Here’s what caused the manure smell across Minnesota this week

ST. PAUL, Minn. (GRAY) – Many Minnesotans on social media seemed slightly confused about the manure-like odor that wafted through the state this week.

“Every fall, I pretty much smell it. And just because of my nature, the nature of my work, I noticed that pretty quickly,” said Melissa Wilson, associate professor at the University of Minnesota, who specializes in manure nutrient management and water quality.

Experts like Wilson say it’s a fairly straightforward phenomenon, and it actually happens quite often.

Come fall, farmers across the region lay out fertilizer in anticipation of the winter.

“We’re actually taking the nutrients that are generated from the animals and recycling it back to the fields so that it can be used for crop production in the next year,” Wilson said.

Typically that happens just before a big freeze, and the ground freezes over before the smell gets too noticeable; but when you get a cold snap like the one at the beginning of this month, followed by an unexpected bout of 60-degree weather, it’s the perfect way to carry those smells up into the air.

“It’s really unusual to have 70-degree temperatures in the middle of November, so that was probably why the smell was so strong,” said Matt Tarldsen with the MPCA.

Still, the phenomenon is perfectly natural and keeps the state’s agriculture alive and well.

“Yes, it stinks. And that’s kind of one of the drawbacks of this type of work,” said Wilson, “But just reminding [people] that it is nutrients and we are recycling those nutrients back to the field. It’s a stinky job, but it needs to get done.”

The smell dissipated as a cold front moved in and pushed the air out, and according to the MPCA, that cold-front will likely remain here through Thanksgiving.

“It’s one of those things where once the fertilizer is down for a while, it won’t smell as much as time goes on,” Taraldsen said.