What about Roundup?
There is no shortage of criticism leveled against the use of herbicides like Glyphosate (often referred to as Roundup). Critics have shouted about its use in food crops for years, blaming glyphosate use for everything from autism to obesity. But university researchers and experts from the Environmental Protection Agency (EPA) tell a much less salacious story: when glyphosate is used properly, it’s a safe and important component of food production.
What is Glyphosate?
Glyphosate is a widely used herbicide that controls broadleaf weeds and grasses. It has been registered as a pesticide in the U.S. since 1974. Products containing glyphosate are sold in various formulations, including as liquid concentrate, solid, and ready-to-use liquid. Glyphosate is used in products such as Roundup® to control weeds in both agricultural and non-agricultural settings. Glyphosate can be applied using a wide range of methods, including aerial sprays, ground broadcast sprayers, and more.
Agricultural uses include corn, cotton, canola, soybean, fruits, vegetables, cereal grains, and more. All usage of glyphosate must be done in accordance with the safety instructions from the EPA, which is detailed and sparing. Most applications call for only a few ounces per acre, diluted in 20 gallons of water or more.
“We have a saying that the label is the law,” said Ian Burke, professor of Weed Science at Washington State University. “In a full undergrad course, we can barely scratch the surface of the regulatory framework that herbicides are delivered under. They’re among the most regulated chemical compounds in the world.”
Why do wheat farmers use glyphosate?
Weeds are a problem in nearly every crop, no matter where it is being grown. But in the dry, semi-desert regions of Eastern Washington, weeds steal valuable moisture and nutrients from the wheat crop, and if they’re not controlled properly, they can completely choke out the wheat crop altogether. Since farmers can’t control the weather and make more rain, they focus on what they can control: weeds.
Historically, farmers have used tillage to control weeds - before the wheat crop is planted, mechanical tillers break up the soil and disturb the roots of the weeds so they can’t start the growth cycle. Theoretically, by the time the weeds can reestablish their roots, the wheat has already been planted and grown to the point where it can out-compete the weeds for moisture and nutrients.
Tillage is a proven method for weed control, but in recent decades, farmers have made an effort to use less tillage (or in some cases, no tillage) in order to reduce soil erosion. But less tillage inevitably means farmers need another option for weed control: chemical applications like glyphosate.
“The herbicides we have available today are, in my opinion, the safest and most effective we’ve ever had,” said Burke.
Responsible Use
In addition to the stringent restrictions given by the EPA, farmers also limit what times of the year they use the chemicals. In Washington, farmers don't spray their actual crop with glyphosate...ever. They spray it on fallow fields before seeding, in some cases a full year before harvest - so there's never any residue on the harvested kernels.
As if that weren’t enough, farmers are often restricted even further by their own self-interest. Chemicals like glyphosate are expensive, and farmers are stereotypically stingy - so they aren’t likely to use one more drop than they need.
Farmers work closely with university researchers like Professor Burke at WSU, and with crop advisors from retailers like the McGregor Company, Nutrien Ag Solutions, and Wilbur Ellis to make sure that they’re using the right amount of the right herbicide.
“We can’t do this without herbicides,” said Burke. “We’ve tried. They’re expensive, and if we could do without them, we would. Farmers have to use them, but they’re using them in the most practical, economical way they can.”