Why farmers still choose glyphosate

Blog post contributed by Matilda Miranda, freelance copywriter and content strategist.

If there’s one thing that’s helped revolutionize modern agriculture, it’s glyphosate. This weed killer has been around since the ‘70s, but it really took off once genetically-modified (GM) glyphosate-tolerant crops were introduced in the late ‘90s.

For the last few decades, this herbicide has allowed farmers to clear large swaths of land from invasive weeds while causing the least amount of damage to their GM crops, due to their glyphosate tolerance. To date, glyphosate continues to be one of the most widely used herbicides in the world. 

Why do farmers keep going back to glyphosate time and again?

Here are three key reasons:

1. It’s a very effective weed killer

According to the European Commission, glyphosate is the most frequently used herbicide worldwide. Health Canada says it’s the most widely used herbicide in the country and it’s no wonder. Glyphosate’s a broad spectrum herbicide which means it’s effective on almost any kind of plant that photosynthesises and has green leaves. Prior to the introduction of GM crops, it was used only in instances where all plants needed to be cleared out. Andrew Kniss, Weed Science Professor at the University of Wyoming, says GM glyphosate-tolerant crops revolutionized everything.

“That’s really what’s changed agriculture in the U.S. and parts of Canada and South America. They introduced crops where you could spray glyphosate on and they would survive,” he said. “That basically allowed you to use this one herbicide to kill all of the weeds in your field, but leave the crops unharmed.”

Many Canadian farmers agree that it has completely changed the way they tackle weeds, including Jeff Barlow, a farmer from southeast Hamilton, Ont. who grows GMO corn, GMO and non-GMO soybeans and wheat. For the past 20 years he’s been using glyphosate to kill off weeds at Barlow Farms, which has been in his family since 1843. He says it’s the main herbicide he turns to due to its effectiveness.

“I use it more than any other herbicide. Even if the weeds are growing in the spring and even after we plant the [GMO] soybeans,” Barlow said. “There are only a few chemicals you can spray that won’t hurt the soybeans, which are delicate, and one of them is glyphosate.”

Health Canada confirms that “due largely to its broad and flexible use pattern and its wide weed-control spectrum,” glyphosate is the most widely used herbicide in several major crops (such as canola, soybean, field corn and wheat) grown in Canada. It’s also one of only a few herbicides regularly used in fruit orchards and it’s the essential herbicide for use on glyphosate tolerant crops (GTCs), including canola, soybean, corn, sweet corn and sugar beets.

And, like Barlow said, glyphosate has allowed farmers the flexibility of killing weeds not just prior to seeding, but also during and after the growing season, making it an effective weed management program.

2. It’s one of the safer herbicides out there

The wide use of glyphosate by farmers in Canada and worldwide has allowed the use of other less safe herbicides to decline.

“We actually use a lot less pesticides with GMO technology. That’s the whole reason GMOs exist. We can use one pesticide [glyphosate] and it’s a safer pesticide for farmers to use. It’s just so much easier,” Barlow said. 

When it comes to human exposure, Health Canada states that glyphosate is very safe at levels that humans are currently exposed to. Farmers are most exposed to glyphosate since they handle it during their day-to-day activities and the public health agency says that “occupational risks to handlers are not of concern when used according to label directions” which include wearing protective gear (like gloves, eye covers, long pants and a long coat) when handling said chemical. 

Plus, farmers only have to use small amounts of the herbicide. According to Barlow, he only needs the equivalent of three full water bottles to spray land the size of two football fields. “We don’t handle very much,” he said. Emphasizing that the herbicide is diluted into water within the spray.

What about consumers being exposed to glyphosate through eating and drinking? Once again Health Canada (and other regulatory bodies like the U.S.’s Environmental Protection Agency) says that dietary risks from food and water are not of concern for the short and long term. Small traces (think parts per billion – like one second in 32 years) of glyphosate have been found in foods such as cereal, pasta and cookies that are sold in Canada. A Canadian Food Inspection Agency (CFIA) spokesperson told CTV News in a statement that, “to date, none of the levels of glyphosate found in products through the CFIA surveys have been deemed to be a health risk by Health Canada.” Professor Kniss agrees with this statement as well. 

“The amount that you’re finding in foods–a part of that is just the fact that we can detect such low levels of so many things now,” he said. 

In fact, after extensive testing, Health Canada has set the maximum residue levels (MRL) for human consumption “well below the amount that could pose a health concern.” Food producers must have food tested before it can be sold to ensure it does not surpass the MRL. This way, consumers aren’t ingesting any chemical or residue in food at an unsafe amount.

According to Kniss, with any chemical that’s widely used, in this case – glyphosate, it’s not surprising that we’d find parts per billion and trillion in a lot of different things. The levels are just too low to cause any acute and chronic dietary concerns.

3. It helps protect delicate ecosystems

Prior to the introduction of glyphosate, farmers would have to plow or till every field after harvest to get rid of any weeds. It took a lot more time, money and effort but, most importantly, it was damaging the soil microbiome, which is full of microorganisms (like bacteria) that help cycle nutrients and water to the crops.

“The top six inches of soil is the most important. That’s the microbiome. If you lose an inch of it, that would be really bad,” Barlow said. 

Tillage was not only disrupting and destroying the delicate microbiomes that help crops stay healthy, it was also killing earthworms, causing the soil to erode and seep into surrounding streams whenever there was a strong rainstorm and raising CO2 emissions. Thankfully, the use of glyphosate has changed all of that.

“The biggest and most important thing it’s [glyphosate’s] done for us is that we’ve been able to move to a no-till system,” Barlow said. “We can now have healthier soil.”

While Matilda was compensated for her work, her research, wealth of knowledge and ultimate opinions presented in this article are her own.