Journal of Nutrient Management - Quarter 1 - 2020

February | 2020

Published by W.D. Hoard & Sons Co.

Journal of

Nutrient Management

10 16 22 JNM Q1 2020 Cover.indd 1

Connecting the dots with manure Managing nutrients in cold climates Use the four R’s to guide your application strategy

1/24/20 3:53 PM

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Separator GREEN BEDDING Screen size: 0.75 / 1.0 mm 3.3-780 HD Capacity up to 3 cubic yards of bedding material per hour

Dry matter content Input power ▪ New robust cage and XC wearing screen MAGNUM MSXH MAGNUM Screen size ▪ Including control panel

CSPH

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up to 38% max. 15 HP 0.75 / 1.0 mm MSXH Submersible motor mixer

BAUER NorthNorth America, Michigan City, Indiana 46360,Michigan PO Box 8943 BAUER North America, City, Indiana PO Box 8943 BAUER America, PO Box 8943, Michigan City, Indiana 46360 •46360, 800 922-8375, sales@bauer-at.com, www.bauer-at.com/en +800 922-8375, sales@bauer-at.com, www.bauer-at.com/en +800 922-8375, sales@bauer-at.com, www.bauer-at.com/en

CONTENTS

Volume 1 | No. 1

4 From problematic

22 Use the four R’s to guide

to promising

your application strategy

6 Face manure challenges

DIRECTOR OF MARKETING John Mansavage

24 Farming for a better

ADVERTISING SALES Wendy Clark wclark@hoards.com

future

28 Poultry litter brings long term benefits

30 Tracking down the

with manure

32 Relationships and hope fuel the new year

First Thoughts . . . . . . . . . . 4 In the Field . . . . . . . . . . . . 6

18 Less methane by 2030

Policy Watch . . . . . . . . . . . 8

20 Cover crops can be

On the Move . . . . . . . . . . 32

a bridge

Manure Minute . . . . . . . . . 14

F2 3 Q1 2020 Contents.indd 1

ADVERTISING COORDINATOR Patti Kressin pkressin@hoards.com

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

Places To Be . . . . . . . . . . 34

Photo by Jim Baltz, Pesotum, Ill.

jofnm.com

Kim Zilverberg kzilverberg@hayandforage.com

Fresh Paint . . . . . . . . . . . 33

ON THE COVER As farms grow, so does the volume of manure produced.

Manure storages, such as the concrete lagoon shown here, have become an integral part of a livestock farm’s footprint.

We must have an environmentally friendly way to contain these nutrients until we can make use of them through application or other treatment options.

Find us online at: www.jofnm.com

Jenna Zilverberg jzilverberg@hayandforage.com

W.D. HOARD & SONS PRESIDENT Brian V. Knox

DEPARTMENTS

in cold climates

Andy Dellava adellava@hoards.com

Jane Griswold jgriswold@hoards.com

nitrate source

16 Managing nutrients

Nutrient Management MANAGING EDITOR Abby Bauer ART DIRECTOR Todd Garrett EDITORIAL COORDINATOR Jennifer Yurs

by understanding risks

10 Connecting the dots

Journal of

facebook.com/JournalofNM

twitter.com/JournalofNM

Journal of Nutrient Management (ISSN# Pending) 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@ jofnm.com Website: www.jofnm.com. Postmaster: Send address corrections to: Journal of Nutrient Management, PO Box 801, Fort Atkinson, Wisconsin 53538-0801. Tel: (920) 563-5551. Email: info@ jofnm.com. 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, Email:info@jofnm.com.

Copyright ® 2020 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.

February 2020 | Journal of Nutrient Management | 3

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FIRST THOUGHTS

FROM PROBLEMATIC TO PROMISING T

Abby Bauer Managing Editor

here is no doubt about it; the agriculture landscape has changed. Farms have grown, evolved, modernized, and specialized. Each decade brings new ideas and new outlets for farmers to better care for animals and the land.

This certainly holds true for nutrient management, and more specifically, manure. What was once considered a waste product, spread on fields closest to the barn to “get rid of it,” has become an opportunity for today’s farmers. Yes, handling manure can still be difficult, but there are now more options to get value from this plentiful resource than ever before. Fertilizer, energy, bedding, even drinkable water — these are all products that can be derived from manure.

And let’s be honest. Just as livestock farmers have a responsibility to care for their animals, they also have an obligation to manage manure in a way that protects not only their farm, but the natural resources that surround them. Nutrient application that meets the needs of the crops is a smart business decision that also protects waterways and the groundwater we all depend on.

While manure itself may not be a glamorous topic, handling it is a necessity, and the opportunities we have now — and those that will be developed in the future — are pretty incredible. That is the reason our team decided to focus in on this crucial matter and launch a quarterly magazine, the Journal of Nutrient Management. We want to bring insightful information from respected sources to you — the individuals working every day to properly store, handle, and utilize the manure produced by cattle, hogs, and poultry.

While this is the very first issue of the maga-

zine, our roots in agriculture and publishing run much deeper. For 135 years, the W.D. Hoard and Sons Co. has published Hoard’s Dairyman, an industry-leading magazine about dairy production. It’s offered in four languages with readers in more than 50 countries around the world. Then, five years ago, we added Hay & Forage Grower to our portfolio, a respected magazine focused on producing and utilizing high-quality forages.

We also write with a practical perspective.

It was important to our founding father, W.D. Hoard, that his editors remain connected to the magazine’s readers and the dairy industry. That was one of the reasons the agricultural leader and former governor purchased a farm just outside of Fort Atkinson, Wis., in 1899. Now, more than a century later, we continue to own and operate the Hoard’s Dairyman Farm. Located just a mile from our office headquarters, that part of our company is a constant reminder to our entire team of the challenges and triumphs faced by our fellow farmers. It gives us a front row seat to all aspects of production agriculture, including manure management.

Let’s move forward together, as partners in agriculture, and explore all the opportunities available to turn manure from waste into something worthwhile. Thank you for picking up this first issue, and we look forward to serving as an information outlet that can help us all make better use of this nutrient source moving forward.

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: abauer@jofnm.com.

4 | Journal of Nutrient Management | February 2020

F2 4 Q1 2020 First Thoughts.indd 2

jofnm.com

1/17/20 9:36 AM

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IN THE FIELD

FACE MANURE CHALLENGES

BY UNDERSTANDING RISKS Farms can mitigate the chance of runoff by avoiding application during high-risk time periods.

by Amber Radatz

Answers from on-farm research To help farmers navigate these challenges, there is Discovery Farms, a farmer-led research and outreach program of the UW-Madison Division of Extension focused on the relationship between agriculture and water quality.

The Wisconsin-based program works on privately owned farms throughout the state to conduct unbiased research.

Our neighbor and close partner, Discovery Farms Minnesota, is coordinated through the Minnesota Agricultural Water Resources Center. Data collection methods from both states are compatible in order to capitalize on combining data and create a robust set of on-farm water quality data to inform

The highest risk Runoff is mostly likely in late winter months like February and March and spring months like April, May, and June. In November, December, and January, the average monthly surface runoff is less than 0.1 inches. However, February and March average 0.4 and 1 inches, respectively. The average monthly runoff for March is twice as high as the next closest month (June) and almost three times higher than February, April, May, and July.

There is less risk for runoff in November, December, and January, and this relates to the amount of precipitation

Average monthly runoff from sites in Minnesota and Wisconsin

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runoff earlier in the winter compared to later in the season.

farmers on topics like manure management, soil erosion risks, and other crop nutrient questions.

Managers of manure in the Upper Midwest or other seasonally frozen areas must take into account the two main runoff periods in winter (February and March) and spring (April, May, and June). Discovery Farms has worked with over 100 farmers in Wisconsin and Minnesota over the past 19 years to understand the challenges and solutions in the intersection between agriculture and water quality. Wisconsin and Minnesota farms are included in this information, which consists of 250-plus site years of data. The on-farm research data helps to show the stark differences in the risk of

Average monthly runoff (in)

T

he manure application challenges of previous generations were certainly different than the challenges of today.

We now have equipment that can haul manure for more miles and under varying conditions. Gone are the days that the distance traveled was mostly determined by the day’s weather and whether the spreading tractor had a cab or not. Today’s challenges are often related to unreliability of the nutrient content and release, field compaction, cost, and finding the “right time” to spread manure onto the field for environmental concerns.

0.97

1.0 0.8 0.6

0.46

0.4

0.36

0.32

0.27

0.29

0.2

0.15

0.09

0.0

Jan

0.06

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

0.03

0.03

0.06

Oct

Nov

Dec

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during that time period as well as the risk of snowmelt or rain. The average date that the soil freezes is December 9, according to Discovery Farms soil temperature observations. There is rain and/or snowmelt in November, but rain or melting snow during November is more likely to infiltrate into the soil than rain or snowmelt during February and March when the soil is frozen or only partially thawed. The average thaw date is March 28.

One of the drivers of dissolved phosphorus loss in the winter is manure application, especially manure applied shortly before runoff or during late winter. Phosphorus is a valuable manure nutrient for crop production, but it is a concern for water quality as it creates algal blooms and excessive plant growth, harming the fishery and recreational resources. Manure application during February and March significantly elevated dissolved phosphorus loss when compared to manure application earlier in the winter or other times of the year.

Manure application during the time period when runoff is more likely raises the risk for nutrient loss associated with runoff. Research has indicated that when manure does not have time to adhere to the soil, dissolved phosphorus

loss can increase by two to four times.

Applying manure onto a snowpack or shortly before the snowmelt, especially later in the season, leaves little chance that manure will make contact with the soil and a greater chance that nutrients will be lost in runoff.

Farmers must adjust Concerns with winter spreading can be addressed if farmers understand the risks associated with varying soil conditions and consider weather forecasts prior to spreading on frozen ground.

Spreading just before snowmelt or a winter rain event significantly raises the risk of manure and nutrient movement. The key to reducing nutrient loss during winter manure application is to understand the local conditions and have a detailed spreading plan in place for winter and throughout the year.

Working to apply manure during a low risk time period can mean that farmers need to alter rotations or consider options that allow them to manage manure during the lowest risk time periods. Especially for farmers with stored manure, managing the storage throughout the year is the best practice to make sure there is no ‘need’ to spread when conditions are ripe for runoff.

