Thursday, May 6, 2010

Rounded up? No, the varmints got away!

It seems there really is no free lunch....except perhaps for weeds. That's because it turns out that genetically modified crops don't defy evolution after all! The laws of Nature stand, and weren't superseded by agribusiness scientists.

A story in the New York Times this week tells about the increasing resistance of weeds to Roundup, or glyphosate, the weedkiller originally introduced by Monsanto but now sold by a number of other companies. The weedkiller was made for use with 'Roundup Ready' crops, grown from seeds genetically modified to be resistant to the herbicide. Many farmers who planted these seeds were very happy with how easily weeds could be controlled as well as the kind of no-till agriculture, and the reduction in top soil erosion that that brought, that then became possible. (Though there was, and still is, controversy over Roundup Ready crop yields, the safety of the chemical, Monsanto's legal right to insist that farmers can't save seed to plant the following year, and so on, but those issues are not for this post.)

But farmers are growing increasingly unhappy. Roundup resistant weeds -- superweeds -- were first found flexing their new-found muscles in Delaware, but now crop up all over the country (so to speak), with insidious and expensive effects.
To fight them, Mr. Anderson and farmers throughout the East, Midwest and South are being forced to spray fields with more toxic herbicides, pull weeds by hand and return to more labor-intensive methods like regular plowing.
“We’re back to where we were 20 years ago,” said Mr. Anderson, who will plow about one-third of his 3,000 acres of soybean fields this spring, more than he has in years. “We’re trying to find out what works.”
Farm experts say that such efforts could lead to higher food prices, lower crop yields, rising farm costs and more pollution of land and water.
“It is the single largest threat to production agriculture that we have ever seen,” said Andrew Wargo III, the president of the Arkansas Association of Conservation Districts.
Oddly enough, Monsanto originally promised that herbicide resistance would be insignificant. Why? They must have believed they were dealing with so fundamental a vulnerability on the weedy pests' part that they couldn't evolve a way around their assassin.

Monsanto is still saying that the problem is containable -- but they would, since they stand to lose a lot if farmers no longer have reason to buy Monsanto's Roundup resistant seeds. Did Monsanto think that, as one of the largest agricultural companies in the world, that they could make evolution stand still? And of course it's not just glyphosate resistance that's the problem. The International Survey of Herbicide Resistant Weeds lists "347 Resistant Biotypes, 195 Species (115 dicots and 80 monocots) and over 340,000 fields". The additional problem with Roundup is that farmers (and Monsanto) have become dependent on GM seeds, and the cultivation methods they've used to grow them.

The story is of course reminiscent of the increasingly widespread antibiotic resistance in bacteria, though there we had 50 good years, while with Roundup it was only several decades -- neither even a blink of the eye in evolutionary terms, of course. But, we've known for millennia that artificial selection is a fast and powerful force for change -- it was Darwin's very model for how natural selection works in the wild, after all. Farmers have chosen their best animals for breeding probably since they were first domesticated 10,000 years ago.

So, it shouldn't be surprising that in effect artificially selecting for herbicide resistant weeds, or antibiotic resistant bacteria, is fast and effective as well. The idea that we might be headed for the last roundup is naive. Nope, the truth is, pardner, that the varmints are still out there, eluding all the posses we send after them.


Jennifer said...

well, for the record, no herbicides or pesticides on this farm. Any weed control here is done only by letting loose the goats, or old fashioned pulling. Or mulch is good!

Anne Buchanan said...

So, the only resistance would be on the part of the people having to do the pulling?