Cornucopia’s Take: Recent surveys across the nation show that some weeds are showing resistance to dicamba, an older pesticide which has recently been reformulated for use in a supposedly less volatile form. Dicamba is touted as an important weapon for farmers seeking to kill weeds which have become resistant to Monsanto’s flagship herbicide glyphosate. The pesticide treadmill will continue to build pesticide resistance in weeds while poisoning the land and its inhabitants. Dicamba and glyphosate are prohibited in organic agriculture.

Trouble in the fields: Why the superweeds are winning
The Des Moines Register
by Nathan Donley, Center for Biological Diversity

Palmer amaranth in the field
Source: Delaware Agriculture

Across a 1,000-mile long expanse of farm country from the Great Plains to the Midwest, millions of acres of crops have withered, leaving some fields little more than a brown swath of death.

With thousands of complaints of crop damage across more than 3 million acres in 24 states — including some 100 complaints in Iowa — a longtime University of Missouri plant researcher is calling it possibly the greatest pesticide-caused crop damage in U. S. history.


The culprit is the notoriously drift-prone pesticide dicamba that was supposed to be the answer to weeds’ escalating resistance to the world’s most popular pesticide — Monsanto’s glyphosate, the active ingredient in Roundup.

As glyphosate-resistant superweeds sprouted across millions of U.S. acres, farmers were assured that spraying both dicamba and glyphosate on a new generation of Monsanto crops genetically altered to resist both pesticides would be the cure.

But the latest pesticide “solution” has created new problems for farmers who choose not to plant those GE crops. With more than 2,600 complaints of widespread damage to soybeans, fruit trees and vegetables, eight states have limited use of dicamba and several class-action lawsuits have been filed against Monsanto.

More than simply an indictment of one pesticide, the dicamba dilemma has spotlighted the challenges of the nation’s increasing dependence on crops genetically altered to resist pesticides, a dependence that has directly fueled an even greater addiction to highly toxic chemicals.

The seeds of the current problem were sowed in the mid 1990s when Monsanto introduced its genetically altered seeds that resist glyphosate and urged farmers to liberally douse the fields in the pesticide. “Dead weeds will not become resistant,” the company told farmers.

As annual U.S. glyphosate use soared to 300 million pounds, its over-use accelerated development of the superweeds farmers are now battling by spraying even more pesticides, including dicamba.

And the dicamba lawsuits may be the least of the problems for the company that once assured farmers that glyphosate was safer than table salt.

More than 1,000 lawsuits have now been filed against Monsanto by people claiming they developed non-Hodgkin’s lymphoma from exposure to Roundup.

The lawsuits have come in the wake of a World Health Organization analysis linking glyphosate to cancer. And California, which in July declared glyphosate to be a known carcinogen, is now considering requiring cancer warnings on Roundup labels.

So ubiquitous is glyphosate that today its residues are found in many waterways and foods, ranging from baby food to Ben & Jerry’s ice cream.

And the dicamba problem isn’t likely to go away anytime soon.

Monsanto is predicting annual use of dicamba will increase from around 5 million pounds in 2014 to at least 30 million pounds in the next three years.

And as use of the pesticide rolled out as the latest “solution” to weed resistance soars, recent surveys across the country make clear the false hope of the nation’s dead-end stroll on the pesticide treadmill:

Some weeds are already evolving resistance to dicamba.

Nathan Donley, PhD is a former cancer researcher who is now a senior scientist at the Center for Biological Diversity.

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