Utilizing other tools, like the Runoff Risk Advisory Forecast in Wisconsin, allows farmers a real-time look at the runoff risk no matter the season. This forecasting tool is a joint effort by several state agencies, including Discovery Farms and other state and federal partners. Investigate the options available for your area, and work to utilize the best tools available to reduce the risk of loss from winter manure application. â– For more information about the Discovery Farms Programs in Wisconsin and Minnesota, visit www.uwdiscoveryfarms. org or www.discoveryfarmsmn.org.

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

Frozen soil dissolved phosphorus loss (lb/ac)

Phosphorus loss on frozen soils 5

No winter manure application Early winter manure application (Dec-Jan) Late winter manure application (Feb-Mar)

4 3 2 1 0

0

1

2

3

4

5

Frozen soil total phosphorus loss (lb/ac) Dissolved phosphorus drives phosphorus loss on frozen soils, and late winter manure application can increase losses by two to four times compared to early winter application or no winter application. Manure application on frozen ground shortly before a snowmelt or rain drives the largest losses. jofnm.com

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POLICY WATCH

MICHIGAN Michigan’s Concentrated Animal Feeding Operation (CAFO) General Permit is under a routine five-year revision by the Department of Environment, Great Lakes, and Energy (EGLE). The permit, which applies to about 260 farms in the state, was last updated in 2015 and expires on April 1, 2020.

After meetings held last spring with agricultural, environmental, and local government groups, proposed updates to the pollution discharge permit for CAFOs were issued in late October. Among the more notable changes would be a ban on spreading manure in January, February, and March.

Three public hearings were held in December to address community concerns, and the public was invited to submit comments about the proposed updates prior to December 18, 2019.

develop groundwater sustainability plans (GSPs), and manage groundwater for long-term sustainability.

In the SGMA 2019 Basin Prioritization, 94 basins and/or sub-basins were identified as medium or high priority. These 94 basins, when combined with adjudicated areas that have existing governance and oversight in place, account for 98 percent of the pumping (20 million acre-feet), 83 percent of the population (25 million California residents), and 88 percent of all irrigated acres (6.7 million acres) within the state’s groundwater basins.

The California Department of Water Resources (DWR) was first directed to prioritize basins as part of the Groundwater Monitoring legislation enacted in the state’s 2009 Comprehensive Water Package. Past prioritizations were conducted in 2014 and 2015.

MARYLAND

CALIFORNIA Basin prioritization is a technical process that uses the best available data and information to classify California’s 515 groundwater basins into one of four priority categories: high, medium, low, or very low.

The most recent basin prioritization was completed in December 2019.

The process of prioritizing basins is based on eight components identified in the California Water Code Section 10933(b).

Each basin’s priority determines which provisions of California Statewide Groundwater Elevation Monitoring (CASGEM) and the Sustainable Groundwater Management Act (SGMA) apply to it.

The SGMA requires medium- and highpriority basins to develop groundwater sustainability agencies (GSAs),

Maryland Agriculture Secretary Joseph Bartenfelder took counsel from an advisory committee and said he saw no need to hold up a regulation restricting the use of animal manure as fertilizer. The 19-member advisory group opposed a one-year delay in restrictions being imposed in the coming year after a study by Salisbury University found the state was not prepared to deal with the excess manure that could result.

The restrictions would affect more than 1,300 farms in the state. A majority of the acres that would be impacted by the rule are on the state’s Eastern Shore where poultry manure is widely used as fertilizer.

The Phosphorus Management Tool recommendation that was adopted in 2015 restricts or prohibits the application of phosphorus on fields where runoff is a risk. Currently, about 65,000 acres on 350 farms fall under the restriction, which was applied initially to fields with the highest soil phosphorus levels. Once the phase-in period is complete on January 1, 2022, about 228,000 acres on 1,600 farms statewide will be required to comply.

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The state has a transportation program in place and currently hauls about 250,000 tons of manure annually to other farms. Each year, $1 million is provided to farms to subsidize the transportation, while another $400,000 is contributed by poultry companies. The study predicts more funding will needed, upwards of $3.5 million annually, to handle the additional manure that needs to be transported.

WISCONSIN The Wisconsin Department of Natural Resources (DNR) board granted the agency permission to begin drawing up manure and fertilizer restrictions for areas prone to groundwater pollution. Despite concerns from the agricultural community, the board gave the department the green light on a 5-to-1 vote in mid-December.

The DNR released a broad outline of the restrictions last fall. These restrictions would be similar to those already in place in 15 northeastern Wisconsin counties as a result of drinking water contamination in the state’s Kewaunee County that has significant land masses with karst topography. The proposal would impose these regulations for manure and fertilizer in yet to be defined sensitive areas with highly permeable soil in other parts of the state.

It may be months before the department completes a draft, and the final regulations would need legislative approval.

SPAIN Manure was used in a protest outside of a United Nations’ (UN) Climate Change Conference in Madrid, Spain. Activists dumped a load of horse manure outside the meeting location to demonstrate their frustration with world leaders over global warming. jofnm.com

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+ $

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All photos: Abby Bauer

Connecting the dots with manure The owners of Five Star Dairy strive to be better than average — and that includes manure management on their Wisconsin farm.

by Abby Bauer | Managing Editor

O

ne only has to spend a few minutes with dairyman Lee Jensen to realize that his mind is always moving. He is continually crunching numbers and considering options, looking for the next opportunity to benefit his cows, his fields, and the farm’s bottom line.

This is especially true when it comes to the manure management on Jensen’s dairy operation near Elk Mound, Wis. From anaerobic digestion to a bedding dryer, his commitment to not only removing manure but making 10 | Journal of Nutrient Management | February 2020

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it a useful byproduct has led him down several paths that have proven successful on his family’s farm.

Cows at the core Jensen grew up on a registered Holstein farm in the northwestern part of the state, which was started by his grandfather and later run by his dad and uncle. Jensen began farming full time after graduating from high school and took over the operation with his cousin Jim in 1989.

Jensen’s wife, Jean, is a veterinarian, and she was also jofnm.com

1/17/20 9:40 AM

managing her family’s dairy farm when they got married in 1996. The three contemplated building another dairy for a few years, and in 2000, they purchased some land and did just that.

The first cows were milked at Five Star Dairy on November 28, 2000. Another freestall barn was added in 2009.

In addition to the 1,100-cow milking herd, the Jensens raise all of their heifers, which are housed on the farm, at the old home farm, and at Jean’s family’s farm. They crop 4,500 acres to grow corn, alfalfa, and soybeans.

The Jensens also run a trucking business. They haul raw milk for 50 dairy farms to ConAgra Foods, and they also transport processed milk product. In addition to milk, they haul whey permeate from the milk plant, distillers grains from an ethanol plant, and sawdust.

Jim manages the trucking business and the crops, while Jean fills the herd manager role and does veterinary work for the farm. Lee is the general manager who oversees feeding and heifer raising.

While the family has diversified its business, “Cows are the heart and soul of what we do,” Jensen said. “We try to provide good feed and do what’s good for the land.”

Open to a digester The same year he started Five Star Dairy, Jensen toured a farm in Minnesota that had an anaerobic digester, and he liked what he saw. When he returned home, he asked to have a meeting with Dunn Energy Cooperative and Dairyland Power and told them he’d be interested in producing electricity someday. Three years later, working with Microgy Inc. and Dairyland Power Cooperative, an anaerobic digester was installed on his farm in 2005.

At that time, not many dairy farms had digesters and manure solids separators. As the first digester for Dairyland Power, Jensen said he was a bit of a guinea pig. He was also one of the first farms to co-digest different substrates in his digester. Jensen learned a lot about anaerobic digesters over time, and he pointed out different aspects jofnm.com

F2 10-13 Q1 2020 Five Star.indd 3

of the digester that he can monitor and control from multiple computers around the farm and his phone.

When it comes to profitability, Jensen said, “Over time, the digester has had high and low points.” He explained that, in general, power companies want renewable energy; solar and wind power are more feasible long term.

Technology and mass production are making the electricity they produce more economical for all consumers.

Jensen had a long-term contract with Dairyland Power, so he continued to run the digester and make methane even when the demand wasn’t there.

Then, about four years ago, the company offered a buyout and he accepted it.

Serving on the Dunn Energy Cooperative board of directors gave Jensen a deeper perspective on energy production. “Making electricity just isn’t feasible at the current revenues,” he said. “We have good, reliable electricity here in the United States, and they are not going to pay us enough to make the digester profitable.”

He is in the early stages of working with another biogas company to produce CNG (compressed natural gas) vehicle fuel, which he thinks will be a more cost-beneficial outlet for his anaerobic digester in the future.

Turning manure into bedding Beyond electricity, the anaerobic digester opened the door to another bedding source for their cows. The freestalls at Five Star Dairy were originally bedded with sawdust, of which they had an ample supply, but Jensen was looking for an opportunity to switch to deep bedding. The farm is not, however, set up for sand separation, he said. “It would have been too expensive to switch to sand and a nightmare to convert our system to it,” he explained.

What they could use, however, were the digested manure solids that come out of the digester. He installed his first manure screw press separator in 2006, then years later added a second one, which gets the manure solids drier when they leave the press.

Separated manure solids leave Jensen’s bedding dryer at 45% moisture and are ready to fill their deep-bedded freestalls.

Manure solids are separated 24 hours a day, and 50 to 100 pounds of solids bedding are produced per minute. The solids go into the separator in a slurry form. The liquid goes into the manure storage pit and the solids come out at 70% moisture.

While these manure solids were comfortable for the cows, “I couldn’t get somatic cell count as low as I wanted, and there was too much clinical mastitis,” Jensen said. After some thought, he identified what he believed was the missing link.

“My gut feeling was that we needed to put in a dryer,” Jensen explained. He started doing research to see what was on the market.

Jensen decided on a stainless steel, triple pass rotary drum bedding dryer manufactured by McLanahan. It cost a little more, he said, but it is also more efficient. Additionally, it has more safety controls in place, including a fire suppression system, which Jensen appreciated. The system automatically injects water into the dryer if the temperature gets above a predetermined set point, shuts the system down, and alerts Jensen.

Since his was the first biosolids dryer installed on a farm, there was no data he could find to consider, but the dryer came from a reputable company and he had a good feeling about it. He worked with Komro Sales, the local McLanahan dealer, which was the same company that had previously installed their manure pumps and separators. The dryer was installed just over two years ago, and Jensen has been very pleased with the results.

