The University of Nebraska has now identified seven weeds resistant to common herbicides, especially the one sold under the brand name Roundup.
That's trouble, especially for soybean farms like Clay Fisher.
He said with a laugh, "I don't feel like going out pulling them like we used to."
Farmers have better things to do than pulling weeds. But spraying isn't working like it was.
"We had a lot of pressure this year, seems I better learn how to control them next year, it's pretty much too late on anything this tall," he said, gesturing waist-high.
The problem is, things like ragweed and waterhemp have become resistant to the herbicide glyphosate, better known as Roundup.
UNL Extension Weed Specialist Amit Jhala said, "We are dealing with some weed problems like herbicide resistant weeds, specifically glyphosate resistant - marestail, common waterhemp, giant ragweed and koncia we have confirmed in Nebraska."
Roundup has been widely used the past 20 years, ever since the introduction of Roundup Ready seeds in 1996. Farmers could spray roundup without harming crops, And it was working well on weeds.
Jhala said, "Most of the growers were totally dependent on only post emergent applications of glyphosate two or three times, that's why we have resistant weeds now. There was lack of diversity in weed control."
At a field day near Clay Center, experts explained farmers may need to apply different herbicides, at different times.
"Because our options are limited and we're running out of options," said Jenny Rees, a UNL Extension Educator in Clay County.
Scientists are testing different treatments to find unbiased answers.
Jhala said, "Including herbicides from all different companies so growers can decide what to choose."
That's what farmers like Clay Fisher want, answers to weeds growing in their soybean fields.
He said, "Waterhemp for sure this year got tall, definitely glad somebody's getting us some answers what to do about that."
There are more herbicide options for corn, and fewer for beans.
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