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Editor’s column

Herbicide resistant weeds — a very real threat

In this issue of Grainews we’re focusing on crop production and protection.

In Western Canada, any talk about crop protection is probably going to include some talk about herbicides, and any talk about herbicides is bound to come around to a discussion about herbicide resistance. This is a growing issue in Canada and around the world. The problem really hit home when glyphosate-resistant kochia in Alberta was confirmed in January.


In October 2011 the CBC broadcast a radio documentary called “Superweeds” on its weekday morning show The Current. In the slightly-scary introduction, the CBC host referred to Roundup-resistant weeds as “the stuff of agri-chemical nightmares.”

The radio program focused on glyphosate-tolerant weeds. When the program was aired, none had yet been confirmed in Western Canada. But Hugh Beckie, Agriculture and Agri-Food Canada scientist, had already predicted that this would happen sooner or later. As he told the audience at the Crop Production Show in Saskatoon, “If you use a product frequently enough, you will eventually select for resistance.” There is already a list of weeds resistant to other chemicals (not glyphosate) in Saskatchewan’s 2011 Guide to Crop Protection.

Plants are crafty. They’ll do whatever they can to survive and reproduce. When a few plants survive a chemical application, they’ll pass on their ability to survive to the next generation. Researchers can develop a new herbicide, but the same thing is likely to happen again, and keep happening. On the CBC radio show, University of Saskatchewan researcher Chris Willenborg referred to this as “getting on the pesticide treadmill.”

As long as chemical companies keep developing new, patented (expensive) chemical formulations that kill weeds, we can keep running on that treadmill. In fact, Dow AgroSciences is well on its way to developing seed with tolerance to 2,4-D.

While we were taking Christmas holidays, Dow staff were petitioning the U.S. Department of Agriculture for deregulation of its new genetically engineered corn (currently known as DAS-40278-9). The USDA’s Animal and Plant Health Inspection Services (APHIS) has concluded that the new corn is “unlikely to pose a plant pest risk,” but the USDA is taking comments on the issue until February 27, 2012.

Although some corners of the Internet are abuzz with anti-genetic-engineering groups urging members to submit negative comments, 2,4-D-tolerant crops are likely to be the next big tool for farmers. Dow expects to release the new corn variety in the U.S. in time for seeding in 2013, and we’ll see other 2,4-D-tolerant varieties in Canada in the near future.

Running on the treadmill will keep us producing high volumes of crops. But what if the treadmill slows to a crawl? 2,4-D was developed during the Second World War. Glyphosate came out in 1974. A lot of the new chemicals announced in the past few years are minor changes to existing formulations, or new pre-mixes of “old” chemicals. As Hugh Beckie reminded attendees at his presentation, “herbicides are a non-renewable resource,” and “the pipeline is dry.”

Preserving the technology

While we’re waiting for tomorrow’s chemicals to show up in our local dealers’ sheds, we need to take individual responsibility and do all we can to keep today’s chemicals effective for as long as possible.

The most important step we can take on our own farms is to use recommended rotations — for crops, herbicides, and even fungicides, as you read in our cover story by Angela Lovell.

Herbicide rotation can get complicated. This is mainly because we usually refer to chemicals by their brand names, not their active ingredient. (When was the last time someone told you they were off to town to pick up some tralkoxydim?) You could change products from one year to the next, but find out you’ve used the same active ingredient. This gets even more complicated when you’re mixing more than one product.

Because we generally refer to chemicals by their trade names, it can be very easy to change chemicals annually but still accidentally use the same active ingredient in the same field two or more years in a row.

To make sure this doesn’t happen to you, Alberta farmer Gerald Pilger has taken the time to pore over the chemical information and put together some handy lists of active ingredients in popular chemicals. You’ll find the active ingredients of Group 1 chemicals on page 8 of this issue. You’ll have to wait for the next issue of Grainews for the information about Group 2 chemicals.

Moving between groups

The first key to understanding herbicide rotation is learning about the different chemical groups. After reading a lot of brochures and websites about proper chemical rotations, I can’t say I had even a vague understanding of the actual differences between groups, or how the chemicals were sorted into groups.

So late last fall, I was very pleased to read one the regular email agronomy updates from our local grain buyer, the Weyburn Inland Terminal. Brian Woodard, an agronomist at WIT, had put together a helpful, readable summary of how the chemicals in each of the groups kill weeds. When I asked Woodard if we could run his update for Grainews readers, he was happy to comply. I hope you’ll find his article as interesting as I did. He not only explains what chemicals in different groups do, but also points out why some chemicals should be applied at dusk and others during sunlight hours. Find Woodard’s article on page 14.

Day of the Triffids

The CBC ended its radio documentary “Superweeds” with a sound clip from the 1962 movie “The Day of the Triffids.”

In the movie, alien plant spores are transported to Earth in a meteor shower (which, coincidentally, also blinds most humans). These triffids can walk, have a poisonous sting and enjoy feeding on animals and the newly-blinded people.

I suppose the film version was slightly less sinister, politically speaking, than the 1951 book with the same title. In the book version, the triffids were bioengineered by a Russian scientist, accidentally released into the wild and cultivated widely due to their superior properties (before people realized they were evil).

So although the movie didn’t blame evil plant breeders for the chaos, I still think the CBC’s sound clip was intended as a scare tactic. One of the lines from the movie that the CBC included to close off the documentary was: “All plants move, but they don’t usually pull themselves out of the ground and chase you.”

I don’t think there’s any need to end this column with that sort of fear-mongering. Farmers are landowners with a long-term stake in the fields. We have big investments in our businesses — both financial and personal. While we’re generally grateful for new technological developments and quick to jump on board when there are new products on offer, maintaining the effectiveness of the solutions we already have will be easier on our wallets and provide us with more peace of mind.

New baby for Grainews editor

(No — not me. I’m the Acting Editor.) Everyone at Grainews sends congratulations to Lyndsey Smith and her husband on the birth of their Friday the 13th baby, Elliott. Please turn to the Wheat and Chaff page to see a photo.


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