The hairless stem of a waterhemp (right), compared to the hairy stem of the pigweed (left) is the easiest way to differentiate the two species.

Waterhemp difficult to distinguish from pigweed

Using herbicide programs effective on pigweed, should cover waterhemp too, so far

Waterhemp and pigweed species are difficult to differentiate, until they become larger – often past the ideal stage to control the waterhemp species. Mike Cowbrough, weed specialist with OMAFRA, says the herbicide programs identified by the University of Guelph Ridgetown campus, which are effective on waterhemp are equally effective on pigweed and other species. “There […] Read more

An overhead look at the level of control cereal rye has provided when it was seeded the previous fall (mid-November) at 60 lbs acre (left) compared to no cereal rye planted (right).

A double-barreled approach to fleabane control

Combined herbicide-cover crop approach can provide effective control

As herbicide-resistant Canada fleabane and other problem weeds continue to frustrate farmers, more creative control solutions are being sought. Planting cover crops, specifically cereal rye is a good tactic, say researchers from the University of Guelph and the Ontario Ministry of Agriculture, Food, and Rural Affairs. Why it matters: Herbicide-resistant weeds are creating more challenges […] Read more

Plants are particularly susceptible to competition in early growth stages.

Plant stress makes early-season weed control critical

Research shows corn and soybeans can sense the presence of weeds even before emergence

Do you get anxious about weeds in the field? Your crops sure do, and according to new research, yield reductions from early-season weed pressure can happen extremely quickly. Research in the late 1980s established the significant yield impacts caused by weeds if they are not properly controlled early in the growing season, says Clarence Swanton, […] Read more

Steve Shirtliffe demonstrates a min-till rotary hoe.

Evaluating mechanical weed control options

Researchers found that when two methods are used, weed control improves

With the rise of herbicide resistant weeds, researchers at the University of Saskatchewan are looking into alternative weed control methods focused on in-crop mechanical tools to give growers new management options. Why it matters: Farmers are looking for alternative solutions to deal with herbicide resistant weeds that are becoming tougher to control and are affecting […] Read more

Palmer amaranth.

Weed survival can be predicted via imagery

Researchers using imagery to predict viability of Palmer amaranth

Researchers are putting imaging technology to work to improve weed management practices. Maor Matzrafi of the department of Plant Sciences at the University of California, Davis, has been evaluating the use of hyperspectral imaging technology to assess germination and herbicide response in Palmer amaranth. Why it matters: Weed resistance to glyphosate, a broad spectrum herbicide, […] Read more


Peter Sikkema told edible bean growers that 2,4-D is a glyphosate-resistant Canada fleabane control option, if the treatment is registered.

Edible bean growers could get more weed control options

Ridgetown College research shows that older chemistries can help control glyphosate-resistant weeds in strip till

When the Weed Society of America challenged its members to evaluate weed pressure on field crops, Peter Sikkema found that in Ontario edible beans were most challenged by weed pressure. “The crop I work on that is most affected by weed interference is dry beans,” the professor at University of Guelph’s Ridgetown campus said at […] Read more

The xarvio app helps crop scouts and farmers identify weeds, crop diseases and insect damage.

Crop scouting with your smartphone

Smartphone app uses machine learning to automatically identify crop diseases

An app that identifies weeds, insect damage and diseases could change the way crop scouting works. “The reality in field crop scouting for pests today is that looking for disease, weeds and insects is done often with textbooks and apps that make use of manual menus and you compare pictures,” said Warren Bills, business development […] Read more

Dave Bilyea talks to a group about herbicide-resistant weeds at the recent Southwest Diagnostic Days.

How weeds outsmart you

Herbicide resistant weeds proliferate in unexpected ways, making scouting more important than ever

For two scorching-hot days in July, farmers and crop consultants attending the University of Guelph’s Diagnostic Days event at Ridgetown College heard about the birds and bees – of herbicide resistant weeds. A session hosted by Dave Bilyea, research technician at the Ridgetown campus, reviewed the state of herbicide resistance in Ontario and across North […] Read more


In a new University of Illinois study, researchers show large-scale cooperative weed management can slow evolution of herbicide resistance.

Weedy conversations

A new inexpensive tool has emerged in the fight against weed resistance

In a newly released study, scientists at the University of Illinois and USDA’s Agricultural Research Service offer a new tool to fight herbicide resistant weeds that is not only highly effective, it’s free. All it costs is a conversation. Waterhemp, a weedy nemesis of corn and soybean farmers, has developed resistance to multiple herbicide modes […] Read more

VIDEO: Building awareness for emerging weeds

As Ridgetown College’s weed science technician, Dave Bilyea sees a lot of weeds, often brought to him by farmers and rural landowners with questions about what they’re seeing and whether the weed is a concern. Bilyea set up a display of many of those weeds at the Southwest Ag Conference in Ridgetown this year and […] Read more