After the manure solids leave the

February 2020 | Journal of Nutrient Management | 11

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average somatic cell count went from 204,000 to 109,000 cells per milliliter.

Producing high-quality milk while using manure solids as bedding is very important to Jensen. Mastitis hurts reproduction and raises antibiotic use, he said. The dryer is part of the puzzle in maintaining herd health, and he feels their additional milk premiums cover the separation and dryer costs.

“The extra 2,000 pounds per cow per year is great, too,” Jensen added.

“I feel good starting up the dryer every day. It makes everyone else’s job on the farm easier,” he said. “The operational costs are significant, but the benefits outweigh that. I wish I would have done it sooner.”

When looking for a bedding option besides sand, Jensen installed his first screw press nearly 15 years ago. Today, two presses separate manure solids on their farm 24 hours a day. separators, the fibers are moved with conveyor belts into the bedding dryer’s hopper, which is like a TMR mixer.

Jensen explained that this ensures even feeding into the dryer. This is not necessary, but the bedding dries more efficiently when the dryer is fed evenly.

Bedding is dry after three to four minutes in the dryer, where it is exposed to temperatures up to 1,000°F, and is discharged at 142°F. The bedding leaving the dryer is about 45% moisture, and tests prove that pathogens are greatly reduced. A conveyor stacks the bedding on a pile once it leaves the dryer, and it is immediately ready for use.

The dryer can run on natural gas, propane, or a combination of the two.

It can use methane from the digester as well. Jensen explained that it is less expensive to run in the summer when it is warmer outside and they can use natural gas. In total, electricity costs $4 per hour to run the dryer, separators, and conveyors. The fuel costs range from $6 to $20 per hour.

The dryer is running 10 to 12 hours per day. If not able to visit the separation building physically, Jensen will check the dryer through cameras or an app on his phone every hour to make sure everything is working properly.

Overall, though, the dryer operates with little maintenance.

The cows have spoken

Once they installed the bedding dryer, the Jensens converted more of their mattress stalls to deep bedding. They are filled with the dried manure solids four times per week, and the cows seem to prefer them.

“The cows in the deep beds are doing better,” Jensen said. “They lie down more.”

The bedding material doesn’t give the same grip that sand does, so Jensen added more floor grooving in the barns for that reason. In the stalls, though, it is certainly doing its job.

“There’s a cost to running the dryer and it’s another thing to watch, but in my mind, there’s no question that it’s better for the cows,” Jensen said. “It’s softer; the wet bedding packed so hard.

It’s dry enough it doesn’t freeze. I’m pretty sold on it.”

The results of improved cow comfort have shown up in the bulk tank. Five Star Dairy started using the dryer at the end of 2017, and the herd’s annual average for energy-corrected milk went from 89.9 pounds to 96 pounds per cow.

During the same time frame, their

12 | Journal of Nutrient Management | February 2020

F2 10-13 Q1 2020 Five Star.indd 4

Benefits of composting The bedded solids have worked very well for the farm, but they still had that affordable supply of sawdust. Jensen decided to build a compost bedded pack barn for far off dry cows, bred heifers, and prefresh and postfresh animals.

“They love it,” Jensen said. “They stay clean. They are comfortable.” The herd health benefits have been positive, too.

In four years, he said they have only had one displaced abomasum.

Maintaining a 30,000-pound herd average goes beyond bedding, of course. Cows are grouped by age and size in his three freestall barns, and stalls vary in width to accommodate the different sizes of cows. In this newest barn, the stalls are 50 inches wide with more lunge space.

They utilize rumination and activity monitors to further monitor herd health. Even though reproduction rates are not quite as high as Jensen would like, they have plenty of heifers coming down the pipeline. This means they can be pickier about the heifers they keep.

“We want to make enough heifers, but we want to have the best heifers,” he said. Heifers are bred twice to sexed semen, once to beef semen, and then they are culled if not pregnant.

Changes made to their facilities have also shown up in the milking herd’s cull rate, which is down 10% from what it was just a few years ago. The new jofnm.com

1/16/20 11:15 AM

rain out of the lagoon. At a minimum cost of a penny per gallon, that is 1.5 million gallons of liquid that did not have to be pumped out of the lagoon.

Better than average

Jensen is able to keep a close eye on his anaerobic digester and bedding dryer using programs on his computer and cellphone. compost-bedded pack barn definitely deserves some of the credit for that, along with the drier bedding in the stalls.

Improving the soil

While recycled manure is put to good use in the barn, manure is also seen as a valuable asset for their crop fields.

The Jensens haul their own manure, using drag hoses for close fields and trucking to those that are more remote.

Jensen said they have three nutrient management plans to maintain their fields. By using more modern equipment, he feels the soil is in much better shape than it used to be, and crop yields continue to improve.

Some of the separated manure solids are headland stacked on fields that need extra phosphorus. Jensen said it’s particularly good for sandy ground farther away from the dairy. The manure and bedding from the compost-bedded pack barn is also stacked in the fields and used as fertilizer.

Additionally, Jensen has been marketing compost since he started running the digester in 2007. People come out to get compost for their gardens, and it is a chance for them to see the dairy. Money made from selling compost covers the farm’s cost of sawdust, but it’s also an educational opportunity.

“These customers are consumers,” he said, indicating the value of having them personally know a working dairy farm.

“There is so much misinformation out there.” The Jensens are eager to educate and open their doors frequently for tours.

There is no shortage of diversification and innovation on Five Star Dairy. And behind the technology is Jensen, who keeps a close eye on all aspects of the dairy using computers and his smartphone. He commented on the value that technology brings when combined with good cow sense.

“You still have to go in the barns to look at the cows,” he said, “but milk production and some of the other numbers we can track are things you can’t see in the pens. It goes both ways.”

When the Jensens stopped using BST a few years ago, the herd actually went up in milk production. Jensen credits that to their commitment to do other things better.

“Our goal is to always get better,” Jensen said. “You’re never going to make money if you are average.”

Adding an anaerobic digester set into motion many changes on the farm, with manure management and beyond. Jensen has built an arsenal of knowledge and contacts since then, which continue to improve his dairy.

“The more dots you can connect, the more competitive you can be,” he explained. ■

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Yet another benefit of using the dried manure solids as bedding has shown up in the area of manure storage. When they were bedding with sawdust, Jensen said it took two agitators, a pump, and three tractors to clean out their 9 million-gallon manure storage pit. By keeping the solids out, it takes a lot less equipment to empty the pit now as they don’t have to agitate it, and it doesn’t plug up the trucks.

Another feature that reduces the volume in their manure storage is a heavy plastic lagoon cover. Jensen participated in an odor study and got some funding for the cover a decade ago. “It was not cheap, but I am really glad I did it,” Jensen said. The cover has a 20-year guarantee, and after 10 years, it has yet to show wear. “There is no odor, and it enhances storage immensely,” he added.

Just last year alone, Jensen estimates it kept 42 inches of jofnm.com

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1/16/20 11:15 AM

MANURE MINUTE

WHEN MANURE MOVES, WHO IS RESPONSIBLE?

BEST PRACTICES FOR EMERGENCY APPLICATION

C

A

oncentrated animal feeding operations (CAFOs) must maintain accurate manure handling records to meet the requirements of their nutrient management plan (NMP). If a farm doesn’t have enough land to utilize all of its nutrients, it is common for manure to be moved to a neighboring farm for land application.

When manure moves to a new location, who is legally responsible for managing that manure may change.

Other potential owners could be the person or entity transporting and/or applying the manure, or the owner of the farm receiving the manure.

If ownership switches from the original farmer to someone else, that would be considered a manure transfer, explained Amy Millmier-Schmidt in a University of Nebraska-Lincoln UNL Water newsletter.

She highlighted these three questions used to determine if a manure transfer has taken place: 1. Is the land that is receiving the manure owned by the concentrated animal feeding operation’s (CAFO) owner?

If yes, then a manure transfer did not take place, because the CAFO operator still controls how the manure is utilized. She pointed out that this land should be part of the CAFO’s NMP. Even if an employee or a custom manure applicator transported the manure, a manure transfer did not take place in this scenario.

2. Is the land receiving the manure included in the CAFO’s NMP under an agreement between the CAFO operator and the farmer who owns the land?

Since this land is included on the CAFO’s NMP and the CAFO operator dictates how the manure is used, a transfer of manure does not happen in this instance, either. Application should follow the protocols specified in the NMP. 3. Who is applying or directing manure application?

If the receiving farmer decides where, when, and how the manure is utilized, and the CAFO owner is not involved in that decision process or the actual application, then this is considered a manure transfer. The original owner no longer determines how the manure is used.

When a manure transfer occurs, Millmier-Schmidt wrote that the CAFO operator should maintain a record of how much manure was transferred, when it took place, and the name and address of the recipient. This person should also provide the recipient with an analysis for the manure being transferred.

14 | Journal of Nutrient Management | February 2020

F3 14-15 Q1 2020 Manure Minute.indd 2

s we approach the end of winter, farms across the country could soon be dealing with melting snow and heavy spring rains. These weather situations can create challenges when it comes to manure storage structures.

Ideally, a farm’s manure storage would have enough capacity to handle extra rainfall if it should occur.

However, if you find yourself in a situation where space is limited, South Dakota State University’s Extension Water Resources Field Specialist David Kringen shared these practices for when emergency manure spreading is necessary.

1. Look for opportunities to transfer to satellite storage or to a neighboring facility.

2. Apply only on fields with a low risk of runoff as indicated in your approved nutrient management plan.

3. Spread on fields that have crop residue such as cornstalks, cover crops, or hay crop residue as they are lower risk than fields that have already been tilled or only have corn silage stubble.

4. Try to inject or incorporate manure where practical.

5. Consider temporary barriers such as a small earthen dike or hay or straw bales at high-risk points.

6. If applying on frozen soil, stay on fields with slopes of less than 4%.

7. Do not apply on floodplains.

8. Maximize set-back distances from streams, watershed areas, or fields with surface inlet areas.

9. Take manure and soil samples and calculate a rate to make sure overapplication does not occur.

10. Monitor soil conditions continuously to make sure soils do not become saturated.

11. If applying to thawed soils, the tops of slopes are usually lower risk.

12. Avoid application in fields where water runoff typically occurs.

13. Work with the appropriate regulating agency to activate your emergency response application plan.

Kringen also encouraged farms to have an emergency response plan in place in case a storage spill, leak, or failure should occur. He said plans should contain phone numbers for the county sheriff and fire department, the local zoning officer, your engineer, and your state’s Natural Resource Conservation Service and Department of Natural Resources.

jofnm.com

1/16/20 10:47 AM

STOCKPILES PLACED IN WINTER LEACHED MORE

S

hort-term manure stockpiles in fields are one opportunity for some farms to expand their manure storage capabilities and reduce hauling time in the spring. One concern, though, is the leaching of nutrients into the soil.

