toward a poultry litter gasification and dryer facility, manure injection equipment, and an anaerobic digester on a dairy. Funding for the program is provided by the Maryland Energy Administration and the Chesapeake and Atlantic Coastal Bays Trust Fund. To date, the program has awarded $10.7 million in grants to approved projects.

IOWA Researchers at Iowa State University received a grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture to investigate how livestock manure management systems affect the development of antibiotic resistant bacteria. The project will build upon previous research and fill gaps in the scientific understanding of how livestock farming and manure management can reduce antibiotic resistance. They will also assess the feasibility of certain practices, such as composting and anaerobic digestion, in stopping the spread of resistant bacteria.

WASHINGTON A panel of judges determined Washington’s rules for storing and spreading manure are too lenient to protect the state’s water supply and sent them back to the Department of Ecology for revision. The department was already working on a new CAFO permit proposal since the current regulations expire in March 2022 and was expected to release a draft for public review in the near future. It is uncertain how the court’s ruling will affect the timeline for updating the rules. The CAFO permit was issued by the Department of Ecology in 2017. The regulations did not satisfy the dairy industry or the environmental groups, so both sides appealed portions of the permits.

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IN THE FIELD Field day attendees watched equipment made to incorporate fertilizer for off-season application while only disturbing a small amount of soil in each field row. Farming systems, available equipment, location, and other factors will also determine timing of nutrient application. In reality, some fall and spring application will have to occur. Knowing what conditions are important in the fall or spring to prevent nutrient loss is the way to improve nutrient efficiency and protect water resources.

Considerations for fall

APPLICATION IN THE OFF-SEASON When applying nutrients outside of the growing season, certain practices can help minimize losses. by Amber Radatz


utrient applications, from either manure or fertilizer, come with an ever-growing list of items to consider before, during, and after application. Many of these considerations are related to field characteristics or weather and changing seasons. Since 2001, the Discovery Farms programs in Wisconsin and Minnesota have collected and analyzed water quality data from privately owned farms to develop solutions with farmers for the best ways to protect and preserve water quality resources. Discovery Farms is a farmer-led, water quality research and outreach program led by the University of Wisconsin-Madison Division of Extension in Wisconsin and the Minnesota Agricultural Water Resources Center in Minnesota.

There is tremendous power in understanding the conditions that lead to runoff and risk for nutrient loss. Using that knowledge to make small tweaks can pay big dividends toward achieving sustainable levels of nutrient loss.

Depends on the nutrient The best time outside of the growing season to apply nutrients depends on the nutrient of concern. In general, nitrogen is best applied close to when the growing crop will use it. This favors spring application. For phosphorus, spring applications can be a higher risk due to elevated moisture conditions and larger storm events, which correspond to more surface runoff. This favors phosphorus application during the drier conditions of fall.

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Fall can be an excellent time to apply fertilizer or manure. Compared to spring, fall usually has drier conditions and more time for fieldwork. Drier conditions lead to a lower risk of loss via surface runoff. However, without a few extra targeted management steps, fall application can lead to elevated loss of nitrogen. For applications of fertilizer or manure with high levels of nitrogen, waiting for the soil to cool below 50°F reduces the amount of nitrogen that might be converted to the nitrate form. The reason for this slower conversion of nitrogen in the soil is attributed to reduced microbial activity because of cooler soil conditions. Nitrogen in the form of nitrate moves freely with water. It is easily leachable through the soil profile and lost to shallow groundwater or subsurface tile drainage before the intended crop can utilize it. Nitrification inhibitors can provide a week or two of protection in the fall if soil temperatures haven’t dropped below 50°F. Products with known efficacy for inhibiting nitrification are dicyandiamide, nitrapyrin, and pronitradine. These chemical compounds temporarily reduce populations of bacteria in soil that are responsible for converting different forms of nitrogen to nitrate. If nutrient application is earlier in the fall where longer protection is needed for higher soil temperatures, cover crops can be planted to take up some of the applied nitrogen. Spring can also be an excellent time for fertilizer or manure applications. Surface runoff risks are higher, though, because soils are typically wetter and storms are more intense and frequent.

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To reduce risk of nutrient losses in the spring, take a walk through the fields before spreading to assess potential risks to water quality. Note weather conditions and forecasts to assess potential for runoff. Delay applications if conditions for surface runoff are present and the forecast is not favorable. Wisconsin, Minnesota, and several other states have partnered with the National Weather Service and other agencies to create the Runoff Risk Advisory Forecast. This online tool uses Discovery Farms’ runoff data along with weather forecasting technology to assist in predicting when and where runoff might occur.

Follow recommendations Also consider the method of nutrient application. In general, incorporating nutrients into the soil profile is preferable. However, if soil disturbance due to incorporation raises the risk of soil losses on your farm, incorporation would be a disadvantage. Knowing your landscape and runoff risks allows proper assessment of this risk. What follows is an example of where incorporation of nutrients or a change in application timing could have reduced losses. The normal range of nitrate-nitrogen concentration in surface water runoff is 0.05 to 5.2 milligrams per liter (mg/L). When water samples from monitoring stations come back much higher than that range, a nutrient application is sometimes the reason. On one Discovery Farms site, the nitrate concentration of surface water runoff events in May of two different years were over 30 mg/L and ranged up to 80 mg/L. For this field, urea had been broadcast on harvested soybean stubble in late November after the soil temperature had dropped below 50°F. Nutrient management recommendations agree with waiting until soil temperatures have cooled before applying any nitrogen, but it is also recommended that nitrogen applied during this time period be incorporated immediately. As soil

temperatures warmed in the spring, the breakdown of the fall broadcast urea accelerated. Minimal tillage in the spring resulted in the nitrate nitrogen produced from the breakdown of urea remaining close to the soil surface. In this case, water quality data confirms the agronomic recommendations of following all of the associated mitigation steps to reduce nitrogen losses to local surface waters. Before an off-season application, consider the following: • Ensure that crop nutrient needs require this application. • Incorporate nutrients if it doesn’t lead to substantially increasing soil loss. • Wait until soil temperatures are below 50°F for fall applications of nitrogen. • Plant cover crops or utilize nitrification inhibitors. • Assess surface runoff conditions to properly time nutrient applications and reduce risk of loss. ■

The author is co-director of the University of WisconsinMadison Division of Extension Discovery Farms Program.

