Genetically modified grass could make superweed problem worse
A genetically engineered grass expected to hit U.S. markets without government review could speed the evolution of hard-to-control weeds, and perhaps require a return to toxic herbicides scrapped decades ago.
On July 1 — a Friday afternoon, a time usually reserved for potentially controversial news — the U.S. Department of Agriculture announced that Scotts Miracle-Gro’s herbicide-resistant Kentucky bluegrass would be exempt from tests typically required of transgenic crops.
Scotts Miracle-Gro is the largest U.S. retailer of grass seed, and the modified grass could be widely used in residential lawns. It’s resistant to glyphosphate, a front-line herbicide known commercially as Roundup.
The grass will survive extra doses of Roundup, allowing more than usual to be applied. That’s the problem, said agricultural biotechnology expert Douglas Gurian-Sherman of the Union of Concerned Scientists.
“The more a chemical is used consistently, the more likely that somebody’s weeds will become resistant. That’s standard, agreed-upon science,” said Gurian-Sherman. “The way that Roundup is used because of transgenic crops exacerbates that problem.”