Glyphosate (Roundup) use soars in recent decades, especially in Midwest, as weeds grow more resistant

Glyphosate use in the U.S. Click the image to enlarge it, or click here for the interactive version.
(Map by the Midwest Center for Investigative Reporting)

Nationwide use of the controversial pesticide glyphosate has skyrocketed over the past 30 years, even as it becomes less effective against weeds and is increasingly the target of health-related lawsuits. According to U.S. Geological Survey estimates, use of glyphosate on crops rose from 13.9 million pounds in 1992 to 287 million pounds in 2016. Glyphosate is the main ingredient in Roundup.

"A review of the agency’s data by the Midwest Center for Investigative Reporting shows that farmers across the Midwest used an estimated 188.7 million pounds of glyphosate in 2016 – nearly 40 times more than in 1992 when they used a total of 4.6 million pounds. The data for the year 2016 is the latest available," Christopher Walljasper and Ramiro Ferrando report for the center. "Farmers in those 12 states – including Illinois, Indiana, Iowa and Nebraska – grow most of the country’s soybean and corn crops. Glyphosate is now the primary way farmers manage weeds that would otherwise reduce the amount of grain they can produce. The Midwest accounts for 65 percent of the nation’s use of glyphosate for crops, according to the center’s analysis."

Monsanto, now owned by Bayer, introduced glyphosate in 1974, but the pesticide became much more popular after Monsanto began selling genetically modified Roundup-resistant seeds. Usage increased even more in 2000 after the patent expired and other companies could sell it. There were at least 40 generic glyphosate-based herbicides on the market by 2007, Walljasper and Ferrando report.

However, as weeds evolved to resist glyphosate, farmers have had to use more of it. James Benham, a longtime farmer in southeastern Indiana, told the center that farmers are in a tough place financially because they have to spend more money on seed and chemicals without seeing more profit. "Sometimes if you timed it just right, you could get away with just one spraying. Now we’re spraying as often as three or four times a year," Benham said. "That puts the farmer in that much more of a crisis mode. Can’t do without it, can’t hardly live with it."