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Surface runoff nitrate sample concentration (mg/L)

Nitrate concentrations of water samples on one farm 2012 Soybean

2013 Corn

2014 Soybean

2015 Corn

2016 Soybean

2017 Corn


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0 Cropping season Each dot represents the nitrate concentration of water samples by event in six different cropping seasons. The gray area from zero to 5.2 represents the normal range of nitrate concentrations for Discovery Farms’ sites. Elevated concentrations in 2015 and 2017 are attributed to urea applied in the fall that was not incorporated.

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Look before leaping into renewable natural gas As more farms explore renewable natural gas (RNG) options, there are questions that should first be considered. by Abby Bauer, Managing Editor

newer opportunity in the sustainable energy space is the production of renewable natural gas, or RNG, which is created from organic materials such as food waste or animal manure. After manure travels through an anaerobic digester, the biogas produced is then processed into RNG that can be injected into a pipeline for distribution. RNG companies are looking at livestock farms to become partners for production sites. While there is a lot of excitement surrounding these new agreements, it is important that farmers know what they are agreeing to before signing on the dotted line. In the webinar, “How to prepare for conversations with RNG developers,” Newtrient’s chief operating officer, Mark Stoermann, offered some insight and questions to consider before making a long-term commitment. “It’s an exciting time because it’s an opportunity for the dairy industry to have a positive environmental impact but also to diversify the revenue stream,” Stoermann said. However, he pointed out that there is still a lot to learn in terms of putting agreements in writing. “When it comes to contracts, it’s the Wild, Wild West, and that’s really true. Everybody and every project is different,” he shared. “What you need to do,

The biogas produced by an anaerobic digester can be converted into renewable natural gas. as a producer, is really think about your operation and your future as you are getting ready to talk to people about these digester projects.”

Questions to ask yourself Think about things that are very practical. For example, Stoermann said that digesters generally work better if they are not filled with sand. So, if your farm is using sand as a bedding material, you may be asked to switch to manure solids. “Is that something you are willing to do?” he asked. There are digesters that run on sand dairies, but he said they require more water and more revenue to be profitable.

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Another factor he brought up is that there will be more traffic and more people on your property. Are you comfortable with that? Stoermann also said to consider your nutrient management permitting and what you are currently committed to do. Then, envision the future of your operation. “You need to think about the longterm future of the dairy and the project,” he said. He explained that these contracts tend to last 15 to 20 years. If you are not ready to make a commitment for that period of time, you need to talk about it with other people who are part of your dairy. He said to consider the farm’s succession plan, and who will be taking over the operation someday. “What kind of expertise do they have? Will they want to be involved?” he questioned. Additionally, determine if you want the developers to provide all the investment for the project, or if you want to invest in it. “That will probably change the dynamics of how the project looks,” he explained.

Know your costs “Get with your accountant,” was the next advice Stoermann offered. He said you have to know the costs of running your dairy, especially the expenses associated with manure management.

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What are you currently paying for permitting, manure collection, manure transportation, storage, and spreading? How valuable is manure to you as a fertilizer or bedding source? Are you getting any carbon credits? Are you willing to take in other products to get tipping fees? “You really want to look at the whole picture,” he said. These projects require a large capital investment, and while the developer may be footing that bill, they are putting an expensive project next to another expensive project — your dairy. “You want to make sure everyone will be happy with the project and get a fair return,” he said.

Questions to ask the developer Stoermann shared these questions to ask the developer before committing

to a project: 1. How many dairy projects have you developed, and how many are operating? Can I call and talk to your dairy partners? 2. How long do you need to conduct due diligence on this project? 3. What is the expected project term length? “Always make sure you understand the length of any agreement you sign, and be sure there is a termination of each agreement you sign,” he advised. 4. If significant upside occurs in the RNG market, how will you share that with the dairy? On the other hand, if there is significant downturn, what would you expect from the dairy? “Those are good discussions to have before you are committed and sign contracts,” Stoermann said. 5. What kind of termination clause



do you have in the agreements? “It’s always important to have a conversation about termination clauses,” he said. “Everybody has to have a way to have a way out.” 6. Who owns the rights to develop future manure-related revenue? 7. What is your source of capital? Are you open to the dairy participating as an investor? Again, Stoermann reminded that this is a fairly new market, and it pays to do your homework first. “It is the Wild West in some respects,” he reiterated. “You need to do your due diligence to understand what you are getting into.” ■

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Monitoring groundwater at the field level When it comes to groundwater testing results, what you see is what you get . . . or is it? by Michael Sklash and Fatemeh Vakili


hen a red light starts to flash on your vehicle’s dashboard, it usually means something is wrong with your vehicle . . . but not always. It could be a faulty sensor. The same is true for monitoring nitrate in groundwater at the local field level. The nitrate concentrations in groundwater from a monitoring well may not be representative of the current farming practices on the property. Recently, we have been asked to comment on monitoring data for nitrate in groundwater collected from a single monitoring well. We will share two examples that reflect the difficulties with interpreting this type of data.

Results from a single site The first example started as a hypothetical: What do the nitrate concentration data from a single monitoring well in a field fertilized in part using manure from a larger dairy indicate? Our response began with the “brainstorming” sketch shown in Figure 1. The monitoring well provides groundwater data from just below the water table, about 50 feet below ground level. The soil is all sandy and extends from ground surface to at least 90 feet below ground level. What do we need to consider with respect to the origin of the nitrate in the groundwater versus current agricultural practice? Does “legacy nitrate” contribute

Precipitation varies from year to year Low area focuses recharge Travel time from ground surface to water table Water table at about 50 feet Legacy nitrate concentration may vary with depth Regional groundwater flow with legacy nitrate

Irrigation well with drawdown cone Sandy soil extends to about 90 feet below ground

Figure 1: This is the recreation of a brainstorming sketch of the factors that can affect nitrate concentrations in groundwater at a single monitoring well. to the groundwater under the field? Legacy nitrate is nitrate in the groundwater that originated from past agricultural practices somewhere upgradient from the single monitoring well. In a previous article (“Tracking down the nitrate source,” February 2020), we discussed how we can use “isotopes” in the nitrate ion to differentiate between a manure source and a chemical fertilizer source for the nitrate and isotopes in water molecules to estimate groundwater age. The concentration and origin (manure or chemical) of the legacy nitrate can vary with depth below the water table. Which part(s) of the nitrate does the monitoring well sample?

