Meet Palmer Pigweed. Palmer’s a hearty fellow.
He’s capable of growing 2 to 4 inches per day until he’s 8 feet tall. His weed stalk is as thick as a man’s wrist and tough enough to damage farm machinery.
Palmer’s friendly to humans. Native Americans grew him for food. But he’s highly competitive with other plants, sucking up their water and nutrients and shading them out with his thick, bushy leaves.
And talk about sexual prowess: Palmer’s prolific releases of airborne pollen can fertilize hundreds of his female favorites who each disseminate about 600,000 tiny seeds.
But most important to farmers, Palmer’s a survivor. Recently, he survived a massive campaign to poison him with the herbicide glyphosate. Although many of his kind died in that campaign, Palmer was naturally resistant to glyphosate, and not only did he survive but he and his progeny began to spread at an incredible rate.
Palmer made his first appearance as a “super weed” – a weed mostly or wholly resistant to glyphosate – when he was discovered in North Carolina in 2005. By 2014, Palmer’s progeny had spread to 32 states in an unbroken chain from Florida to California, throughout the Southeast, up the Atlantic coast and to most of the Midwestern “agricultural heartland” states.
Palmer can be devastating to agriculture. As Stanley Culpepper, an agronomist with the University of Georgia Cooperative Extension put it, “(Palmer’s) the first real weed pest that can come on your farm, you see it in year one, and by year three, it dominates the entire landscape.” Even moderate infestations can destroy half to two-thirds of cotton and soybean yields and significantly damage corn fields. Palmer already has cost farmers billions of dollars and is a threat to the America-dependent global food supply.
Worse, Palmer is not alone. The International Survey of Herbicide Resistant Weeds lists 13 species of glyphosate-resistant weeds in the U.S., 32 worldwide. While not all the weeds are as potent as Palmer Pigweed, many are quite robust and cumulatively they represent a huge threat to agriculture.
This burgeoning disaster originated with the overuse of glyphosate, distributed mostly by the Monsanto company under its “Roundup” brand. In 1996, Monsanto began introducing glyphosate-resistant, “Roundup Ready” crops, including soybeans, corn, cotton, alfalfa and sugar beets, and much of the U.S. agricultural community thought it had discovered a panacea.
Farmers could spray Roundup on their fields, kill weeds without damaging crops and save money by skipping traditional weed-management practices such as crop rotation and tilling. Also, glyphosate is arguably the least environmentally damaging herbicide, and the no-till agriculture it enabled benefited the soil and the environment.
Soon, most of the country’s soybean, corn and cotton acreage was Roundup Ready, and many weeds were eradicated. Shortly thereafter, however, a few Roundup-resistant weeds began to appear. Most farmers responded by significantly increasing the amount of Roundup they used, which, in a losing effort, eliminated some but not all of the resistant weeds.
Exasperated and endangered, many farmers began using stronger herbicides, returned to tilling to control weeds – and began to question why they were using Roundup and Roundup Ready crops in the first place.
By 2014, Monsanto’s competitor Dow AgroScience had come up with a solution. It got the USDA and EPA to approve its new line of genetically modified corn and soybean crops that are resistant to two herbicides, glyphosate and “2, 4-D,” an ingredient of the Vietnam-era defoliant Agent Orange. According to Dow, this new one-two punch will prevent the continuing evolution of weeds – just like glyphosate did at our ecological house.
Philip S. Wenz, who grew up in Durango and Boulder, now lives in Corvallis, Oregon, where he teaches and writes about environmental issues. www.your-ecological-house.com.