A study done by Utah State University researchers examined stockpiles placed in November, January, and March over a five-year time period.

Their results were presented in a poster at the American Society of Agronomy (ASA), Crop Science Society of America (CSSA), and Soil Science Society of America (SSSA) International Annual Meeting last November.

Solid manure samples were collected as the stockpiles were created, and then again when the manure was removed for land application. The samples were tested for phosphorus, ammonium nitrogen, and nitrate nitrogen. Leachate was collected biweekly under the manure staging areas and was analyzed for ammonium nitrogen and nitrate nitrogen.

Soil samples were also taken prior to manure placement and after removal.

Two types of manure were studied — dairy manure with straw and dairy manure without straw. It was found that manure stockpiles containing

straw produced less leachate than stockpiles without straw.

As far as timing, significant leachate was produced under the stockpiles placed in the winter months (January and March). The preliminary results showed that the November application produced the least leachate and the lowest total nitrogen loss. Because of Utah’s dry climate, the manure may have dried out in the late fall months, enabling it to absorb more moisture.

Piles placed in January produced the most leachate and had more total nitrogen loss. Snow and snowmelt likely contributed to this.

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Managing nutrients in cold climates

Opportunities to avoid manure application during winter months can minimize losses and improve nutrient uptake.

by Eric Young

C

rop production in Northern regions is characterized by short growing seasons and seasonally high runoff potential. Soils warm slowly in the spring with extended periods of wetness, posing crop production and environmental risks.

Nutrient use efficiency (NUE) is the relative amount of applied nutrient that ends up in a crop. It varies widely by crop, weather, fertilization methods, and others factors.

Applying manure to actively growing crops (after hay cuttings or to cover crops, for example) or immediately prior to planting annual crops like corn can improve NUE and reduce losses. Methods of application also impact manure NUE. From an NUE standpoint, applying manure in late fall, winter, and early spring (often termed the nongrowing season) is not ideal. Soils are generally wetter with higher runoff potential and depressed soil biological activity. In addition, freeze-thaw transitions have a major impact on runoff potential and nutrient movement. Frozen soils allow minimal infiltration and can elevate dissolved phosphorus (P) mobility to surface water with rapid snow melting.

Surface runoff and erosion processes drive both topsoil and P loss in many places. Mitigating surface runoff from field nutrient source areas is critical to maintain soil organic matter and crop productivity and for reducing nutrient runoff risk, particularly for farms

Control

8% solids

15.4% solids

Figure 1. Dairy manure applied at the same rate (2,852 gallons per acre) and source but at differing solids content spanning the range of liquid to semisolid manure. Small plots were used to isolate and measure snowmelt runoff. Pictures by Eric Young and Jessica Sherman. adhering to water quality regulations.

Snowmelt accounts for a substantial amount of the annual water budget and surface runoff in cold climates. While manure application to frozen, saturated, or snow-covered soils is discouraged in general for agronomic and environmental reasons, manure is still routinely applied under a wide range of weather conditions, including close to the onset and during the nongrowing season.

Many dairy operations have a limited number of fields that can reasonably receive manure and often have a need to fall-apply manure to fields with or without a cover crop. Fall-applied manure remains close to the soil surface where it is exposed to freezing temperatures followed by variable melting events as spring approaches. Manure nutrients in surface soil interact with melting snow, releasing nitrogen (N) and P. Applying manure to a growing crop (hayfield or cover crop) using low-distur-

16 | Journal of Nutrient Management | February 2020

F3 16-17 Q1 2020 Cold Climate.indd 2

5% solids

bance methods can reduce both soilbound and soluble nutrients. However, some level of nutrient runoff is inevitable, depending on the amount of runoff and soil N and P concentrations. Large storm events during the growing season can contribute to annual runoff losses, but losses during the nongrowing season are important to recognize in cold climates.

Available surface area for sorption and other nutrient attenuation mechanisms are compromised in frozen or partially frozen soils. The how (what method, rate, and incorporation level) and when of manure application in relation to weather and soil conditions is a critical aspect of trying to better predict runoff nutrient loss risk from manure.

The manure matters, too While multiple field-related factors (soil type and drainage, hydrology, manure application method, crop system, and tillage intensity) affect jofnm.com

1/17/20 9:47 AM

actual runoff and manure nutrient loss, manure itself also plays a role.

Livestock manure varies in physical and chemical form. In general, liquid manures (less than 6% solids) have lower nutrient content and behave more like a liquid than a solid, making them vulnerable to runoff losses under wet conditions.

Manure’s flow resistance (viscosity) goes up rapidly when a higher solids content exists with a marked difference in form and ease of flow (Figure 1).

Since dry matter mass rises with solids content for a given manure source, total N and P rate applications also go up (per unit of volume applied). With this logic, applying higher solids content manure raises total nutrient application, but in a form less vulnerable to runoff flows. It is important to determine how changes in manure solids affect manure nutrient mobility and runoff nutrient losses when applied in different conditions.

an evolving science. Farms should focus on applying manure closer in time to crop growth and to unfrozen soils without snow cover to the extent possible.

New ways of applying manure before planting or to growing crops should also be considered.

Reconsidering time windows and crops that can receive manure while avoiding manure application to high-risk fields at

times of high runoff risk can ultimately increase NUE. As a result, we can reduce environmental risk associated with manure application in cold climates. ■ The author is a research soil scientist for the Institute for Environmentally Integrated Dairy Management, USDAAgriculture Research Service.

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Look for opportunities While complex, modeling runoff nutrient losses, snowmelt, and other factors in cold climates has had recent success.

A surface runoff P model (SurPhos) developed by Peter Vadas (USDA-ARS) and collaborators is one model that aims to simulate the snowmelt process and how it affects soluble P loss. Using 108 site years of field data, Vadas and others showed that winter manure application had a 2.5 to 3.6-fold larger runoff P loss compared to nonwinter-applied manure.

Applying at least some manure on frozen or snow-covered fields is still a fairly typical practice, particularly for farms without adequate storage.

Researchers at USDA-ARS and Melissa Wilson at the University of Minnesota are investigating the effect of manure solids content on runoff N and P losses when manure is applied to a snowpack.

Results generally indicate that higher manure solids applied correspond to greater snowmelt runoff N and P concentrations and loading. However, the fraction of manure total P lost to snowmelt runoff was lower for semisolid manure compared to liquid manure, suggesting some possible influence of solids content on manure-P mobility in the snowpack.

Handling manure in cold climates is jofnm.com

F3 16-17 Q1 2020 Cold Climate.indd 3

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1/16/20 11:20 AM

A covered lagoon digester is put to use in Hanford, Calif.

Less methane by 2030 California agencies have programs in place to reduce methane emissions from livestock agriculture in the next decade.

by Geetika Joshi

F

armers and ranchers in California know that their Golden State is more than palm trees and beaches. It is the largest dairy producing state in the nation, and based on 2017 data, California housed 1.7 million cows and produced 39.8 billion pounds of milk on 1,331 dairies.

The overwhelming majority of our dairy cows — 91% — live in the Central Valley, while the remaining 9% reside in the northern coast and southern regions. These areas vary significantly in climate, water, and air quality, all of which play a role in on-farm animal and manure management methods. The cooler climates up north are well-suited to pasture-based operations, while

larger feedlot-style, flush-based systems prevail in the Central Valley.

The methane challenge California’s large number of cows contribute methane emissions, which result from the action of methanogenic bacteria that thrive in the cows’ guts.

Methane from livestock comes from two main sources: enteric fermentation, such as cow belching, and storage of manure in anaerobic (wet) conditions, such as ponds and lagoons.

Methane is a potent greenhouse gas (GHG), and its emissions are responsible for about 20% of the global warming now driving climate change.

In California, agriculture accounts

18 | Journal of Nutrient Management | February 2020

F3 18-19 Q1 2020 Methane.indd 2

for 8% of the total inventoried GHGs, and about 53%of that is from animal agriculture. Enteric fermentation contributes to 28% of our agricultural methane emissions, while 25% stems from manure storage.

State legislation passed in 2016, SB 1383, requires California’s dairy and livestock sector to reduce its methane emissions to 40% below 2013 levels by 2030. The statute requires the California Air Resources Board (CARB), in consultation with the California Department of Food and Agriculture (CDFA), to potentially adopt regulations beginning in 2024 to reduce methane from dairy and livestock manure management operations. SB 1383 also requires CARB jofnm.com

1/16/20 11:33 AM

to work with a broad range of stakeholders to identify and address challenges and barriers to the development of dairy methane emissions reduction projects.

While reducing enteric fermentation methane emissions remains a challenge that needs additional research and development, methods of manure management are well-researched and commercially available. One such method is establishment of anaerobic digesters to capture the methane produced from stored manure, which can then be used to generate renewable energy. There are also several nondigester technologies and practices that focus on eliminating wet storage conditions of manure to realize methane emissions reduction.

Funding for projects California currently offers voluntary financial incentives for implementing measurable methane reductions at dairy and livestock operations. These incentives are provided through two CDFA-administered programs: the Dairy Digester Research and Development Program (DDRDP) and the Alternative Manure Management Program (AMMP). These programs are funded through California Climate Investments, also known as the Cap-and-Trade program.

DDRDP was first developed and implemented in 2014-15 with an initial appropriation of $12 million. In its first year, the program funded six dairy digester projects in the Central Valley, where the captured methane was used to make renewable electricity. DDRDP to date has awarded approximately $181.6 million to implement 107 projects located on individual dairies throughout California. These projects generate renewable compressed natural gas (RCNG) fuel in addition to renewable electricity-generating projects. Thirteen dairy digester projects are now complete, and the remainder are in various phases of completion.