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Single monitoring well on field

How long does it take for nitrate to reach the water table under the field? This, in part, depends on how much precipitation occurs, which can vary from year to year. It also depends on the soil (types and spatial distribution) and the depth to the water table. In our hypothetical example, it takes many years for the precipitation and nitrate from the current year to reach the water table. If farming practices change, when do the effects of the current farming practices show up in the water table? Low areas in the field can focus recharge from precipitation and irrigation. How does this affect nitrate movement to the water table? Does the

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location of the single monitoring well result in groundwater nitrate data that are representative of the entire field? If groundwater is used for irrigation, it can bring legacy nitrate to the surface. Irrigation wells can also homogenize the legacy nitrate in the groundwater to further complicate the issue. Does this affect the nitrate distribution in the groundwater?

The agricultural impacts So, what does nitrate concentration data from one groundwater monitoring well tell us about the impacts of current agricultural practices? Thomas Harter from the University of California, Davis presented a webinar last fall where he discussed the areal variation in nitrate concentration in groundwater near the water table in a commercial almond grove in California’s Central Valley. The study site was a mile square, intensively instrumented (including 21 monitoring wells in a grid), and had detailed geological information. Here is what was stunning about this study: Where the area was uniformly farmed, the areal variation in nitrate concentrations in groundwater included a difference of about 80 mg/L between two adjacent monitoring wells about 800 feet apart. Harter’s study site had significant spatial variation in subsurface soil types. The second example is similar to the hypothetical site. The second problem involved the “background” monitoring well at an existing dairy. The site is underlain by sandy soil with the water table at about 20 feet below ground level. The regional groundwater has high concentrations of legacy nitrate, up to about 80 mg/L in some places. The legacy nitrate originated from decades of chemical fertilizer use and heavy irrigation for crops. The dairy’s problem was that the nitrate concentration in groundwater at the “background” monitoring well was consistently less than 10 mg/L; that is, it was not representative of the (legacy) groundwater moving onto the dairy property. How could this happen? We took two actions to find out. First, we installed data loggers in the “background” monitoring well and several other wells to record the elevation of the water table continuously for a period of months. This allowed us to determine

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A flooded vegetative treatment area and the “background” monitoring well. the groundwater flow direction at the “background” well continuously. With this information, we could determine whether the regional groundwater, with its legacy nitrate load, was always flowing onto the dairy property or not. Second, we conducted a large scale, natural tracer test next to the “background” monitoring well to determine where the groundwater originated. A large, spring rainstorm caused ponding of the vegetative treatment area (VTA), which is used to treat part of the nonproduction area storm runoff. The photos show the flooded VTA and the “background” monitoring well. Three main things happened. First, the data loggers indicated that the water table “mounded” from infiltration of the ponded water in the VTA, compared to areas further from the VTA. The mounding reversed the direction of groundwater flow at the “background” monitoring well; that is, the groundwater with the legacy nitrate episodically stopped moving onto the dairy property. Second, the ponded water, which was virtually free of nitrate, diluted the nitrate concentration in the groundwater at the “background” well as it seeped into the ground and caused the mounding. This did not occur at monitoring wells further from the VTA. Third, we were able to test the ponded water and the groundwater around the dairy for oxygen and hydrogen isotopes

in the water molecules (see our February 2020 article). The ponded water and groundwater were very different isotopically, but the groundwater at the “background” monitoring well became like the ponded water isotopically. In other words, when it rained heavily, nonproduction area runoff ponded in the VTA, creating preferential recharge to the groundwater. This caused localized groundwater mounding, blocking of the regional groundwater inflow with its legacy nitrate, and nitrate dilution in the groundwater around the “background” monitoring well. Two other interesting observations were made. We installed monitoring wells further upgradient than the “background well,” beyond the mounding effect. Data from these upgradient monitoring wells confirmed that the regional groundwater with its legacy nitrate was still flowing toward the dairy (see the first consideration in the first example). The downgradient monitoring wells at the dairy also had nitrate concentrations considerably lower than the legacy nitrate concentrations. It is possible that because the VTA is located in a naturally lower spot, this area has always acted as a preferential recharge area, long before the dairy was built (see the fourth consideration).

Ask more questions Do you need to be alarmed by the “flashing light” of the high nitrate concentrations in groundwater observed at a single monitoring well? We suggest that you and the regulators exercise caution when using nitrate concentration data from single monitoring wells to make decisions about your farming practices. Do the data make sense in the big picture? Are there special circumstances that may skew the nitrate data? Do you need to step back and look at a larger area to help interpret the local nitrate data? Can isotopes and high-resolution water level data help to explain what is going on with nitrate in the groundwater? Ask yourself these questions first. ■

The authors are a senior hydrogeologist and a hydrogeologist, respectively, for Dragun Corporation.

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Dairy rations make milk and manure While a ration is formulated to optimize milk output, we shouldn’t ignore the nutrients excreted in the process. by Steve Martin


hen considering the task of formulating rations, I think about building blocks. When an architect and a contractor work together to build a house, there is a plan and there are materials. Building dairy rations is much the same. Instead of wood, steel, and concrete, we create dairy rations with ingredients like corn, soybean meal, various by-products, and forages. In reality, though, the nutrition formulation model I use looks deeper. It is not concerned with the use of soybean meal or canola meal, or corn silage or alfalfa hay. It is, however, very interested in carbon and nitrogen as well as various vitamins and minerals. This is science that has been in development for more than 100 years and is getting more complicated by the day!

