GFM Network News


Herbicide resistance is a growing concern due to glyphosate-resistant kochia (seen here) and the yet small but aggressively spreading waterhemp.

Former weed specialist back on the job

Battling weed resistance will be hard work, says Kim Brown-Livingston

Kim Brown-Livingston says she’s optimistic as she takes the role of provincial weed specialist. “We have a great future,” she said. “We’re going to continue on, and our farmers are doing a really good job of it now.” Brown-Livingston previously held the role of weed specialist from 1998 to 2013 before moving on to work

In this photo from Mike Cowbrough’s October 2019 Pest Patrol column in Country Guide, light-green waterhemp plants approach the top of a soybean canopy after two ineffective applications of glyphosate. (Supplied photo)

Group 27 herbicide resistance arrives in Canada

Mesotrione-resistant waterhemp confirmed in Quebec

A persistent and fiercely competitive weed that has developed resistance to several herbicide groups since its arrival in Canada is now the first in the country to fight off a Group 27 product. Quebec’s Reseau d’avertissement phytosanitaire (RAP) last Friday reported a patch of waterhemp with resistance to mesotrione herbicide in the Haut-Richelieu municipality, in


Herbicide-resistant wild oats are still controlled by glyphosate — for now.

Now’s the time to find resistant weeds

Herbicide-resistant weeds are on the rise and pre-harvest is a good time to find them

Delaying the onset of herbicide-resistant weeds isn’t a lost cause. In fact the more vigilant a farmer is the more success they’ll have, says Ingrid Kristjanson, a farm production extension specialist with Manitoba Agriculture and Resource Development (MARD). With farmers checking crop maturity as harvest grows near, it is also a good time to scout


Provincial weed specialist Tammy Jones says leaving small patches of survivors can quickly result in a huge problem as new and highly competitive herbicide-resistant weeds have arrived.

Losing the war on weeds

Tammy Jones has been doing the math on where herbicide resistance is taking Manitoba farmers and the numbers are grim

Tammy Jones spent four hours last summer wrestling with about 300 waterhemp plants in a Manitoba field, yanking them out of the ground by the roots and carrying them to the field edge for destruction. The provincial weed specialist was trying to demonstrate the value of controlling what might seem to be small patches of


The researchers started with a single seed of Amaranthus hypochondriacus, their test plant, and grew generations of the plant to produce the seeds they needed for their experiments.

New mutations for herbicide resistance rare

Most resistance seems to come from pre-existing genetic conditions

After exposing more than 70 million seeds to a soil-based herbicide, researchers at the University of Illinois were not able to find a single herbicide-resistant mutant. Though preliminary, the findings suggest that the mutation rate in amaranth is very low, and that low-level herbicide application contributes little — if anything — to the onset of

Manitoba Agriculture’s 2018 in-season survey now documents 12 municipalities with glyphosate-resistant kochia.

Glyphosate-resistant kochia confirmed in 12 municipalities in 2018

Testing is the only way to confirm how widespread glyphosate-resistant kochia is in Manitoba

When Tammy Jones’ phone rang last year as often as not it was farmers fed up with kochia spreading in their fields. The Manitoba Agriculture weeds specialist dubbed the tumbleweed ‘weed of 2018,’ in a talk at St. Jean Farm Days last week. “We saw a lot of it,” she said. “It felt like anyone

A depiction of the herbicide molecule (top), which inhibits an enzyme (bottom) that plants need.

Neutralizing weeds’ defence system

Researchers identify a new mechanism to battle herbicide resistance

Plants and unseen soil micro-organisms all need precious space to grow. And to gain that space, a microbe might produce and use chemicals that kill its plant competitors. But the microbe also needs immunity from its own poisons. By looking for that protective shield in micro-organisms, specifically the genes that can make it, a team


Webinar Australia: Chemical company BASF has launched a free resource for farmers on herbicide resistance, including lessons from Australia.

Transplanting herbicide-resistance advice from Down Under

Australia has something to teach Canadian farmers about herbicide resistance, at least, according to BASF’s latest online resource

On the other side of the world, farmers have learned some valuable insights about herbicide resistance that you can share. In Australia they’ve long been fighting this battle and the land Down Under has learned some tough lessons. The International Survey of Herbicide Resistant Weeds found Canada is third in the world in terms of

Editorial: In the weeds

Canada has a brewing weed problem, and we’re not talking about the looming legalization of cannabis. This is an older problem, but with a modern twist, in the form of constant selection pressure from chemical control products and the resulting herbicide-resistant weeds. Manitoba farmers have the dubious distinction of being among the first in the