GFM Network News


Figure 1: Light green waterhemp plants approaching the top of the soybean canopy after two applications of glyphosate that proved ineffective. At this stage, no herbicide will adequately control waterhemp.

Pest Patrol: Plan to manage waterhemp in 2020

#PestPatrol with Mike Cowbrough, OMAFRA

Reading Time: 2 minutes Waterhemp has spread further across Ontario during the 2019 season and can now be found in eight counties (Bruce, Chatham-Kent, Essex, Haldimand, Lambton, Middlesex, Norfolk and Northumberland). A close relative of pigweed, waterhemp is a competitive annual broadleaf weed that has been found resistant in the province to four different herbicide groups (Group 9: Roundup, […] Read more

AAFC tests have been on a pull-type Harrington Seed Destructor, but a newer version is integrated with the combine.

Weed control from the back of the combine

Prairie manufacturers are offering chaff collectors, and AAFC continues tests with the Harrington Seed Destructor

Reading Time: 4 minutes Mechanical weed control hasn’t been widely adopted in Western Canada but it soon will be, says Trevor Thiessen of Redekop Manufacturing in Saskatoon. “We don’t have the same stress on the resistance issue that other parts of the world are seeing. In Canada, we’re five years behind Australia in terms of thinking about mechanical weed […] Read more


Figure 1: Purple deadnettle in a wheat field — October 2018 at a yield-reducing population density of around 500 plants per square metre.

PHOTOS: Pest Patrol: Purple deadnettle and henbit control in winter wheat

#PestPatrol with Mike Cowbrough, OMAFRA

Reading Time: 3 minutes Q: I’m seeing more henbit and/or purple deadnettle in my winter wheat crop. Should it be controlled, and how? A: Henbit and purple deadnettle are often discussed interchangeably because they look similar, are from the same genus (Lamium) and have similar emergence patterns (mainly in the fall, but henbit will also emerge in spring). Both […] Read more

David Kaminski, a field crop pathologist with Manitoba Agriculture, urges producers to be aware of nearby streams when picking oat varieties, thanks to the prevalence of common buckthorn, a wild host for crown rust.

Wild host a thorn in the side for oat growers

Common buckthorn is a haven for crown rust spores over the winter and an easy source of infection if the farmer opts for a susceptible oat variety

Reading Time: 2 minutes Oat growers may want to gauge the distance to the nearest woody stream bed the next time they choose a variety. That’s one of the messages sent out during this year’s Crop Diagnostic School in Carman in the first two weeks of July. Why it matters: Manitoba’s most popular oat varieties have either been downgraded […] Read more


Although it has yet to be confirmed in Ontario, Palmer amaranth is capable of rapid spread and should be treated as glyphosate resistant.

Recognize the threat of these invasive weeds

How big a problem can waterhemp and Palmer amaranth really be? Let’s not find out

Reading Time: 7 minutes Has everyone been crying wolf about waterhemp? After all, haven’t we been hearing warnings in southern Ontario about the weed for the past 15 years, and who has lost a bushel? Well, it was actually 17 years ago — 2002 — when the species was first confirmed in Lambton County, and the good news is […] Read more

Dr. Clarence Swanton.

Pest Patrol: Thank you, Dr. Clarence Swanton

#PestPatrol with Mike Cowbrough, OMAFRA

Reading Time: 2 minutes “Matty Cowlick” is indifferent to the recent retirement of Dr. Clarence Swanton, weed scientist in the department of plant agriculture at the University of Guelph. But I’m happy for him. I’m happy that Clarence will continue with his research program and to advise graduate students, and happy that he will have more time to spend […] Read more


Figure 4.

Pest Patrol: Use your phone to capture and document pest activity

#PestPatrol with Mike Cowbrough, OMAFRA

Reading Time: 3 minutes “If you want to have the upper hand on weeds, you need to know every little detail about their existence.” The above quote is straight from the great Jack Alex, retired botany professor and herbarium curator at the Ontario Agriculture College, who used to repeat it to me at every opportunity. Fortunately, most of us […] Read more

Some plants along the rail line are glyphosate resistant.

Pest Patrol: Sanitation of weed seed

#PestPatrol with Mike Cowbrough, OMAFRA

Reading Time: 3 minutes Q: Can we stop the spread of weed seeds? A: “I’ve been thinking a lot about sterility lately.” I knew as soon as the words came out of my mouth that I had slipped up. I was responding to a question in the audience at a local crop conference about ways to stop the movement […] Read more


Growers in the U.S. are dealing with the spread of Palmer amaranth, which overcame glyphosate as far back as 2010.

Better herbicide tolerance technologies are on the way

Better technologies are coming, but we’ll need patience and shrewd management until they arrive

Reading Time: 4 minutes Count off the many challenges facing a farmer in any growing season and outside of weather conditions, the biggest impediment has to be weed management, particularly as it relates to herbicide tolerance. In spite of the importance of varietal or hybrid selection and fertility, and the potential for yield losses from insect pests and diseases, […] Read more

Palmer with long terminal seed head.

PHOTOS: How to identify Palmer amaranth

Reading Time: < 1 minute The amaranth species look fairly similar as seedlings. Nobody wants to wait until they’re in seed to figure that out. When in doubt, ask an agronomist.” — Tammy Jones, Manitoba Agriculture. For the latest information, visit the North Dakota State University website.