Nothing goes to waste The reason I refer to the building blocks concept is that dairy producers buy these nutrients through feed purchases and crop or forage farming costs. Then they sell these same building blocks, repackaged by the cow in the form of butter, cheese, fluid milk, and beef. The most amazing part is how the microbial action in the cow’s rumen converts items inedible by humans, like wheat straw, corn stalks, and

Rations that are formulated more precisely save money and reduce unused nutrients being released through manure. ethanol by-products, into nutritious human foods. Cows are the ultimate “up-cyclers.” However, the process is not perfect, nor 100% efficient. For every cheeseburger and milkshake value meal at a fast-food restaurant, there is manure that is also created. We won’t, however, call it waste since the cattle industry is excellent in using this co-product

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for either methane digesters or crop production fertilizer. Nothing goes to waste! Even the solids left over after creating methane can be an excellent, clean bedding option for the cows. The newest technology is even creating perfectly clean water from the “other” product produced by our cows. Though most of these manure management ideas and plans come from our

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engineering friends, the formulating nutritionist has a hand in the beginnings of the process. How much, though, can my efforts to build rations impact the problems or opportunities of the manure-based products?

Thinking beyond milk In the dairy world, I think the nutritionist’s role is a bit different than it is for other livestock species. I won’t say it’s harder, but it is different. The beef or swine nutritionists don’t have the opportunity to have their ration adjustments judged by tomorrow’s production measures. In dairy, it is usually no secret if a ration is deemed a good one or a failure, and the decision could come as soon as a day or two from it being fed. As we think about so many numbers, including milk to feed economics, cow health and reproduction, forage and grain inventory management, and how much protein and fat is in the milk, is there really room left at the table to think about more things? Do the nutrient management implications of the feeds we formulate — those that are not converted into milk or beef but end up in the manure and the urine — have a role? I grew into my role as a dairy nutritionist in Stephenville, Texas, in the early 1990s. Among other regions of the country that found themselves at odds with regulators, politicians, and the media, the Central Texas dairy industry had an issue with the city of Waco. I am sure the details can be found online, and the struggles were not unlike those elsewhere, but the impact of this issue for me as a young nutritionist was to not add any supplemental phosphorus (P) to our rations. I remember being told by a client that he was more worried about Waco than he was the question of how the level of P compared to the established requirements for what a cow needed in a diet. “We can’t take the risk” was the directive. At about the same time that this supplemental P reduction was in motion in Texas, we started feeding more and more by-product ingredients that were actually higher in P than primary grains like corn or traditional forages. The fact that P is not a cheap addition to a ration was helpful since removing routine supplemental levels actually was a feed cost reduction for the dairy. A win-win, it would seem, except for the politics that overwhelmed the situation. The question about whether it was a human source or a cow source of problematic P in the river was complicated by the various area sewer treatment plants in the same area as the dairy farms. I am not sure how the politics and the science sorted itself out in that situation, but the result for me is that I still rarely include supplemental P in dairy rations.

to be sure there is enough for the cow. A dairy nutritionist is quickly judged by their client based on milk production and cow health. At times, the least-risk position for the nutritionist was to be sure there is enough of everything by adding a little extra of many things. With our current intricate nutrition models and complicated on-farm feeding systems, we now have the ability to feed cows building blocks in a more thoughtful manner. One of the ways to accomplish this is through more laboratory analysis of feedstuffs to be sure we know what we have and only add supplemental levels of nutrients to meet and not exceed guidelines. Feeding groups of dairy cows by their stage of lactation is another way to not only manage feed costs for the producer but also limit unused nutrients that end up in livestock manure and urine. Taking care to consider all of these implications when building diets is the job of a competent and forward thinking nutritionist. ■

The author is the founder of DNMCmilk, which works with dairy producers and heifer growers in several regions of the U.S. and around the world.

The extras add up Phosphorus is only one example of nutrients that can be included into diets at excessive levels and either not help or even potentially hurt cows. It may be excessive protein levels in rations that result in a nitrogen loss into the environment or various trace minerals that are fed at a routine excess just

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August 2021 | Journal of Nutrient Management | 13

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The centrifuge at Swager Farms runs at 250 gallons per minute. The water removed from manure enters the centrifuge to be polished, sorting out the smaller particles missed by the screens.


This Idaho dairy mixes simple concepts and mechanical systems to best handle manure.

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by Abby Bauer, Managing Editor


airy farmer Dean Swager isn’t one to just maintain the status quo. “If we can do something better, God gave us an opportunity to learn more and be better in our lives,” he said. He has applied this philosophy to many aspects of his dairy located in southern Idaho. For instance, to more accurately measure feed ingredients for each load of total mixed ration (TMR), Swager created a system using a conveyor belt, a scale, and a trap door that only allows the exact pounds of forage needed into the mixer. Recognizing the important role water plays in ruminant digestion, Swager also installed a free-flowing water system that runs along the feedbunks. With more water accessibility, “All cows have an equal opportunity to drink water all day,” Swager said, and he found that cows actually eat less feed and produce more milk now. “Anything to bring efficiency up in a cow is a win-win,” he commented. He applies this “outside the box” thinking to manure management as well. He shared some of the changes he has made to the farm’s manure handling systems and processes in a virtual farm tour during the Pacific and Mountain West Nutrient Cycling, Soil Health, and Food Safety Conference.

cow lanes, while the solids are composted in windrows and then used for bedding in the freestsall barns. He said the amount of reclaimed solids has doubled since they installed the centrifuge. Swager said that the system requires little maintenance. The screens are pressure washed once a week and are treated with acid when necessary. The centrifuge is shut down once a week to be greased, but that is about it for regular maintenance. A bonus of installing the centrifuge has been fewer solids in the manure lagoons. “I hardly ever need to clean my lagoons,” Swager said. “Before, it was a full-time job, cleaning at least one lagoon every year. Now, that’s not necessary with a centrifuge. You could see tire tracks at the bottom of the lagoon from cleaning the year before.” When asked if he was satisfied with his installation, Swager said, “Absolutely. I think every dairy farm could utilize a centrifuge in some way or another.”

