Super weeds no easy fix for US agriculture-experts [View all]

[MindMover]

(Reuters) - A fast-spreading plague of "super weeds" taking over U.S. farmland will not be stopped easily, and farmers and government officials need to change existing practices if food production is to be protected, industry experts said on Thursday.

"This is a complex problem," said weed scientist David Shaw in remarks to a national "summit" of weed experts in Washington to come up with a plan to battle weeds that have developed resistance to herbicides.

Weed resistance has spread to more than 12 million U.S. acres and primarily afflicts key agricultural areas in the U.S. Southeast and the corn and soybean growing areas of the Midwest.

Many of the worst weeds, some of which grow more than six feet and can sharply reduce crop yields, have become resistant to the popular glyphosate-based weed-killer Roundup, as well as other common herbicides.

Monsanto Co's Roundup worked well for many years. It became prevalent with the commercialization of "Roundup Ready" crops Monsanto developed to tolerate the weedkiller, making it easy for farmers to treat their fields.

But now super weeds have developed a resistance to Roundup, and farmers are scrambling to figure out how to combat their weeds.

"We don't have that next technology. We have to get back to the fundamentals," said Shaw, who chairs a task force that is working with the U.S. Department of Agriculture on how to tackle weed resistance problems.

Several farmers spoke out about their struggles at the summit, as did experts from the USDA and crop consultants.

"This is our number one issue," said Arkansas crop consultant Chuck Farr. "It is a challenge every day, every field."

Harold Coble, an agromist and weed scientist with the USDA, called the problem of weed resistance a "game changer" and said farmers must become more versatile. Too many have simply been relying on the chemicals for too long, he said.

http://www.reuters.com/article/2012/05/10/us-agriculture-weeds-idUSBRE8491JZ20120510