Funded dairy digester projects are located across seven counties in the Central Valley, and collectively they reduce approximately 2 million metric tons of carbon dioxide equivalents (MMTCO2e) annually, which equates to 420,000 cars jofnm.com

F3 18-19 Q1 2020 Methane.indd 3

This biogas cleanup and electricity generation equipment was installed in Bakersfield, Calif.

To make manure easier to handle, a solid separator was installed at a dairy farm in Escalon, Calif.

being taken off the road each year.

AMMP was first developed and implemented in 2016-17 in response to stakeholder interest in non-digester management practices. The need for large amounts of digester feedstock, a 50% financial match, proximity to natural gas pipelines, and ease of connection to existing electric grids are some of the key factors attributed to successful digester projects. Subsequently, smaller or more remotely located dairy operations needed a menu of additional options to participate in California’s methane reduction efforts.

AMMP incentivizes nondigester-based manure management practices. This includes conversion from water flush systems to dry scrape systems; solid separation followed by drying or composting of manure solids; compost-bedded pack barns; and increasing the amount of time animals spend on pasture.

AMMP has funded 106 projects totaling $61.9 million. Of these, 28 projects are complete, and the remainder are in various phases of completion. Funded projects are located across 12 counties and collectively reduce approximately 200,000 metric tons of CO2e annually.

This is equivalent to more than 42,000 cars being taken off the road each year.

In 2019, CDFA also funded three demonstration projects, totaling almost $2 million. The aim of these projects is to showcase new and innovative manure technologies as well as conduct outreach and educate dairy farmers.

poised to meet its target within the next decade for early and measurable methane reductions. In addition, many co-benefits exist that dairy producers can expect with a digester or alternative manure management practices.

For example, digesters can provide an important revenue stream from the sale of renewable energy, which also contributes to climate change adaptation.

Similar benefits may also be provided through production of compost.

Methods such as anaerobic digestion and drying of manure solids can potentially help reduce impacts to water quality, since these projects transform manure into a stabilized, easier-to-handle form.

The resulting dried manure compost can be moved and used as a soil amendment benefiting plant and soil health.

Most importantly, these voluntary initiatives provide California’s dairy families with the tools and capacity to engage in climate change efforts. Dairy agriculture is an important economic and food contributor, and it is also playing a key role in California’s efforts to lead the nation in practices to mitigate and adapt to climate change. ■

Opportunities exist With expectations for Cap-and-Trade funding to continue, California is

For more information on CDFA’s Dairy and Livestock Methane Reduction Programs, visit: DDRDP: bit.ly/JNM-ddrdp and AMMP: bit.ly/JNM-AMMP. Follow us on Twitter: @CDFAClimateNews.

The author is a senior environmental scientist with the California Department of Food and Agriculture, Office of Environmental Farming and Innovation.

February 2020 | Journal of Nutrient Management | 19

1/17/20 9:43 AM

Cover crops can be a bridge Capture more nutrients from manure by utilizing a cover crop.

by Brian Dougherty

A research project at the Northeast Research and Demonstration farm near Nashua, Iowa, has been investigating the potential to use cover crops to capture manure nutrients for the last four years.

One aspect of the study is evaluating cereal rye cover crop growth and nutrient uptake in a corn-soybean rotation receiving swine manure. The manure was injected at a rate of 150 pounds of nitrogen per acre (lbs. N/ac). Cover crop aboveground biomass samples were collected

Figure 1: Aboveground nutrient uptake by a cereal rye cover crop 140 120 100 80 60 40 20 0

N uptake

P uptake

K uptake

140 120 100 80 60 40 20 0

Figure 1. The figure shows aboveground nutrient uptake by a cereal rye cover crop directly over the manure injection band (blue bar), between the manure injection bands (gray bar), and before soybeans (tan bar — no manure applied).

20 | Journal of Nutrient Management | February 2020

F3 20-21 Q1 2020 Cover Crops.indd 2

adhere well to negatively charged clay particles, so it can easily leach downward through the soil profile.

The warmer soils are when manure is applied, the more rapidly the ammonium will convert to nitrate. This raises the likelihood of losing the N prior to crop uptake the following year.

For these reasons, cover crops can be especially beneficial in fields receiving fall-applied manure.

In the Nashua study, there were substantial differences in cover crop growth and nutrient uptake in the aboveground biomass directly over where manure had been injected (Figure 1, blue bars) com-

O ve rm an Be ure tw ba ee nd nm an ure ba nd No ma nu re O ve rm an Be ure tw ba ee nd nm an ure ba nd No ma nu re O ve rm an Be ure tw ba ee nd nm an ure ba nd No ma nu re

Capture nutrients with cover

in the spring just prior to termination and analyzed for nitrogen (N), phosphorus (P), and potassium (K) content.

Manure was typically applied in early to mid-October after soybean harvest, but before soils had cooled to 50°F. This type of manure application is common, yet highly susceptible to nitrogen loss.

Research has found that biological activity in the soil slows considerably when soils are 50°F or cooler.

Bacteria in the soil convert ammonium-N from manure to nitrate-N, which is readily available to crops. The nitrate molecule carries a negative charge and is very soluble in water. It does not

Aboveground nutrient uptake (lb/ac)

M

anure is an excellent source of valuable nutrients. However, it is susceptible to nutrient loss and impacts to water quality when applied long before a crop is present to take up the nutrients that manure provides.

Cover crops can help to bridge this gap. With proper management, cover crops and manure can work together to improve soil and reduce nutrient losses.

Manure adds nitrogen and other nutrients needed for soil microbial activity and crop growth. Cover crops can help capture and recycle those nutrients to the following crop and reduce the potential for nitrogen loss.

Soil microbial activity is enhanced with both manure and cover crops. This microbial activity has the potential to help with decomposition of cash crop and cover crop residue. Cover crops also help to improve soil structure and water infiltration.

jofnm.com

1/17/20 9:49 AM

pared to between the manure injection bands (gray bars). On average across the four-year study, the cover crop took up about 90 lbs. N/ac in plots receiving 150 lbs. N/ac from manure. The plots going to soybeans where no manure was applied took up about 60 lbs. N/ac.

These results suggest that the cover crop took up significant residual soil N following soybean and likely took up N from the manure itself. Cover crop N uptake in a previous eight-year study on these same plots was only 13 lbs./ac prior to soybeans and 21 lbs./ac prior to corn in a spring urea-ammonium nitrate (UAN) sidedress system with the same N application rate.

There was no significant difference in corn yield following the cereal rye cover crop in this study. The cover crop led to significantly lower nitrate-N concentrations in drainage water, thus helping to improve water quality. Plots with

cover crops also tend to have more water flowing through the drainage system, suggesting that more water is infiltrating rather than running off the surface. This research demonstrates the potential for substantial benefits when adding a cover crop to fields receiving liquid manure.

Start simple If you are new to using cover crops, it is a good idea to start with “easy” acres, such as corn silage or seed corn ground where you can get the cover crop established earlier. Starting with single-species cover crops like cereal rye or oats can simplify management.

Sampling both soil and manure will help determine where and how much to apply. Proper equipment setup and calibration will help to get manure and cover crop seed applied at a consistent rate and depth. Waiting until soil temperatures have cooled to below 50°F

to apply manure will help to reduce N loss. The Nashua study has also shown a substantial corn yield benefit (an additional 40 bu/ac) from this approach.

Monitor carbon to nitrogen (C:N) ratios in both manure and cover crops to help fine-tune management. Generally, the higher the C:N ratio, the longer it will take for a cover crop to break down and release nutrients back to the soil.

Treat the cover crop like a cash crop and manage manure like you would commercial fertilizer. They are both valuable resources worth the investment of your time. Attention to detail, planning, and flexibility will help make manure and cover crops a success on your farm. ■

The author is an ag engineering field specialist with Iowa State University Extension.

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to guide your application strategy Achieve nutrient management success the right way by focusing on the source, rate, timing, and placement of manure.

by Deanne Meyer

F

or farmers, local geography and climate determine the limiting nutrient for manure application. That being said, for much of the United States, phosphorus or nitrogen limit manure nutrient application.

A guide to manage manure nutrients is to use the four R’s: the right source, the right rate, the right time, and the right place. This also assumes there is a target crop yield and nutrient composition.

Why do people care about these four R’s? Efficient and sustainable livestock production relies on them. For many,

feed nutrients are imported to farms.

Nutrient management is an iterative process that allows you to more efficiently use residual feed nutrients for crop production.

Nutrient composition varies Let’s start with a review of the four R’s.

Right source. Manure solids, slurry, and liquids have different concentrations and ratios of organic and plant (ammoniacal) nitrogen. Organic nitrogen requires soil microbes to mineralize the nitrogen to ammonium. Much research focuses on better prediction of mineralization rates. Animal diet,

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housing and manure collection, storage, and treatment all influence the composition of manure that is applied.

For all animal facilities, manure from replacement animals will have a different nutrient composition than that of the mature animals. Testing manure sources provides farm specific nutrient composition to predict plant availability.

Identify sampling protocols for soil and manure. Your local or state Cooperative Extension Service or Natural Resources Conservation Service office may have established recommendations for sampling and plant nutrient application guidelines. jofnm.com

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Correct laboratory methods for analyses is essential for results to be useful.

Consult your water quality permitting agency to be sure your analyses are compliant. For us in California, wet chemistry is required and labs need to meet a specific certification.

The old adage “Test, don’t guess” is essential to use manure nutrients.

Consult with your nutrient management specialist to discuss concerns you may have related to using your various manure sources.

Right rate. Nutrient budgets provide a road map for application. The targeted crop nutrient removal is the starting point. Biological availability and losses are considered. Monitoring nutrient conservation is important to document nutrient stewardship.

Calculations require knowing the nutrient composition of manure and being able to deliver known amounts of manure to each field as uniformly as possible. It is important to be able to measure how much manure is applied.

It is also necessary to track when and where manure is applied.

How much nitrogen or phosphorus needs to be applied to meet your crop goal yields? Your water quality permit may establish target application rates.

For dairies in much of California, the rate of nitrogen application is targeted at 1.4 times the estimated crop nitrogen removal.

All nutrient applications are recorded.

Nutrients applied divided by nutrients removed are compared at harvest.

Annual reports to the regulatory agency include a crop by field summary of actual practices. Targeting the right amount of plant-available nitrogen may be equally important in your watershed.