Out to the field To empty the storage lagoons and move manure to the fields, Swager was looking for a different method than haul-

Down the lane Swager grew up on a dairy farm in southern California that was established by his father in 1945. The family moved their dairy to Buhl, Idaho, in 2000, and over time it has grown to their current size of 4,800 milking cows and 1,000 crop acres. Today, the herd of Holsteins averages around 85 pounds of milk per cow per day. The operation was set up as a flush dairy, which utilizes water to clean the alleyways. “Nutrient management has always been a big focus of mine because of the flush system,” Swager said. “It was a problem that needed to be solved sooner rather than later.” He said they have tried a “plethora” of manure handling methods over the years. His takeaway has been that in most instances, simpler is better. “Gravity works every day,” he shared. “It has worked since the beginning of time. You don’t need anything but gravity to take out most of the solids.” Manure is flushed from the freestall barn alleys down into a receiving pit. A pump moves the manure over some coarse screens for initial solids removal. Then, the manure flows down to another pit, where it is pumped into a third pit that feeds a centrifuge. To remove the smaller particles, Swager installed the centrifuge 4-1/2 years ago. Running at 250 gallons per minute, the centrifuge polishes the water, taking out the solids that the coarse screens miss. Swager explained that when the solids are spun, they stick to the outside of the barrel, just like wet clothes in a washing machine. The solids travel up an incline inside the centrifuge, getting drier as they move along, eventually leaving the centrifuge dry enough to make a cone pile. The water removed by the centrifuge is reused to flush the

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As part of the farm’s nutrient management system, screens remove the solids from manure. These solids are composted in windrows and are then used for bedding in the freestalls.

farms need to do. But for today, this is a great way to mitigate problems.”

Better air for all

ing with trucks like he used to do. “I needed a better way to not go into the lagoon and disturb the bottom with heavy equipment,” he explained. “Also, I needed a way to remove slurry without taking a year worth of drying, even in ideal conditions, to get that slurry dry enough so it could be hauled out.” About six years ago, Swager settled on a drag hose system for a simple reason. “It’s a tried and true technology that’s been used for many years, more in Eastern states than here, but if it works there, why wouldn’t it work here?” he shared. Plus, he was able to utilize drag hoses with the system he already had in place. “We just put the pump in and start pumping. There’s no prep involved,” he explained. “And no one is covered in cow manure at the end of the day.” Another benefit is that the manure is applied more precisely. “It puts the nutrients where you need the nutrients. They are not on the surface; it puts them down below, where it’s plant available,” he explained. On a good day, he said they are running 1,000 gallons of manure per minute through the injectors, “so we can put a lot of product down in a short amount of time,” he noted. The draglines are only used for about a month out of the year. He said

maintenance includes the basics, such as diesel fuel, oil changes, and filters. As for the drag hoses themselves, he said they usually last about three years before needing to be replaced. When comparing the cost of the current drag hose system to his former method using tankers and hiring someone to pump out the lagoon, he said he was able to pay off the drag hose system investment in a year and a half to two years.

As for the crops, “Our yields are so much better now. The crops are so much better now,” Swager shared. “They are not affected by spreader trucks driving over the fields and creating compaction.” He also reiterated the benefit of putting the nutrients down in the soil. “It’s just a way better system for putting nutrients on,” he said. Looking forward, Swager said, “Ultimately, we need to keep the nutrients out of the lagoon. That’s what dairy

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Swager also worked with the University of Idaho to install a trial zeolite filter on his dairy. Zeolites are minerals of volcanic origin, and one of the most abundant and commercially available zeolites, clinoptilolite, is mined in Idaho. A filter made using this zeolite has the potential to reduce ammonia and other emissions from stored manure. When approached with the idea, Swager was willing to give it a try. “Systems that can reduce ammonia emissions on the farm would be a great plus to the industry,” he said. His early opinion about the filter was encouraging. He noticed a drastic reduction in ammonia emissions. “The zeolite filters are a low-cost option to solving a bigger problem,” he said, noting both reduced emissions and less odor. “I am all about anything positive the dairy industry can do for the environment.” Swager finds partnerships with the state’s university to be valuable, and he appreciates the work they do. “The University of Idaho does excellent research, and they are always looking for the next step,” he said. “If we simply do the same thing over and over, we can’t expect different results.” Swager considers himself to have a “why and how come” type of mind. “I like to test why things work the way they do,” he said. His advice to other farmers was to adopt a similar mentality. “We don’t just have to do things like Dad did because it worked for him,” Swager said. “Ask yourself, ‘Can we do it better?’” Swager doesn’t have a specific plan yet as to what is next for manure management on the dairy, but his eyes and ears are wide open for new ideas that could improve his farm and the world around it. ■

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and application of manure is a common source of neighbor complaints. University of Nebraska’s Rick Koelsch shared tips for minimizing manure odors in an Extension Dairy Bulletin. Koelsch said that incorporation of manure is the best practice for controlling odors after application, as soil is an excellent filter to remove the smell released by manure. However, for various reasons, manure incorporation is not always feasible. If not incorporated, he said the 36-hour period after land application is the most critical, as this is when odors will be most noticeable. When determining which fields

to apply manure to, Koelsch said wind direction is the most important piece of information one can gather. Odor plumes will travel in the same direction as the wind. The edges of the field that are perpendicular to the wind direction will likely be most impacted by any odors. Watching the directional wind forecast for a 36-hour period after application allows farmers and applicators to select fields, when possible, that will least affect neighbors. Night time hours, with cooling temperatures and light winds, are when people are more likely to be exposed to the smell of applied manure. That’s because the odor plume is not diluted

and atomspheric conditions hold it close to the ground. During the day, Koelsch said odor plumes generally rise and are diluted with fresh air. Additionally, sunshine, wind, and warm air help to disperse odors. Koelsch emphasized that weather forecasts providing wind direction and speed, sky conditions, and temperature are very valuable when determining when and where to apply manure. If a person is not able to wait for more desirable weather conditions, Koelsch said to focus on the nighttime wind direction and use this information to select an application site with the fewest downwind residences to minimize neighborhood exposure.


