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Spraying Weeds After Frost And Snow

When freezing temperatures stop fall weed control plans, snow is likely more of a help than a hindrance with respect to overall weed condition. The snow layer is likely to insulate the weed leaf material from the colder conditions that follow it. That could mean you’re back spraying earlier than you would be with frost alone. Spray decisions — when to spray or whether to spray at all — will depend on leaf condition after the snow is gone.
 
Does herbicide work better after a frost? No. While cooler temperatures with daytime highs in the mid to high teens do increase movement of sugar, and with it glyphosate, to the roots of perennial weeds like Canada thistle, frost does not enhance that movement. In fact, research reports that a light frost following a week or more of “hardening” at alternating 15°C and 5°C temperatures had no effect on movement of glyphosate or control of Canada thistle. However, while frost doesn’t improve control, it may not necessarily reduce control if enough healthy tissue remains to allow sufficient uptake of the herbicide.
 
Spraying after a frost. Killing frost for weeds is hard to define since so many factors influence it. Different plants have different inherent tolerance to frost. For example, stinkweed can germinate in fall and survive the winter to grow the following year whereas a wild mustard plant will not. Weather preceding the frost may also affect frost tolerance. A Canada thistle plant that has had little exposure to cooler temperatures may be susceptible to a frost of as little as -3 to -4°C, whereas a plant that has gradually acclimatized to cooler conditions and progressively deeper frosts may survive a frost of -10°C or more. This is why it is critical to continually check the condition of leaf tissues before filling the sprayer.
 
If weeds are green and the leaf tissue is still relatively pliable, growers may still have an opportunity to control perennial weeds with glyphosate. To determine whether spraying after a frost is worthwhile, scout the field and check the amount of damage on the leaves. Control can still be obtained if no more than 40% of the original leaf tissue is damaged.
 
But remember…because the amount of leaf area after harvest is only one third of what was there before harvest, even with several weeks of regrowth, using the same amount of glyphosate as in a pre-harvest application will not be effective. In reverse proportion to the leaf area, at least three times the rate used at the pre-harvest timing will be needed to get the same level of glyphosate into the plant.
 
When scouting to determine the value of post harvest weed control, consider…
 
—Are there enough weeds to warrant a spray?
 
—Are they winter annuals or perennials? Fall is a good time to hit perennials, biennials and winter annuals. On annuals: Spraying annuals in the fall can be worthwhile if it looks like they’ll produce mature seeds before freeze up. If annuals have already set seed, it may be better to save the burnoff for next spring when those seeds emerge. (NOTE: Research out of southern Alberta suggests that kochia regrowing after a mid-August harvest will not produce seed before a killing frost in most years. If using glyphosate to control those annual weeds, you may simply be adding additional selection pressure for the development of glyphosate resistance.)
 
—Are weeds actively growing?
 
—Is frost damage less than 40% of the leaf tissue?
 
If these conditions exist, then a fall herbicide treatment may be of benefit.
 
Tip: Even though cool weather may trigger perennials to start moving sugars downward, you still want to apply glyphosate and Group 2 herbicides on sunny and warm days for best results.
 
Source : CanolaCouncilCanada

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The FCDC and AgSmart Bring Plant Breeding to a Wider Audience

Video: The FCDC and AgSmart Bring Plant Breeding to a Wider Audience

In the vast prairies of Alberta, Olds College’s Field Crop Development Centre (FCDC) stands as a beacon of innovation and research in the agricultural world. The institution has become a key player in advancing agricultural technologies and practices. The FCDC’s commitment to applied research has driven them to seek effective means of disseminating their findings and creating a positive impact on the farming community.

One such avenue that aligns with their mission is AgSmart, an event dedicated to showcasing cutting-edge agricultural technologies. The coming together of the FCDC’s annual Field Day and Ag Smart has proved to be a natural fit, fostering a synergy that benefits both parties and propels the agriculture industry forward. The FCDC Field Day took part in conjunction with AgSmart for the first time this week on Aug. 1-2 in Olds, Alta. FCDC Program Director Kofi Agblor and Olds College VP of Development Todd Ormann sat down for an interview with Marc Zienkiewicz to discuss the significance of the two events taking part together and what the future holds.

The Intersection of Research and Technology The essence of the FCDC lies in its dedication to plant breeding and new seed varieties, particularly barley and triticale. While conducting research is essential, it becomes meaningful when its benefits are shared with the wider community. This is where AgSmart steps in, providing a key venue for the FCDC to showcase their research. This union between research and technology creates a holistic and enriching experience for farmers, ranchers, and industry professionals, the pair said.

Seeds as Technology For the FCDC, the partnership with AgSmart goes beyond mere event collaboration. It is about creating an environment that bridges the gap between seeds and smart technology, Ormann said. The college believes that for technology to truly revolutionize agriculture, it must begin with a strong foundation — high-quality seeds. As the saying goes, “it all starts with a seed.” To demonstrate this critical aspect, the collaboration aims to showcase the seed value chain as an integral part of the smartphone.

The Birth of a Powerful Alliance The idea of joining forces emerged when staff realized the potential synergy between AgSmart and the FCDC Field Day. With just a few days separating the two events, a proposal was put forward to merge them. The marketing and communications teams from both sides worked seamlessly to ensure the essence of both events remained intact, creating a powerful alliance that leverages the strengths of each, Agblor said.

Driving Advancements in Breeding For Agblor, the partnership with AgSmart has tremendous potential to drive advancements in breeding and other technology. With technologies like drones and imaging becoming integral to phenotyping, breeding is no longer confined to vast fields to assess thousands of plants manually. Instead, it benefits from the data-rich insights brought about by smart technologies. These advancements make breeding more efficient, precise, and instrumental in shaping the future of agriculture.

Overcoming Challenges Together While the partnership between Olds College and Ag Smart has been a resounding success, there are challenges on the horizon. Securing stable funding for long-term breeding initiatives is crucial to sustain progress. The college is committed to navigating these challenges and investing in agriculture’s future sustainably, Agblor said.