Waterhemp in soybeans.

Timing is critical to scout for waterhemp

This tier one noxious weed must not be allowed to set seed, and once it’s established it’s tough to root out

Manitoba’s weed specialist says it’s time to be vigilant about waterhemp. “We’ve got a lot of waterhemp findings in the province all of a sudden,” Kim Brown-Livingston told the Co-operator. “It’s resistant to multiple herbicide groups, it’s a very aggressive weed, it’s a very prolific seed producer and … you just can’t get rid of

Waterhemp emerges through the canopy of a soybean field.

Waterhemp found in Stuartburn, La Broquerie

The invasive species can cause tremendous yield losses, particularly among row crops

Infestations of waterhemp have been found in the RMs of Stuartburn and La Broquerie in southeastern Manitoba, bringing the known infestations to 10. MARD reported the new infestations earlier this month and urged farmers to keep an eye out for the noxious plant. “If it’s not under control, this could be our No. 1 weed in a


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


Manitoba Agriculture has recently confirmed more cases of Tall waterhemp in the province. It’s a tier-one noxious weed that must be destroyed no matter where it’s found.

New cases of Tall waterhemp found in Manitoba

This is a Tier 1 noxious weed that Manitoba Agriculture wants to prevent from spreading

Tall Waterhemp has been confirmed in four new Manitoba fields and there are rumours of more, Manitoba Agriculture weed specialist Tammy Jones said in an interview Aug. 2. Tall Waterhemp is a Tier one noxious weed that must be destroyed no matter where it’s found, but that can include hand weeding within crops where practical,

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