Weeds are an eyesore, and the bane of many a homeowner. But they can also be very, very costly. In fact, if left alone weeds could lead to billions in economic losses in the United States each and every year.
A Lot of Green
A 2016 study, co-authored by the Weed Science Society of America (WSSA) and contributors from Kansas State University (KSU), examined this very issue. According to their research, allowing weeds to grow uncontrollably would cause US/ Canadian yields of both corn and soybeans to drop dramatically, to the tune of approximately 50 percent. In monetary terms, this would equate to annual losses of $43 billion.
Given that both the US and Canada are major producers and exporters of both corn and soybeans, such losses would have worldwide consequences. No country produces more corn or soybeans than the United States, while Canada is the world’s 7th largest soybean producer and 11th largest producer of corn.
The study’s lead author, Kansas State University professor Anita Dille, stated that the researchers “were interested in trying to understand just how much impact weeds still have on our crops. Despite the great improvements we have in crop genetics and fertility, we’re still having to manage weeds.” Dille argued that the report highlighted the need for farmers to stay vigilant when it comes to controlling weed growth. “We wanted to document that weeds were still a significant pest to manage, that we need to maintain all the different weed control practices that we have. There’s a lot of pressure on the industry to say, ‘hey, stop doing this or that.’ We wanted to highlight that these weeds are still so important and that we need to come up with every option that we can to manage them.”
A Resourceful Enemy
There are multiple ways to remove harmful weeds. The most obvious option is the use of herbicides; another possibility is to allow insects to gobble down these unwanted plants. A third method of weed control is to plant crops relatively close together, thereby denying weeds the nutrients they need to grow. A fourth option is to alter the soil using specific agricultural vehicles, a process usually referred to as tilling.
According to Dille, farmers should not adopt a one-size-fits-all approach when it comes to fighting weeds. Instead, they should first determine what type of weeds they are dealing with, and use more than one of four common weed-killing methods.
“Weeds are smart. They keep figuring out how to survive whatever we throw at them,” Dille said in a Kansas State University press release. “The reason some people ended up with herbicide resistant weeds is that they often used a really good product over and over again and the weeds weren’t exposed to other control practices. If we change it up, keep the weeds on the defensive, then they potentially won’t become resistant because we’ve controlled those resistant ones with a different technique.”
For their report, the study authors relied on data from scientists who study the growth and behavior of weeds. Each year, these scientists conduct studies involving crop plots, some of which have not been treated with herbicides. The WSSA/KSU team also reviewed information provided by the U.S. Department of Agriculture’s National Agricultural Statistics Service and Statistics Canada. This allowed them to put a price tag on weed-related crop damage.