In other parts of the country, phosphorus is the limiting nutrient. Phosphorus application rates are based on anticipated available soil phosphorus. A Bray, Mehlich, or Olsen test is conducted, depending on soil type, and application recommendations are based on test results. Your local Cooperative Extension Service or Natural Resources Conservation Service office should be jofnm.com

F3 22-23 Q1 2020 4Rs.indd 3

able identify which test best suits your soil type.

Where it belongs Right time. Timing manure nutrient applications with plant nutrient needs helps utilize nutrients efficiently. Solid and slurry manure applications usually are limited by local cultivation practices.

Use manure testing to determine the specific nutrient composition of the material that will be applied to the field.

Manure spreaders and slurry tanks transfer manure from storage to fields. This often occurs before crops are planted. Liquid manure applications can be water run in irrigation systems. This allows applications once crops are planted.

Flood, pivot, or drip line irrigation systems may incorporate diluted liquid manures. Adequate filtering of particles is essential to minimize clogging of these systems. In some pivot systems, paired nozzles allow for delivery of liquid manure and rinsing of plants after liquid manure application.

Weather is another key factor. Timing of application requires the ability to get into fields as well as the ability of manure to stay where it is applied.

Frozen or saturated soils don’t lend themselves to optimum manure management. You’ll want to be sure you know your permit restrictions if you live in a state that prohibits manure application on frozen soil or if you have restrictions on application to saturated soils.

California doesn’t have frozen soils where dairies reside. However, it can have intense rains in winter, leaving

some fields inundated with water.

Application of manure to these fields when saturated is not allowed.

Right place. Different cultivation practices are used for permanent crops, pastures, and forage production. Nutrient application in orchards targets areas where tree or vine roots reach and band application of nutrients occurs.

Pasture or alfalfa fields provide longterm ground cover. Surface application with minimal incorporation occurs on these fields.

Annual crops often require more cultivation. Application with direct (shank injection) or partial (irrigation) incorporation of nutrients can be done. Surface application with direct incorporation (tillage) is also possible. The objective is to place nutrients near plant roots and keep them there as long as possible for plants to use.

Soil type and water holding capacity are important factors associated with keeping nutrients near plant roots. Soil management remains key in a nutrient management strategy.

Nutrient budgets take into consideration local conditions to identify targeted nutrient applications. Matching manure nutrients to crop nutrient needs helps use nutrients more efficiently. It also improves your bottom line to use nutrients you have already imported as feed and minimize the need for importing other nutrients to the farm.

If your animal operation does not have sufficient crop production capacity for the manure generated, you may have already identified off-site prospects for manure. On-farm practices to make nutrients more dense for export may be in place. No doubt, you are already paying close attention to new, potential on-farm manure utilization technologies. These technologies, paired with the four R’s, can help maximize delivery to your crops. ■ The author is a livestock waste management specialist with the University of California, Davis Department of Animal Science.

February 2020 | Journal of Nutrient Management | 23

1/16/20 11:40 AM

FARMING FOR A BETTER

FUTURE Rob Stout and his stepson, Alex Zimmerman, raise hogs and grow corn and soybeans at their Washington, Iowa farm.

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jofnm.com

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Farmers often serve as the ultimate stewards of the land, and hog producer Rob Stout would certainly fit that description.

Abby Bauer

E

t a young age, Rob Stout discovered his passion for animals and decided to become a farmer. Early in his career, he also became passionate about protecting the land for himself and for generations to come.

Stout’s agricultural roots run deep. He is a ninth-generation farmer and is the fifth generation to grow crops and raise hogs in Iowa. At one time, their family raised beef cattle, too, but today, Stout and his stepson, Alex Zimmermann, focus on feeding out hogs on their Washington, Iowa, farm. At any one time they have 3,600 feeder pigs in their barns, finishing out 9,000 hogs per year.

After graduating from Iowa State University in 1978 with an agricultural degree, Stout returned home to farm with his dad. About 10 years later, Stout began renting the land that now serves as the main location for the current farm. Back then, they used the facilities on that property to calve out beef cows, but when lightning struck and burned down that barn in 1997, they decided to sell the beef cattle.

A few years prior to that, in the early 1990s, Stout invested in a sow cooperative with nine other owners. They started with 1,200 sows. The cooperative is 8 miles north of Stout’s farm, with a nursery facility located at another site.

Twenty-five years later, there are six owners of the cooperative with 2,400 sows. They meet monthly to make decisions about animal care, breeding, jofnm.com

F3 24-26 Q1 2020 Better Future.indd 25

and facilities.

Stout receives pigs from the cooperative when they are 9 or 10 weeks old. They are fed for around 18 weeks, and once finished, they are sold on the open market.

The pigs are housed 25 to 34 per pen, and there are about 600 pigs per barn.

The barns are mechanically ventilated, and sprinklers turn on at 84°F to cool the animals in hot weather.

Stout works with a nutritionist to formulate 22 different diets — 11 for barrows and 11 for gilts. The females receive a higher level of protein in their rations. The automatic feeders are run on sensors, delivering small amounts of fresh feed multiple times per day.

Stout carefully observes water consumption and records the daily water intake for each barn. He uses these numbers to monitor animal health, noting that water consumption typically goes down a day before pigs become sick, indicating a problem.

Once a group of pigs is sold, the barn is pressure washed and sanitized before the next group of pigs move in.

Even though Stout has farmed all his life, his philosophy is to seek out opportunities for continuous learning. “This business changes so fast, you have to

keep up or you’re falling behind,” the thoughtful farmer said.

For better soil health

When it comes to the land on their farm, Stout said, “I believe in soil health,” and he has certainly taken steps over the years to support that statement.

In addition to the hog operation, Stout and Zimmerman also have 1,100 acres used to grow corn and soybeans. They have been no-tilling the fields since 1983, after Stout attended some no-till tours put on by their extension director and encouraged his dad to give it a try.

Abby Bauer

G

by Abby Bauer | Managing Editor

The bioreactor on Stout’s farm was one of the first to be installed in the area. He tests the water monthly for nitrate levels.

“When I talked to my dad about it, he wasn’t so sure of the idea. He said, ‘You buy a planter, and we’ll give it a go,’” Stout explained. “And we never looked back.”

Over time, Stout has learned a lot about successful no-till. For example, he said it’s important to get residue out of the rows with row cleaners to

February 2020 | Journal of Nutrient Management | 25

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prepare the seedbed. “The art of no-till is an evolving process,” he said. “I try to keep an open mind and attend a lot of continuing education.”

Stout commented that their view of manure has also changed over the years. “Manure was once considered a waste product, but then we became more aware of the value.” Complementing the no-till, they started injecting manure in 1996. Older low-disturbance injectors left the ground bumpy, he said, but the last two they have owned allow him to plant right after manure injection.

By injecting the manure, the odor is really minimized, Stout said. Still striving to be a good neighbor, he will avoid spreading manure on holidays and when the wind is blowing directly at someone else’s property.

To make the best use of the nutrients, Stout carefully tests his soils every four years in 2.5 acre grids. He uses that data to determine fertilizer needs, and manure is part of that package.

Using manure saves Stout thousands of dollars in fertilizer costs and improves soil health.

Manure is stored in pits underneath their hog barns, and they try to get them completely emptied in the fall.

Swine manure contains a lot of water, so it is less concentrated than some other manure forms. Stout tests his manure every fall, and it typically contains about 55 pounds of nitrogen (N), 22 pounds of phosphorus (P), and 35 pounds of potassium (K) per 1,000 gallons.

Stout complements the manure with variable-rate applications of commercial fertilizer, which is done by a hired applicator. Stout does this to fine-tune N, P, and K application.

He also delivers nutrients to the field several times per year, through manure application, fertilizer applied with the planter, and by sidedressing growing plants, so that crops don’t get a full dose all at once.

“Spreading it out through the year is environmentally better,” he explained.

They also do the stalk nitrate test on growing corn to monitor nitrogen levels. “We are trying to do the right thing to make sure there isn’t too much

Low disturbance injectors make a groove for the manure, then kick some soil over it. Stout and Zimmerman apply all of their own manure, about 1 million gallons each fall. nitrogen on a field,” he said. “I’m always open to improvements.”

Watching the water

Careful application means more nutrients stay on the fields where they belong.

For the past eight years, Stout has been testing the water and working diligently to reduce nitrates in their area.

He belongs to the West Fort Crooked Creek Watershed Group, and it was through that organization that he initially received funds to do water nitrate testing. When he started testing, nitrates were at 14 to 18 parts per million (ppm).

He began planting cover crops to reduce nitrates and phosphorus in water. He said he started small but plants covers on all his acres now.

He also installed a subsurface bioreactor on a tiled field in 2014. The bioreactor intercepts drainage from about 70 acres.

As water passes through the bioreactor, denitrifying bacteria in the wood chips convert nitrate into dinitrogen gas.

Stout tests the water at the inlet and outlet of the bioreactor monthly, and over the past five years, he has seen a nitrate reduction of 70 percent. Aside from one really rainy month, their nitrate levels now stay below 10 ppm.

The bioreactor is 30 feet wide, 90 feet long, and 6 feet deep. It contains 4 feet of wood chips, with 2 feet of dirt over that. Pollinator flowers are planted on top of it. In all, the bioreactor takes up about one-tenth of an acre.

Even with cost sharing through the watershed group, the bioreactor was a significant financial investment, Stout explained. Still, he was pleased they installed it as he felt they were “doing

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F3 24-26 Q1 2020 Better Future.indd 26

the right thing.”

Stout’s bioreactor was the first one installed in their area. So far, it is working well, and he hopes it lasts the 20 years it is expected to before the wood chips need to be replaced.

To further prevent runoff, Stout has also planted some native grass buffer strips to slow the flow of rainwater, snowmelt, and nutrients. “We do what we can to keep nutrients on the farm,” he said.

Open to improvements Solar panels are another environmentally friendly aspect of the Stout farm.

The first rooftop solar panels were placed six years ago, with more added over time. Stout works with Alliant Energy on a net metering system, and the panels cover the electrical needs of the pig barns year-round.

Again, this was an expensive project to complete, with an anticipated payback period of six years. However, Stout was happy to do it and said, “Environmentally, it is a good thing to do.”

Much of what Stout does is to leave the land in better shape for those who farm after him, and he feels many other farmers are doing the same.

“There are a lot more regulations now than when I started farming,” he said. “But things that are happening are good. We are taking better care of our hogs. We are taking better care of our manure. We are all doing better at taking care of the environment.”

