IMMAG Updates

January 2017

Welcome to the monthly update for the Iowa Manure Management Action Group (IMMAG) Web site. This update is provided as a service to inform you about changes made to the IMMAG Web Page or items of interest dealing with manure management and air quality from animal feeding operations. If you wish to subscribe to this mailing please click here. You may also view this update with direct links on the CURRENT NEWS site on IMMAG.

Follow iowamanure on Twitter Follow the Iowa Manure Management Action Group on Twitter at @iowamanure.


Biosecurity Tips

Regardless of whether or not there is a disease outbreak, biosecurity procedures should be followed at all times to prevent the potential for the spread of disease. Our top five biosecurity best practices are:

  • Communicate with the manure handler and discuss the biosecurity plan. Ask about the history of the sites where the pumping was previously, plan the entrance and exit to the site, and determine which routes will be used to transport the manure to fields.
  • Identify the Perimeter Buffer Area, which serves as the outer boundary around the building(s) to reduce the potential for contamination around the building. Only vehicles and equipment which have been properly cleaned and disinfected should cross the perimeter buffer area.
  • Establish and maintain a Line of Separation (LOS), which separates the area used by the manure handling crew and the area used by farm staff.
  • Wear clean clothes and boots at every farm. Dispose of or contain contaminated clothing and clean and disinfect re-usable gear before moving to the next site.
  • Clean and disinfect your equipment and vehicles by removing all visible debris before disinfecting equipment before moving to the next site.

Recent AFO Rule Changes

In December, changes regarding insufficient storage were modified. New rules will accept insufficient storage capacity as a reason for emergency application during the snow covered and frozen ground application periods. This is applicable to facilities that have not constructed manure storage structures after May 26, 2009. If structures were constructed after May 26, 2009, these facilities must retain all manure between December 21 to April 1, unless proper application can occur and the ground is not frozen or snow covered.

Figure 1. Quantifying odor using the olfactometer.Olfactometer - What’s that smell?

By Ashley Denning (ASABE Undergraduate Student)
It is not uncommon to be walking in a store and smell one person who put on too much perfume or cologne. It may smell good in a small dose, but the intensity can change your perception and make your nose hurt, but how do you quantify the intensity of a smell?  One way is with an olfactometer. In this test, a panelist smells three samples, one of which contains the odor and two blanks, and identifies which of the samples contains the odor. This is repeated with the odor sample diluted at various ratios until the panelist can no longer correctly identify which sample has the odor. This result may differ person-to-person, depending on age, gender, and other factors, but the concept of measuring smell intensity is still the same.

Similarly, odor continues to be a concern for animal operations, especially swine farms. The odor from these farms is due to a variety of odorants, typically from gases emitted from the manure. Researchers suggest the actual smell is a result of several hundred different gases. Some of the generated gases, such as carbon dioxide and methane, are odorless. However, others are potent smelling, like ammonia and hydrogen sulfide. In addition to these four common gases, a suite of partially degraded carbon, nitrogen, and sulfur compounds, like indoles, skatoles, cresols, and volatile fatty acids, are produced that provide each farm a characteristic odor that is unique based on the animal type, management, and microbial consortia that develops in the pit.

As part of ongoing research conducted at Iowa State University, studies are being done on different techniques to reduce farm odor. Air samples are collected from different farms, brought back to the laboratory and the odor intensities are quantified using an olfactometer.  Initial results have been promising on a wet scrubber. The next time you get a breath of farm fresh air, know there are scientists working hard on the odor issue.

Figure 2. Manure injection examples.Manure Injections - Science of sizing

Injection or immediate incorporation has become a common practice, used by the majority of farms in Iowa for manure application. Getting the manure in contact with the soil helps reduce odor from land application and conserve ammonia, by keeping it from volatilizing, but what is the science behind this? Find out more in this month’s Manure Scoop.

Farmland Drainage Workshop March 3

A Farmland Drainage Workshop will be held from 8:30 a.m.-4:15 p.m. on March 3 at the Iowa Bioprocess Training Center in Eddyville, Iowa. The workshop will provide information essential for designing and planning a new drainage system or retrofitting an existing system. The economic and long-term benefits of tiling will be covered, as will a discussion on environmental impacts from drainage. New technology that may be useful in minimizing negative environmental impacts will also be covered.  To get more details including registration information, please visit

Manure Applicator Training Continues

Don’t miss out on the upcoming confinement and dry manure certification workshops, which run through the end of February. If you are unable attend one of the scheduled workshops, you can contact your local county extension office about reshowing these programs. There is no charge for attending the workshops or viewing the video on the scheduled reshow date and time. However, applicators requesting to view the training materials at non-scheduled times will be charged a fee. Additionally, the DNR also offers E-Learning for both Commercial and Confinement Applicators.



February 17, 2017 - The Livestock and Poultry Environmental Learning Center will be hosting a webinar at 1:30 pm on Avian Influenza Mortality Management Options, Composting Procedures and Lessons Learned. More information about this webinar and how to participate can be found here.

Additionally, the Livestock and Poultry Environmental Learning Center has partnered with the Manure and Soil Health team to bring you four great roundtables to improve our understanding of: current knowledge, critical and emerging issues for which there are knowledge gaps, and information needs of farmers and their advisors.

Manure and Soil Heath Testing - February 9, 2017

Manure and Soil Biology - February 16, 2017

Manure and Soil Erosion, Runoff, and Losses - February 23, 2017

Manure and Cover Crops - March 9, 2017

All roundtables will be held at 11 central, Noon eastern. Register at: or

How Do I Participate?

  • ANY TIME between now and the webcast, go to and register for the webinar. After completing the registration, you will be directed to a page with the webinar URL and option to save to your calendar.

First-time zoom webinar/meeting viewers can visit the following page to test access to the webcast system.

Dan Andersen
(515) 294-4210
Twitter: @DrManure

Rachel Kennedy
(515) 294-6685

Melissa McEnany
(515) 294-9075


Iowa Manure Management Action Group
Twitter: @iowamanure

Copyright © 2016, Iowa State University. All rights reserved.


Current News Archives