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Uncovered manure storages should be built with freeboard, which is extra area at the top of the structure reserved for emergency situations, such as extreme weather conditions that prevent manure from being emptied and applied.

When wild weather strikes Prepare for weather’s effect on your farm’s manure management strategy. by Sarah Fronczak s we experience more variable weather, like frequent and stronger storms, it has become more crucial that livestock producers check and monitor the integrity of earthen or concrete storage structures and manure transfer equipment. Wear and tear, as well as

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winter weather, can take its toll on the equipment depended upon to move manure from collection points to long-term storage structures. Spills may be caused by burst or ruptured piping, leaking joints, or failures of the storage. Monitor the condition of manure storage structures as well as all manure transfer pipes,

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pumps, and valves to ensure they are performing as expected. Develop a regular schedule to inspect each component of manure storage and pumping equipment. Create a checklist of items to be inspected, including dates and times of inspection, to ensure a thorough, timely, and regular process. Farm size and complexity of the manure storage system, mechanical devices, distance to surface water and wells, type of storage structure, and occurrence of rainfall or snowmelt should all be considered when determining inspection frequency. Regular checks and maintenance of all pumps, agitators, piping, valves, and other mechanical and electrical equipment will confirm everything is in good operating condition and minimize the risk of any spills or leaks.

Check the structure For all storage structures, especially earthen, cautiously walk the perimeter of the storage based on your rainfall amounts, weather forecasts, and storage situation. Recognize that berms for earthen storages, just like fields, may be water saturated and weakened. Assess how solid the sides are, looking for low points or areas with lower structural integrity. Roots from invasive plants and animal damage can contribute to manure storage weakness. The extreme cold may necessitate checking more often due to the depth of frost in the ground that puts external stress on a pipe.

Plan for emergencies Each farm location has unique risks for manure to reach surface waters. Assess your risk, consider what the worst-case scenario might be, and think through a plan to address that situation before it occurs. Identifying what is in the down slope direction from the storage will help you think through what sensitive areas are along that path and how critical the risks could be. Know how to get earth moving equipment on site as soon as possible and plan where potential

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berms would need to be built to divert the flow from reaching surface water, neighboring properties, or roadways. Even when there are not imminent risks to surface waters, have plans in place to contain, control, and stop manure from moving overland. If your farm doesn’t have a written plan, you can learn how by reading the Michigan State University (MSU) Extension bulletin E-2575s, “Emergency planning for the farm: Livestock operations.”

Keep clean water clean A manure storage structure that captures excess clean water runoff from around the farmstead, in addition to direct rainfall, obviously fills up even faster. Diverting clean water from reaching the lagoon would help maintain needed storage space. Gutters and downspouts on all the buildings, especially ones near livestock lots, can divert clean water away from manure and other contaminants. It also helps with relieving pressure on the manure storage freeboard situation. Roof runoff is a cost sharable practice through the Environmental Quality Incentives Program (EQIP). Contact your local Natural Resources Conservation Service (NRCS) office for more information. Be sure to exclude livestock from rivers and streams. Fencing and flash grazing are also important practices to keep surface water clean. Maintained buffers around surface water and sacrifice lots are valuable tools, as they can capture any contaminated lot or roof runoff before it reaches clean surface water.

Maintain extra space Rain has a way of making spring fieldwork difficult, slowing the progress of all fieldwork — including emptying in-ground manure storages. Freeboard is the top area of a storage structure that is reserved for emergencies. The more rain that falls, the more freeboard space disappears in the storage, and there is less opportunity to spread manure without getting stuck.

What can you do? If your manure storage is looking dangerously full, there are some actions you can take to relieve the situation and the impending environmental emergency. There are no simple solutions, but thinking through your specific situation and monitoring it daily can help prevent, or at least minimize, environmental risks and potential regulatory issues. For starters, design outside manure storages with freeboard to deal with extreme spring weather. Freeboard is typically 12 inches (6 inches for fabricated structures), plus the additional storage volume necessary to contain the precipitation and runoff from a 25-year, 24-hour storm event for your region. Do everything you can to reduce liquid manure storage before it is alarmingly close to overflowing. Even relieving a few inches off the top will buy some time and reduce stress on the storage system. If you find yourself getting close to freeboard, you can haul to your driest field or a field with a growing perennial crop growing like alfalfa or grass, keeping in mind crop damage may occur. There is a significant possibility you will damage your hay stand, and any time you are on wet fields, compaction will occur. You could also transfer some manure to a different storage system, whether that be on your farm or that of a family member or neighbor. If you can’t haul to your own fields or transfer to a different storage system, see if you can haul to a neighbors’ field(s). Review the neighbor’s nutrient management plan with them and follow it. In the event that a manure storage breaches and manure reaches surface waters, contact your region’s pollution hotline immediately. Reacting promptly can help minimize the impacts in a negative situation. ■ The author is an environmental management educator with Michigan State University Extension.

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DON’T BECOME A STATISTIC Manure hauling and application equipment has some dangerous features that must be acknowledged. by Abby Bauer, Managing Editor


ike many employed in an agriculture career, custom manure applicators find themselves working long hours and in stressful situations. When the pressure is on, it is easy to want to cut corners to get the job done, but these shortcuts can sometimes mean the difference between life and death. A vital component of any manure applicator training or certification program is a focus on safety. As part of the Minnesota Department of Agriculture’s Commercial Animal Waste Technician applicator training, Rick Martens, executive director of the Minnesota Custom Applicators Association, covered this critical topic. “Keep safety in mind at all times,”

said Martens, who also owns and operates a custom application business. “Each type of equipment has special features that require special attention.” He started out by discussing pinch points and moving parts. For instance, liquid applicators may have wings that fold up for safe transportation, and solid manure spreaders can have moving end gates and rotating beaters. “There are many ways that fingers or other body parts can be pinched and crushed, or clothing may be caught,” he noted. “Don’t put your fingers where they don’t belong.” During maintenance, Martens said to always turn off the equipment and block it securely to avoid being crushed. A device that has caused many tragic

