This Failed Experiment Is Still Causing Farmers Trouble Almost a Decade Later

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Nine years ago, an E. coli outbreak led to an expensive, labor-intensive change to the way a lot of our farms operated. But things didn’t get better—in fact, they got worse.

In 2006, there was a particularly nasty, in some case even fatal, E. coli outbreak spreading around the nation. The source? California’s spinach fields. Though the precise chain of events wasn’t ever uncovered, many people thought it may have something to do with the farm’s livestock, and a movement to keep livestock farms and crop farms separate kicked off.

So how well did it work? A new study in PNAS from researchers at the University of California Berkeley looked into the question nine years after the fact by testing for pathogens at farms all around California and found that, not only had the presence of E. Coli and Salmonella not decreased, they had actually increased since the changes. And, in the farms that hadn’t isolated their livestock, there was no increase in either E. Coli or Salmonella.


Instead, the researchers suggest that a better strategy would be to replant “buffer” vegetation around the crops, many of which were clear-cut to make the fields less appealing to animals, when the strategy first kicked off.

Image: USDA/flickr