Stout plans to continue raising hogs and crops with his stepson. Maybe one day, one of his young grandsons will follow in his footsteps and farm the land he has worked so hard to preserve. ■ jofnm.com

1/16/20 11:45 AM

POULTRY SYMPOSIUM PRODUCTION & PROCESSING The poultry symposium hosted by The Poultry Federation of Arkansas, Missouri and Oklahoma will take place on April 15-16, 2020 at the John Q Hammons Convention Center in Rogers, AR Live production and processing personnel as well as suppliers who support live production and processing of turkeys, breeders and broilers are encouraged to register and attend. Agenda includes a general session with five breakout sessions focused on: breeder, broiler, hatchery, turkey and processing.

The poultry symposium vendor tradeshow runs for two days and is a prime outlet for allied industry members to showcase their products and/or services to attendees. Attendees of the Symposium will include top level decision makers in live production and processing.

REGISTRATION FEES: $100 TPF Member ¡ $125 Non Member Learn more and get registered at www.thepoultryfederation.com

Poultry litter brings long-term benefits The use of poultry manure as a fertilizer has been found to improve crop yields and soil health over time.

by Natasha Hoover, Ji Yeow Law, Leigh Ann Long, Ramesh Kanwar, and Michelle Soupir

A closer look at the nutrients After 20 years, Bray-P analysis indicated average phosphorus (P) levels of 317 ppm (parts per million) in the topsoil of the plots treated with poultry manure. Elevated phosphorus concentrations in topsoil pose a risk for contributing phosphorus to surface waters during storms.

When soils carry high P levels, conservation practices should be used to reduce erosion. Producers can also con-

Figure 1: Corn-soybean phase (1998 to 2009)

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F2 28-29 Q1 2020 Polultry.indd 2

timeters (cm) (48 inches) and analyzed in five increments: 1. 0 to 6 inches 2. 6 to 12 inches 3. 12 to 24 inches 4. 24 to 36 inches 5. 36 to 48 inches

health in the manured plots compared and plots fertilized with UAN. Such benefits included more total soil carbon, particulate organic matter, and improved soil structure.

Greater amounts of soil organic matter enhance soil cation exchange capacity, which provides greater long-term soil fertility. Particulate organic matter is partially decomposed plant material that stabilizes soil particles by binding them together into aggregates, which minimizes erosion, improves root penetration, reduces bulk density, and enhances water infiltration and soil water-holding capacity. It is also a source of organic nitrogen (N), which can be slowly released for improved soil fertility.

Deep-soil core samples were collected in the fall of 2017 to a depth of 120 cen-

Nitrate-N, mg L-1

long-term study of the impacts of continued poultry manure application on soil health and nutrients, water quality, and crop yield response with economic analysis was completed in the fall of 2017. The 20-year study was initiated in 1998, with a 12-year corn-soybean phase (CS Phase) from 1998 to 2009, and an eight-year continuous corn phase (CC Phase) from 2010 to 2017.

Poultry manure was applied to plots at a low or high rate during each phase; a crop-recommended rate and a double-application rate during the CS Phase, and a crop-recommended and half-application rate during the CC Phase. Urea ammonium nitrate (UAN) was applied at the crop rotation-recommended rates of 150 pounds per acre during the CS Phase and 200 pounds per acre during the CC Phase.

The goal of the study was to provide a long-term assessment of the environmental and economic affects of poultry manure application in tile-drained agricultural systems of the Upper Midwest.

The results provide a comprehensive overview of poultry manure’s impact on agroecosystems, supporting on-farm decision making and watershed level nutrient management strategies.

After 20 years of manure application, there were measurable improvements in multiple parameters of soil

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■ High poultry manure

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Post-application

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Late season

Stage of field management or crop growth

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PO 4 -P concentrations was not detected over the years.

sider applying poultry manure based on the P needs of the crop instead of the N requirements.

While manure application had the greatest impact on soil phosphorus, nitrate (NO3-N) levels were most notable in the tile drainage. Comparing the impacts on drainage nutrients of poultry manure (PM) and UAN applied at the same N rates throughout the study (CS Phase: Low PM versus UAN; CC Phase: High PM versus UAN), we see that UAN application resulted in higher average NO3-N concentrations under all conditions.

For this article, we separated the average drainage results from our study into four stages of field management or crop growth: before manure and UAN application; postapplication through the early growing season; the rapid growing season; and late season after the crops have reached maturity (see figure). The late-season CC Phase results were a single sample date.

As expected, the highest NO3-N concentrations were observed post-application, with generally lower concentrations during the growing season.

Poultry manure applied at the crop recommended rate (PM-CS, PM-CC) did not result in elevated drainage NO3-N concentrations compared to UAN at the same application rate.

Tile drainage orthophosphate (PO 4 P) concentrations were highest in the poultry manure-treated plots, but they remained relatively low throughout the study period. An increase in

Crop yields were positive Throughout the 20-year project, consistently positive yield results were measured with manure application.

During the CS Phase, corn yields were higher with both the low and high poultry manure application rates compared to UAN. Even though fertilizer was not applied to the soybean crops during this same time period, the soybean yields were also higher in the poultry manure plots.

The same trend was observed during the CC Phase, with higher corn yields measured in both the low and high applied poultry manure plots. Again, the low PM application during the CC Phase was half the UAN application rate. It should be noted that the UAN plots did not receive a regular maintenance application of phosphorus and potassium, likely inhibiting crop growth.

A viable option A Techno-Economic Analysis (TEA) was conducted to compare the potential profitability of poultry manure with UAN fertilization individually for the CS Phase and CC Phase of the study.

One method for evaluating profitability is comparing the revenue per dollar of input cost (RPI).

The input costs included estimated production costs and the manure or UAN costs based on this study’s application rates. Total revenue was deter-

mined using the average crop yields and average annual crop prices for both phases of this study.

A difference in RPI was not observed between the poultry manure and UAN treatments with a corn-soybean rotation. A higher RPI was observed with poultry manure treatment during the CC Phase, indicating that poultry manure can be a profitable option for continuous corn production.

This comprehensive 20-year assessment of the environmental impacts of poultry manure produced promising results for producers. Greater yield was typically observed from field plots amended with poultry manure; yet, NO3-N concentrations in drainage were generally lower than the UAN-treated plots.

PO4 -P concentrations in drainage water were well below the EPA-recommended total phosphorus (TP) limit of 0.05 milligrams P/L for streams discharging into lakes. Although phosphorus levels rose significantly in the topsoil of the poultry manure-treated plots, we did not measure an increase in PO4 -P concentrations in drainage water over the study period.

Particulate organic matter levels in plots amended with poultry manure were greater than plots amended with UAN, indicating positive soil health benefits associated with long-term poultry manure application. From an economic perspective, both the corn-soybean rotation and continuous corn generated equal or greater average revenue per dollar of input than UAN treatments. ■

Nitrate-N, mg L-1

Figure 2: Corn-soybean phase (2010 to 2017) ■ Low poultry manure

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■ High poultry manure

■ UAN

30 20 10 0

Pre-application

Post-application

Growing season

Stage of field management or crop growth

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Late season* *Limited samples

The authors are faculty and staff members in the department of agriculture and bioengineering at Iowa State University. Pictured are (L to R): Michelle Soupir, Ji Yeow Law, Leigh Ann Long, Natasha Hoover, and Ramesh Kanwar.

February 2020 | Journal of Nutrient Management | 29

1/16/20 10:38 AM

Tracking down the nitrate source

by Michael Sklash and Fatemeh Vakili

common reaction to the word “isotopes” is that they are nasty fallout from atomic bombs.

This article explains how isotopes (even some related to atomic-bomb fallout) have helped to change our understanding of where nitrate in streams and groundwater originated.

Hint: It may not be what you think.

The building blocks Remember how we used to think of atoms in high school? There are three things to remember. First, an atom is the smallest bit of an element, like hydrogen (H), that retains the chemical and physical properties of that element.

Second, atoms are made up of a central nucleus of protons (positively charged objects) and sometimes neutrons (neutrally charged objects) surrounded by orbiting electrons (negatively charged objects).

Third, protons and neutrons have mass (weight). Electrons do not.

Next, an atom can have several different versions, or “isotopes,” that differ only by the number of neutrons in the nucleus. For example, all H atoms have one proton and one electron. Hydrogen has three isotopes: “protium” (1H) has one proton and one electron, “deuterium” (2H) has one proton, one electron, and one neutron, and “tritium” (3H) has one proton, one electron, and two neutrons.

Hydrogen isotopes are denoted by the superscript next to the “H.” The superscript is the atomic mass (protons plus neutrons). Heavier isotopes (those with higher atomic mass) behave differently

than lighter isotopes during physical processes like evaporation of water.

Determine nitrate sources How have isotopes changed our understanding of where nitrate in streams and groundwater originates?

First, scientists used hydrogen and oxygen isotopes in water molecules to determine the relative age of stream water during storms.

Second, scientists utilized tritium in water molecules to determine the age of groundwater.

Third, scientists used isotopes of nitrate in groundwater to determine whether the nitrate originated from commercial fertilizer or manure.

Why should you care about the age of the water in your stream?

It is commonly understood that, with few exceptions, when a stream is at low flow during drier conditions (“base flow”), the water in the stream comes from groundwater seepage. Up until the 1970s, it was generally thought that when there was a storm in a watershed and flow in the stream quickly increased, the extra flow was water from that specific rainfall event (known as overland runoff).

This thinking started to change in the 1960s and 1970s. Scientists began using hydrogen and oxygen isotopes in water molecules as watershed-wide natural tracer experiments to determine where the water in streams originated during storms. This included snowmelt events, too, but we will focus on storm events for this article.

Early isotopic studies started with the

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assumption that the water in a flooding stream is a mixture of rainwater and groundwater. Many studies used the ratio of oxygen isotopes (18O/16O) as the “isotopic signature” in watershed-wide natural-tracer experiments because the isotopic signature of a rainfall event and groundwater can be very different. The percentage of rainwater and groundwater in the streamwater is then calculated based on the isotopic signatures of the rain and groundwater and the resultant oxygen isotope ratios in the flooding stream.

One of the earlier studies by Michael Sklash and Robert Farvolden in 1979 used oxygen isotope ratios to determine the percentage of rain and groundwater in storm runoff in a small, sandy agricultural watershed. Contrary to intuition and most textbooks, they determined that groundwater supplied at least 80 percent of peak flow during some large storms.