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accidents is the power take-off, or PTO. Found on many manure hauling implements, this is an area where Martens said to stay alert and use extreme caution. Injuries that can be caused by PTOs include fractures, lacerations, spinal cord damage, amputations, and sometimes death. To illustrate the sheer power of a PTO, Martens shared that a PTO shaft with a 3-inch diameter spinning at 540 rotations per minute (rpm) travels 7 feet in just one second. At 1,000 rpm, it travels 13.1 feet per second. A safety feature of a PTO is the protective shield, and Martens said to keep the shield in place and in good working order. “Shields that become damaged should be replaced,” he advised. “A

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replacement shield costs $100, which is a bargain compared to any accident you may face when working with a broken or missing shield.” He said to never step over a PTO shaft that is not covered by a shield. “It’s not worth the risk to step over a PTO shaft . . . ever. Walk around the equipment,” he emphasized. When working with PTOs, Martens said to focus on what you are doing. Don’t wear loose clothing or clothes with ragged edges, and remove strings, such as those on hooded sweatshirts. Stand away from the shaft and look for others, especially children and animals, before turning on the machinery. Again, he said to turn off all equipment before performing maintenance. Hydraulic oil and hoses create another potential safety hazard. “The main concern with hydraulic hoses is that they can be very hot, and the oil running through them is very hot,” Martens explained. In addition, the oil in the hoses is under high pressure. Even a small leak the size of a pinhole can cause dangerous fluid to spray out with such force it can cut the skin, and it can also cause chemical burns. This is a huge risk to hands, eyes, and skin, Martens shared. If a hole in a hose is suspected, Martens said to never use your hands to feel for the leak. This may result in hydraulic oil being injected into your body.

Working around the clock Martens recognized the challenges manure applicators face. “Today, our equipment is getting faster, application styles are changing, and we need to keep pace with that,” he said. “The pressure is on for us to get more done in a shorter amount of time.” This time crunch raises the risk for accidents and injury, but he also reminded that accidents can happen even when working under favorable conditions. “People are people. We make mistakes. We forget things. We do things in the wrong order. We do things we shouldn’t do. We get distracted. We get overloaded,” he said. He emphasized that safety is an

F2 20-21 Aug 2021 On the Move.indd 3

ongoing effort. In addition to regular safety training and routine maintenance of equipment, he encouraged applicators to wear the proper gear. This includes good boots, gloves, long pants and sleeves, safety glasses, and

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Composting is an art Temperature, moisture, and particle size make a difference when composting used bedding and manure. By Abby Bauer, Managing Editor

Building the pile The size of the compost pile depends on the scale and needs of the operation. Modderman said a farm could have one large compost pile or several small ones at different decomposition stages. At a minimum, a pile should be 3 feet

Abby Bauer


anure composting uses microbes that already exist in manure to break down organic matter such as manure and bedding, and it requires certain conditions to be successful. According to Chryseis Modderman with University of Minnesota Extension, wellmanaged compost may take four to six months to reach completion, but with diligent aeration and management of the pile, it can reach completion in as little as two months. The key is that a compost pile must be actively managed. “To be successful with composting, it takes more than simply piling manure and waiting for it to break down,” said Modderman during a University of Minnesota Extension composting workshop. She explained that basically everything done in compost management is to keep the microbes happy, as they are the ones breaking down the materials. Both acceptable and preferred ranges for several characteristics of a compost pile can be found in the table. “Proper composting is almost an art, and it takes the right combination of particle size, temperature, moisture content, oxygen, and carbon-to-nitrogen ratio,” Modderman said.

A pile of manure and used bedding goes through three temperature phases as it composts. by 3 feet and 3 feet deep. “Anything smaller than that won’t be able to generate the internal heat necessary,” she explained. If you plan to compost during the winter in cold climates, piles should be at least 5 feet by 5 feet and 5 feet deep. The maximum size should not exceed what your machinery can effectively turn and mix. When building a compost pile, Modderman said you want a smaller particle size, which gives more overall surface area. This means the microbes have better access to degrade these pieces. If particles are too small, however, they will fit together too closely and limit oxygen in the pile that the microbes depend on. Particles from an eighth of an inch to 2 inches long are

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best. Manure is crumbly and can be broken down, but coarse bedding such as corn stalks might need to be shredded

The phases In the life cycle of composting, there are three temperature phases. The first is the warm up phase, which Modderman said lasts a few days to a month. This takes place from when the pile is formed to when the internal temperature reaches 105°F. Next is hot composting, or the thermophilic phase. “This is where real work is done by microbes,” Modderman shared. It can last four to six months. Maintaining the pile between 110°F and 150°F is crucial since the microbes are most productive in this range. “If the

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pile falls below this temperature range, microbes will become dormant and slow down or completely stop,” she said. On the flip side, if the pile reaches a temperature over 160°F, microbes will also die off and decomposition will slow down or stop. Turning the pile will lower the overall temperature and keep the composting process going. Once the temperature no longer rises, that is a good sign the second phase is over. The third phase is the cool curing stage, which can last up to four months. This phase begins when the compost pile returns to lower temperatures, usually below 105°F. At this point, further decomposition by fungi, worms, and other organisms takes place. Modderman said this step can be skipped and that the compost can be used as a nutrient source directly after hot composting. However, compost that is allowed to cure will be more stable and a more complete product. Throughout all stages, heat should be monitored with a thermometer probe. The amount of heat in a pile is a good indicator of how the compost is progressing, she said, and temperatures that seem off are usually a sign that something isn’t right.

