Weed Control Program Research Posters

Roundup Ready Canola Control in Roundup Ready Soybean (2014)
rr-soybean

Volunteer canola in soybean can compete for moisture, nutrients, and light, thereby reducing crop yeild, harvesting efficiency, and seed quality.  successful weed management is one of the most vital aspects of profitable soybean production as competition with weeds ca cause substantial reductions in soybean yield and quality.  However, control of herbicide resistant volunteer canola can be challenging for soybean growers.  As soybean acres spread northwest into Saskatchewan, it is likely that a large portion of the soybean acreage in western Canada will be...

A brief history of herbicide use in Western Canada (2009)
Herbicide History
Throughout the history of agriculture, more time, energy and money have been devoted to weed control than to any other agricultural activity. The widespread use of herbicides is a very recent phenomenon, becoming a significant factor in crop production in the 1960s (Guide to Farm Practice 1942. University of Saskatchewan). Currently, herbicides account for approximately 80% of total pesticide sales in Canada and about 75% of those sales are in western Canada. Thus, in 2006, western Canadian farmers spent approximately $800 million on herbicides. (CropLife Canada Annual Reports, 2005 and 2007)....
Control of Group 2 (ALS) Resistant Kochia (Kochia scoparia) in Spring Wheat (Triticum aestivum) (2008)
kochia
In the 20 years since Group 2 herbicide resistant kochia was identified on the Prairies, the resistant biotype has spread dramatically from its original area of adaptation in the Brown and Dark Brown soil zones to the Black soil zone. A survey of over 100 fields across the Prairies (majority in Alberta) conducted by AAFC in 2007, revealed that about 90 percent of the fields contained Group 2 resistant kochia biotypes confirming results from a survey conducted by Manitoba Agriculture in 2004. In addition to widespread use of Group 2 herbicides for broad leaved weed control in cereals, the rapid spread of Group 2 herbicide resistance in kochia was enhanced by several different factors: At least three different target site mutations in kochia confer resistance to Group 2 herbicides. In addition, kochia is an out crossing species, so the dominant resistance gene can spread throughout a population quickly. Prolific seed production, a low level of seed dormancy and kochia's tumbleweed seed dispersal mechanism also contribute to rapid spread of resistant biotypes....
Timing of Spring Application for Winter Annual Weed Control (2007)
Spring Timing
Winter annual weeds like flixweed (Descurainia sophia), shepherd's purse (Capsella bursa-pastoris), narrow-leaved hawk's-beard (Crepis tectorum) and stinkweed (Thlaspi arvense) can remove a lot of soil moisture in the spring as they begin to grow very early and are very inefficient water users. With farm size increasing and seeding taking 4 weeks or more, winter annual weeds may be robbing crop yield if not controlled early....
Winter Annual Cleaver (Galium aparine) Control (2007)
Annual Cleavers
In Saskatchewan, cleavers has been predominantly a spring germinating annual weed. However, with the rapid adoption of direct-seeding systems and a resultant increase in snow cover, this species has begun to behave as a winter annual in many locations. Over-wintered plants are usually in the 8-10 whorl stage by the time pre-seeding burn-off herbicide treatments are applied in the spring. This is well past the growth stage specified on herbicide labels. Therefore, a trial was conducted in the dark brown soil zone at two locations near Saskatoon in 2007 to evaluate the effectiveness of several pre-seed burn-off treatments applied at recommended label rates for the control of cleavers at advanced growth stages. The treatments listed below were applied on May 24, 2007 at which time the cleavers had nine whorls and were up to 20 cm tall....
Foxtail Barley (Hordeum jubatum) Control in Wheat and Flax (2006)
Foxtail Barley
Foxtail barley (Hordeum jubatum) a perennial grass native to western North America has increased in relative abundance three and a half fold since 1970 (Leeson et al. 2005). Foxtail barley propagates mainly by seeds and has become a more serious weed problem whenever tillage intensity and frequency is reduced (Moyer et al. 1994) Previous studies have shown that fall applications of glyphosate gave the best control of foxtail barley (Blackshaw et al. 2000). However if the applications did not occur in the fall is early or late spring applications of glyphosate best for control of foxtail barley? In 2005 a trial was established and sulfosulfuron was applied post emergent to all treatments except an untreated check to reduce the impact of new seedlings so we would be able to evaluate the control on the foxtail barley that were there in the spring. After observing the impact of the post emergent treatment to an area outside the trial that did not have a post emergent treatment, in 2006 another factor was included in the experiment. A system approach to control foxtail barley including glyphosate timing and rate and with and without a post emergent application on quizalofop in flax....
Recropping 11 Months after Everest (flucarbazone - sodium) Application (2005)
re-cropping
Everest (flucarbazone-sodium) is a grassy and broadleaf weed control herbicide that is registered for use in spring wheat. Everest enters the plant through foliar and root uptake and is broken down in the soil by microbial activity. It's soil residual properties mean that there are some re-cropping restrictions following its use....
Herbicides for Control of Round-leaved Mallow (Malva rotundifolia) (2003)
Roundleaf mallow
Annual weed introduced from Europe. Cotyledons are distinctly heart-shaped with a round tip. First true leaves are long stalked and round to kidney shaped. Low spreading plant with long branched, hairy stems....
Low Drift Nozzles - How Coarse is Too Coarse? (2002)
Low Drift Nozzles
New "venturi" nozzle technologies that dramatically reduce spray drift were introduced into Canada in 1997. These nozzles incorporate air into the spray pattern, and reduce drift by up to 95%. Since their introduction, ten venturi-type nozzle models have become available and these are very popular with applicators. In 2000, new low-drift nozzles that do not use air-amendment were introduced, and these will likely also have good market potential. Applicators require information on how far they can go towards drift reduction without reducing herbicide efficacy. The need for air-induction must also be objectively assessed....
Interactive Effects of Spray Quality, Air Induction, and Herbicide Mode of Action on Weed Control (2002)
Mode of Action
Low-drift nozzles that emit coarser sprays have become widely available and are very popular with applicators across Canada. Air-induction nozzles use venturis to draw air into the spray, increasing coarseness but also changing droplet behaviour on impaction. There are concerns about weed control with larger droplets, particularly on grassy weeds, have raised questions about the use of such sprays in some situations. The role of air-induction in this regard is unknown.Applicators require information on whether coarse sprays are appropriate in specific weed control situations. The need for air-induction must also be objectively assessed....