Dozens of studies have followed with similar results depending on soil types, antecedent moisture conditions, slope, and other factors. The higher water flows in streams following storm events contains a large proportion of old, stored groundwater that was already in the catchment prior to the storm.

What does this mean for the stream on, or near, your farm?

If someone samples your stream during base flow and tests for nitrate or other chemicals, the data may not reflect your current agricultural practices.

Similarly, if someone samples your stream during a storm runoff event and jofnm.com

1/17/20 9:50 AM

tests for nitrate or other chemicals, the data likely are greatly influenced by past agricultural practices.

How old is your water?

Although groundwater can be very responsive and contribute to storm runoff, in general, groundwater moves very slowly. The groundwater beneath your land could be tens, hundreds, or thousands of years old. Tritium (3H) can be used as a watershed-wide tracer to determine the age of your groundwater.

The concentration of 3H in groundwater is the result of four main factors.

First, tritium is a naturally occurring isotope in precipitation and had a concentration of about 10 tritium units (TU, which means one tritium atom in 1,018 protium atoms) or less until the earlier 1950s. Second, the tritium concentration in groundwater is the result of a mixture of many years of precipitation.

Third, tritium concentrations rose to thousands of TU during the Cold War atmospheric testing of nuclear bombs; this was called “bomb tritium.” The bomb tritium input peaked in 1963 and diminished after the USA and USSR signed an atmospheric test ban treaty.

Finally, since tritium is radiogenic, the amount of 3H in precipitation has gradually decreased since 1963.

As a result of this tritium input history and behavior, we know: 1. Groundwater that was recharged from precipitation before 1953 will now have no detectable tritium.

2. Groundwater that was recharged from precipitation in 1963 will now have less than 100 TU of tritium.

3. Current tritium concentrations in rainfall in central North America are again at about 10 TU. What does this mean for groundwater on your property?

1. If there are elevated concentrations of nitrate in your groundwater and your groundwater has no detectable tritium, that nitrate probably came from before 1953 (“legacy nitrate”).

2. If there are elevated concentrations of nitrate in your groundwater and that groundwater has about 60 TU, that nitrate is “legacy nitrate.”

3. If there are elevated concentrations of nitrate in your groundwater and that jofnm.com

F2 30-31 Q1 2020 Nitrate.indd 3

groundwater has about 10 TU, that nitrate may be yours but could also be “legacy nitrate.”

Scientists can use the ratios of two nitrogen isotopes (15N/14N) and oxygen isotopes (18O/16O) in dissolved nitrate (NO3) in groundwater and surface water to determine the source, or sources, of the nitrate.

Commercial chemical fertilizer and manure have different nitrogen and oxygen isotope signatures. Margaret Townsend and others (2001) provide a simple bar graph that indicates groundwater impacted by commercial fertilizer has a relative 15N/14N concentration range of about -5 to +10 per-mille, while groundwater impacted by manure has a relative 15N/14N of +10 to +25 permille. Graham Fogg and others (2005) evaluated many 15N investigations and demonstrated similar isotopic differences between farm fields that had applied animal waste versus chemical fertilizer. Some scientific papers report slightly different limits.

What does this mean to the farmer?

Groundwater flow and groundwater chemistry are frequently more complicated than regulators consider them to be. If anyone finds nitrate (or any other chemical) in your groundwater or stream water, do not automatically assume that the nitrate comes from your agricultural practices.

If there are different potential sources of nitrate on or around your property, using isotope signatures is a useful tool for determining whether the nitrate comes from current or past agricultural activities. ■

Sklash is a senior hydrogeologist for Dragun Corporation.

Vakili is a hydrogeologist for Dragun Corporation.

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February 2020 | Journal of Nutrient Management | 31

1/16/20 10:39 AM

ON THE MOVE

RELATIONSHIPS AND HOPE FUEL THE NEW YEAR By working together, we can get through the tough times.

by Jesse Dvorachek

s I sit in my office amid piles of work I need to catch up on from the long, extended manure hauling season, I have flashbacks to the “exciting” fall we all had . . . broken safeties on rippers, more blown hoses than a guy would care to remember, and tying chains and straps together to get equipment pulled out of muddy fields. Those were just some of our issues, but I know our challenges were no different than most applicators in the Midwest.

I then had a warm, positive feeling come over me as I thought of all the phone calls I shared with other professional nutrient applicators. For a while in October and November, we were sharing our daily miseries, and the big question was, “How are we going to get this all done?”

For the most part, we are going to get it all done. We are going to get our customers through and have our best year yet in the worst conditions Mother Nature has ever thrown at us!

Working as a team I talked with many applicators, most of whom I am lucky to call friends, on the daily struggles they were going through. I would try to help and leave them with a positive note and the hope that the rest of the day, week, and season were going to be better. It had to get better. We, as a custom applicator group, are extremely resilient.

As the season progressed, I found we were talking more and more about how

we could assist one another by helping each other’s customers and sharing equipment and resources as much as possible. I am very proud to be in an industry where when things get tough, we can band together and share ideas, equipment, and

On particularly rough days when I’m sure I can’t endure, I like to remind myself that my track record for getting through the bad days so far is 100% . . . and that’s pretty good.

any other resources we have available to help each other get the job done.

In a year when farmers were already struggling to get crops off, customer relations were also a sensitive aspect of the business. They needed to help us manage how we were going to get manure out of storage and do it as best we could with the conditions we were handed.

We pump about 250 million gallons a year, running two transfer crews and one directing crew. Our company was moving anywhere there was ground that was even marginally ready to go. And that often brought up tough conversations when a customer was expecting you to be there until the pit was empty, and instead saw their applicator leaving them with a half-full pit in mid-November.

Normally, that is the time of year we are returning to empty them out one last

32 | Journal of Nutrient Management | February 2020

F2 32 Q1 2020 On the move.indd 2

time before deer hunting or Thanksgiving. But this year was anything but normal. Getting to a place of understanding — and the hope that better weather was coming — was the only thing we had on our side, and hope was a big part of it.

Author unknown

Bad days won’t stop us As the calendar flipped to 2020, I got a text from a customer who wanted to get a little more out of their manure storage. So, we went into the new year with a super early start and more of the same conditions. But, a new year means a new start.

As I leave you with this first column, I’d like to share a saying my lender sent me that I reflect upon often: “On particularly rough days when I’m sure I can’t endure, I like to remind myself that my track record for getting through the bad days so far is 100% . . . and that’s pretty good.”

Author unknown

The author owns Dvorachek Farm and Industry LLC, a custom manure application company in Brillion, Wis.

jofnm.com

1/17/20 9:45 AM

FRESH PAINT KUHN INTRODUCES NEW PUSH BOX SPREADER The new Kuhn Knight HP 160 hydraulic push box spreader features the proven ProPush design in a higher capacity, commercial duty package. The HP 160 with VertiSpread vertical beaters is designed to haul and spread solid materials from dairies and feedlots, including gutter manure, yard scrapings, bedding pack, and feedlot manure. The hydraulic push-type design means no apron chains, fewer moving parts, and dependable service life.

The HP 160 joins the 2044 and 2054 ProPush hydraulic push box spreader family, but features new upgrades and a greater heaped capacity of 600 cubic feet. The all-steel welded frame on the HP 160 provides a solid foundation for the spreader’s sides and floor. The solid weld-in tongue is cross-braced for

strength and rigidity, while the updated pusher design has increased the clearance between the tractor and implement for greater maneuverability.

VertiSpread vertical beaters equipped on the Kuhn Knight HP 160 provide customers with a uniform 25- to 30-foot

spread pattern with excellent material breakup. Polylaminate floor and sides minimize friction and deliver exceptional machine clean out. For precise monitoring and application tracking, an optional scale system is available. For more information, visit www.KuhnNorthAmerica.com.

TWO SPREADERS ADDED BY OXBO Oxbo International introduced the latest members of their nutrient management system, the 4103 and 5105 LNMS spreaders.

The three-wheeled 4103 offers a 4,200-gallon tank, and the five-wheeled 5105 has a 6,600-gallon capacity. Both feature 6-inch connections with quick couplers and 10-inch jofnm.com

F2 33 Q1 2020 Fresh Paint.indd 2

galvanized pipework to maximize their capabilities. The premium Vogelsang Rotacut cutter offers 2,600 gallons per minute capacity and is mounted on the side with a large door for easier clean out.

The spreaders are equipped with CAT IV three-point hitches to connect to a wide

variety of injectors and are capable of being used in drag hose operations. Both chassis have powered front wheels for optimal agility and traction, and the 5105 has steerable rear axles. The spreaders are powered by fuel-efficient Scania Tier 4F engines. For more information, visit www.oxbocorp.com.

February 2020 | Journal of Nutrient Management | 33

1/16/20 10:43 AM

PLACES TO BE Cattle Industry Convention & NCBA Trade Show February 5 to 7, 2020 Henry B. Gonzalez Convention Center San Antonio, Texas Details: convention.ncba.org Midwest Cover Crops Council 2020 Annual Conference February 11 and 12, 2020 KCI Expo Center Kansas City, Mo. Details: http://mccc.msu.edu/about/ meetings

Cutting edge, research-based information for: • Livestock producers • Custom operators • Commercial hay growers • Forage consultants, and • Educators

World Ag Expo February 11 to 13, 2020 International Agri-Center Tulare, Calif.

Details: worldagexpo.com Midwest Poultry Federation Convention March 17 to 19, 2020 Minneapolis Convention Center Minneapolis, Minn.

Details: http://midwestpoultry.com Central Plains Dairy Expo March 24 to 26, 2020 Sanford Premier Center Complex Sioux Falls, S.D. Details: www.centralplainsdairy.com California Dairy Sustainability Summit March 25 and 26, 2020 CalExpo Sacramento, Calif.

Details: www.cadairysummit.com 2020 Pork Management Conference April 20 to 23, 2020 Hilton Sandestin Beach Golf Resort and Spa Destin, Fla. Details: www.pork.org/events/ pork-management-conference World Pork Expo June 3 to 5, 2020 Iowa State Fairgrounds Des Moines, Iowa Details: www.worldpork.org 34 | Journal of Nutrient Management | February 2020

F2 34 Q1 2020 Places To Be.indd 34

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