The right moisture Another key area is moisture level. “Moisture in compost is crucial for the reactions to break down organic materials,” Modderman said. “It also helps regulate temperature.” The optimal level is 50% to 60%

Characteristics of a well-managed compost pile Characteristic

Acceptable range

Preferred range

Particle size

1/16 to 4 inches

1/8 to 2 inches


105°F to 160°F

110°F to 150°F

40% to 65%

50% to 60%


5% to 20%

10% to 15%

Carbon-to-nitrogen ratio

20:1 or 40:1

25:1 to 30:1


Source: On-farm Composting Handbook NRAES-54

moisture, but many microbes will still do their job at 40% to 50% moisture. If moisture content is too high, the pore space in the pile will fill up with water, which will limit the oxygen supply. Modderman said compost breakdown is also hindered if moisture is too low, as the microbes need a moist environment. Composting can occur with as little as 25% moisture, but it will be very slow, and the destruction of weed seeds will be hampered below 35% moisture. There is a simple way to check if composting manure is in the correct moisture range. While wearing gloves, Modderman said to conduct a “squeeze test” in several areas of the pile. If water drips from compost squeezed in your hand, the compost is too wet. If you open your hand and the compost falls apart, it is too dry. Compost with optimal moisture should hold its shape and feel like a damp, but not wet, washcloth. If moisture is not in optimum range, there are a few ways to alter it. Covering a compost pile, with a permanent roof or a tarp, gives control of moisture level. Additional aeration and turning

can help if a pile is too wet. On the other hand, if compost is too dry, it can be moistened with water. Compost piles also need the right amount of oxygen, and the need is greatest early on. According to Modderman, a minimum of 5% oxygen in the pile is necessary. Oxygen is most abundant in the outer layers of a pile, and turning and mixing the compost is important to spread oxygen throughout the pile. Another important component is the carbon-to-nitrogen level, and one can send a sample into a laboratory to determine the ratio. “It’s valuable to know what components are out of balance so you know how to fix them,” Modderman said. To remedy a low carbon-to-nitrogen value, one can add carbon sources such as straw or wood chips. To fix a high carbon to nitrogen ratio, add nitrogen sources, such as grass clippings or hay. Modderman reminded the audience that aged manure is not the same as composted manure. Following the guidelines in this article will assure composting has effectively taken place. ■



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209 N. 4th Ave. St. Nazianz, WI 54232


Tomorrow Water

1225 N. Patt St. Anaheim, CA 92801 714-578-0676 1-800-799-3740

COATINGS 5115 S. Rolling Green Ave. Ste. 211 Sioux Falls, SD 57108 605-254-6059

Due to the COVID-19 health situation, many meetings and events are being rescheduled or canceled. Please visit the listed websites frequently for updates.

The Ohio State University Manure Science Review August 10, 2021 Celina, Ohio Details: Cattle Industry Convention and National Cattlemen’s Beef Association (NCBA) Trade Show August 10 to 12, 2021 Nashville, Tenn. Details: University of Minnesota Extension Manure Composting Workshop August 11, 2021 Morris, Minn. Details: manurecomposting U.S. Poultry & Egg Association’s Environmental Management Seminar September 16 and 17, 2021 Destin, Fla. Details: educationprograms

Trident Processes Inc.

Industrial Solutions


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Journal of

Nutrient Management Visit us online at: WWW.JOFNM.COM

World Beef Expo September 23 to 26, 2021 Milwaukee, Wis. Details: World Dairy Expo September 28 to October 2, 2021 Madison, Wis. Details: 2021 Sustainable Agriculture Summit November 17 and 18, 2021 Las Vegas, Nev. Details: If you would like us to include your event on our list, please send details to

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ou’ve got a problem, and we’ve got the solution!” How many times has that statement made you bristle? Often, we deny that we have a problem but readily admit better solutions might be out there. Ever since the invention of the pitch fork, farmers have been hunting for better ways to deal with manure. We’ve come a long way with manure handling, but processing is where dreaming occurs. I should know, having three patents myself ranging from sand removal to making hog manure solid to a series of separation and treatment processes acting in synergy.

I’m not saying that any of these are not true (except the disappearing nutrients one — only organic matter, nitrogen, and pathogens can actually be eliminated). However, these statements prompt further in-depth questioning.

Skin in the game The dynamics of manure processing have recently changed. One of the no-go items for many failed projects was farmer investors — either as individuals or collectively. Now the financial

end up getting back some, if not all, of the nutrients after they got what they wanted out of your manure.

Keys to success I have identified the following for successful manure treatment technologies: costs justifiable, moving parts minimized, concept understandable, operational costs low, inputs minimal, and operation management fool-proof. Most manure treatment technologies offered are an attempt to adapt an industrial technology to agriculture. Very little is “new,” only the application. We have been able to get liquid manure to drinking water standards for years, but at what cost and what management does it take? At the end of the day, there are still nutrients to land apply or discharge (if the permit allows).

Worth another look You need to ask the hard questions. Does the manure processing proposal pass the “smell test”? I find that many of the spokespeople looking to find a place

Questionable claims

Ever since the invention of the pitchfork, farmers have been hunting for better ways to deal with manure.

These are the statements that raise red flags for me when I hear them in sales pitches: • Everyone is going to have to process manure. Land application of manure will soon be banned. • We can make phosphorus disappear. • After treating the manure, we can turn it into a valuable fertilizer. • We are in discussions with (name of lawn fertilizer company here) to purchase the end product. • The Environmental Protection Agency (EPA) loves our process. • We’re going to build a community processing plant and take all of the manure in the surrounding area, and we will even pay for it. • It’s a European technology, and we’re going to build these all around the U.S.

burden is coming from investors outside of agriculture. They will pay for the project, manage it, and may even pay for the manure. The main drivers appear to be green energy initiatives that have an appetite for pipeline methane and organic food production needing organic-derived fertilizers produced on a commercial scale. I am involved with a handful of those currently. This takes most of the risk from the farmer, and what you get in return is negotiated. We have always preached that manure nutrients are very valuable. But at what cost and risk? We have to be careful that our greed doesn’t mask the real value of letting manure go so we can just get back to milking cows or raising pigs. Of course, you may still

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for their company’s project have their sales points but may be a little lean on technical information. If it sounds too good to be true, it very well could be. It has become obvious that as farms get larger, their manure nutrients must be recycled in a broader area. This means the manure must become more portable. Potential paybacks associated with green energy production, coupled with outside management and investment, plus more user friendly manure creates opportunities worth a closer look. ■

The author is the president of Menke Consulting LLC, an agronomic and environmental consulting firm in Greenville, Ohio.

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