Resistant kochia

Triple herbicide-resistant kochia control

A kochia survey in southern Alberta in 2017 found that all kochia populations were resistant to Group 2 ALS inhibitors, 50% of populations were resistant to Group 9 glyphosate, and 18% of populations resistant to Group 4 (dicamba) herbicides. Kochia populations with triple resistance to…

AC Saltlander foxtail barley

Control foxtail barley and downy brome on saline soils

Where the saline forage site contained root zone salinity approaching severe, the best forage control treatments were AC Saltlander green wheatgrass seeded on 15 or 30.5 cm row spacing. The next best option was alternating rows of AC Saltlander green wheatgrass with slender wheatgrass seeded…

assessing flax

Assessing flax tolerance to new herbicides

Of the seven unregistered herbicides assessed, flax has excellent crop tolerance to fluthiacet-methyl, pyroxasulfone, and topramezone. Flumioxazin caused severe crop damage in high moisture situations and is not recommended for further trials. Field experiments were conducted in 2015 and 2016 at the Kernen Research Farm…

Russian thistle

Group 2 resistant Russian thistle increasing

Of 45 Russian thistle populations tested from central and southern Alberta in 2017, 31 (62%) were Group 2 (ALS inhibitor) resistant. No populations exhibited resistance to Group 9 (glyphosate). A random survey of Russian thistle was conducted post-harvest in fall, 2017. A total of 45…

downy brome

Controlling Japanese and downy brome

Field trials found pyroxasulfone (Focus), pyroxasulfone + flumioxazin (Fierce), and pyroxsulam (Simplicity) provided effective control of Japanese and downy brome in winter wheat. Trials were established at Lethbridge and Kipp, Alberta, and Scott, Saskatchewan, over three growing seasons to compare herbicides for control of downy…

Wild oat head

Over 50% of Alberta fields have herbicide resistant wild oats

Wild oat resistance has increased over three surveys conducted since 2001. In surveyed fields where wild oats were found, Group 1 wild oat resistance increased in Alberta from 11% in 2001 to 58% in 2017. In 2017, 247 fields were randomly surveyed across Alberta prior…

wild oat panicles

Triallate-resistant wild oats also cross resistant to four other Groups

Herbicide screening studies on triallate-resistant (Group 8) wild oats found cross-resistance to Group 1 and Group 2 herbicides. Additionally, unexpected resistance to Group 14 and Group 15 herbicides was found even though the wild oats had never been previously exposed to these herbicides. Two relatively…

Lentil field

Apply Clearfield lentil herbicides at the five to six node stage

The critical weed free period for lentil starts at the five-node stage and lasts until the 10-node stage. Research found that applying Clearfield herbicides to lentils at the five- to six-node stage provided the best weed control and highest yield. Two research studies conducted at…

wild oat in tame oat

Improving tame oat competitiveness with wild oat

Seed 35 seeds per square foot and apply at least 13.4 lbs. P205 per acre to improve wild oat competitiveness and increase tame oat yield. A three-year study was conducted at Agriculture and Agri-Food Canada Indian Head to determine if side-banded phosphorus (P) in combination…

combine wheat header

Diverse crop rotations return up to $45 per acre more

Diverse crop rotations had similar net returns to canola-wheat rotations one-half the time and up to $45 per acre more the rest of the time. Adding integrated weed management practices without relying on wild oat herbicides resulted in similar wild oat pressure as canola-wheat rotations….

wild oat

Our Top 10 herbicide-resistant weed management practices

Agriculture and Agri-Food Canada research scientists Hugh J. Beckie and K Neil Harker identified herbicide-resistant weed management practices that have the most impact on managing herbicide selection pressure. Their top 10 management practices are based on research and growers’ experiences over the last 30 years.