“Close your windows and go the bathroom in your toilet for a week. Don’t flush. Let it sit there for another two weeks.”
That’s John Klein speaking. He’s a graphic designer and photographer who lives in Michigan’s dairy country, just north of the Ohio border. Klein also serves as director of the Environmentally Concerned Citizens of Southern Central Michigan, and he is describing the smell produced by the farms around his home.
Klein is one of a growing number of rural and suburban residents who consider agricultural odors a problem — or, to use an oft-invoked legal term, “a nuisance.” The issue is driving new science and techniques aimed at taming the most eye-watering emanations.
At the same time, these powerful smells have become a flashpoint for nasty conflicts pitting farmers against their neighbors. Scientists often find themselves caught between these two entrenched sides.
As one expert, Robin C. Brandt of Penn State University, explained in a manual on farm odors: “The non-farming community views odors as strictly a nuisance. A farmer or food processor, however, sees odors as an unavoidable consequence of their livelihood.”
What’s a “Nuisance?”
Accordingly to Charles McGinley, a Minnesota engineer specializing in odors, there are a number of things on farms that produce characteristically offensive odors, including insecticides, chemical fertilizers, and compost.
For sheer stink power, though, experts say manure is the worst, with pig manure the worst of the worst. “There are over 200 compounds in swine odor,” Colin Johnson, extension program specialist at the Iowa Pork Industry Center of Iowa State University. Among them are many of the usual suspects of the odor world, including ammonia, hydrogen sulfide (think rotten eggs), and something called “cadaverine,” which (you guessed it) smells of rotting flesh.
A lot of farmers contend that odors are simply part of farming — end of story. Patricia Roeske raises hogs and turkeys not far from John Klein’s home. She hasn’t noticed any strong odors and still dries her clothes on a line. Moreover, she worries that odor complaints will drive farmers out of business.
“Odor comes with the territory. If you don’t want imported foods, you got to think about what you’re doing to the American farmer,” she says.
For centuries, farmers spread un-composted, “green” manure on their fields as fertilizer. This still happens, mainly in spring and fall. But now, with dramatic increases in the number of animals per farm since the 1980s farm sizes, there’s a lot more manure to deal with.
Farmers know that expansion brings increased odor. “A lot of the calls I get about odor are from farmers being proactive,” says Johnson. “They’re planning to expand their operations and want to know how they can do so without getting odor complaints.”
Not that complaints will necessarily lead to action. Every state has “right to farm” laws that protect farmers from odor complaints produced in the normal course of farming. That means farmers are not liable for reducing livestock odors.
Good Country Air
Klein traces the problem in his area to the late 1990s, when a number of large, new confined animal feeding operations, or CAFOs, began generating odors so extreme that residents’ health is affected.
“We’ve had people get sick in their home due to manure smells. When you have 66 million gallons of manure a year in a small area, you’re going to have that problem.”
The nature of that “problem,” however, depends in part upon what one expects the country to smell like. “Say you moved to the country for the clean air,” says Robin Brandt, who directs the Penn State Odor Assessment Laboratory. “If you are hosting your daughter’s wedding reception while your neighbor is spreading manure, it will spoil the young woman’s special day.”
To help prepare new residents for manure smells, Ottawa County, Michigan produced and distributed a brochure in 2003 called “If You Are Thinking about Moving to the Country.” It included a scratch-and-sniff area that smelled of cow dung. The brochure reportedly led to a dramatic reduction in odor complaints.
Other rural residents say “nuisance” is in the nose of the beholder.
Julie Craves, for instance, is an ecologist and writer who moved to the Michigan countryside after years in the city. Her home outside Ann Arbor is surrounded by farms and farmers — including one guy who, as part of going organic, manured the field across the street twenty times this past summer.
Craves didn’t like it, but she didn’t consider it a nuisance, either. “Compared to industry and city odors, like truck exhaust and factory fumes, I will take cow poop any time.”
The Stink Fixers
If and when a farmer decides to curb odors, there are a lot of different ways to do so. Moreover, they can on a small cadre of stink fixers — scientists like Brandt and extension educators like Johnson.
For farmers looking to build a new hog or cow facility, Johnson likes to run an odor modeling software that “helps determine which location will have the least impact on a nearby city.” (John Klein, however, disputes that such models are sophisticated enough to predict complex factors such as weather.)
Johnson also encourages farmers to plant trees around animal facilities to break the wind and absorb odors. The effect, he says, is partly psychological. “If people see a farm, they smell a farm.”
Brandt has researched and helped teach farmers to use an odor-reducting technique called shallow-disk injection. It’s a bit like no-till farming. Instead of spraying manure on top of a field, it is placed beneath the surface in a narrow slot that is pushed closed immediately, cutting odors by up to 60 percent, according to Brandt.
Besides better odor management, technology can sometimes help. Installing an anerobic digester is expensive — averaging more than $1 million — but it eliminates odors by allowing the manure to rot in a sealed chamber. Over the long term, farmer can earn back a good deal of his or her investment through the methane produced by the digester. For instance, a Pennsylvania farmer named Steve Reinford makes $200,000 a year with his digester by accepting waste for a fee and selling electricity back to the local utility.
Agricultural scientists are also busy researching improvements to animal diet, odor-cutting bedding for barns, and odor-fighting amendments that can be mixed with manure when sprayed on fields.
The digester is the only one of these improvements that wholly remove manure’s stink, however. As Brandt explains, “For a successful amendment, we’re talking a 20 to 30 percent reduction in odors. If you take something that smells bad to begin with and reduce it by 20 to 30 percent, doesn’t it still smell pretty bad?”
That means the stink wars are not going to end anytime soon.