As most growers and industry stakeholders have already heard, reports of glyphosate and glufosinate shortages have become common since late 2021. They have led to bulletins of $100 price increases. 300% for glyphosate in some regions, and recommendations on how to manage their herbicide programs for 2022.
One of the reasons for the reduced supply in North America was due to the effect of Hurricane Ida late last summer. Another is the availability of herbicidal active ingredients from China. Whatever the reason, retailers in Eastern Canada are struggling to stock up on glyphosate, raising concerns that some growers are trying to stockpile the herbicide, which can only drive up prices.
A central Ontario input retailer received their batch of glyphosate last December, and it was far less than expected. Agronomy staff have developed recommendations for low rate applications (using Roundup’s 540 g/L product) in the 0.7-0.8 L/ac. range, instead of 1.0 or 1.5 or even 2.0 L/ac. The recommendations are based on plot trials which determined that the lower rates would reduce glyphosate use by 38% while covering the same number of acres.
In addition to lowering rates, staff advised growers to use a newer, more efficient water conditioner. Tank mixing with another active ingredient is also recommended, as are standard practices: selecting the correct nozzles, correct water volumes, starting when weeds are small and tank mixing glyphosate for residual weed control. weeds.
Several weed scientists and specialists have repeatedly stated that it is still possible to achieve excellent weed control with existing products, even against resistant biotypes of Canada fleabane and water hemp.
Advice from advisors
Three advisors provided their insights on how growers can better manage weeds with less product:
Jonathan ZettlerFieldwalker Agronomy
While the current situation is unfortunate, it could cause growers to revisit products they haven’t looked at recently, working to determine the cost-benefit ratio of their weed spectrum, says Jonathan Zettler, an advisor in culture certified (CCA). Herbicide-resistant Canada fleabane has opened the eyes of some consultants and farmers to the fact that Roundup systems may not be the solution. Instead of doing what is simple, they will have to deepen their knowledge of all the options available.
“Glyphosate is still a very effective herbicide, so if you start cutting rates or not applying it, you better understand your weed spectrum and the limitations of whatever herbicide you’re considering,” Zettler says. . “Some farmers and advisors may only be familiar with Roundup systems and therefore need to learn more conventional chemicals.”
The biggest challenge in moving away from glyphosate is its effectiveness on grassy weeds in corn. In soybeans, post-emergent glyphosate still provides broadleaf weed control at a cost-effective rate. Where there aren’t as many options is with burndown applications in spring or fall, depending on cropping restrictions and weed spectrum. This is where glyphosate remains key.
“So yes, there are some options, both for corn and soybeans, where having a strong pre-emergence program in place from the start is perhaps the best course of action for weed control. annual herbs,” says Zettler. “Understand that the best return on investment in weed control is usually the most effective herbicide to control the biggest yield stealer in your weed spectrum.”
For growers of non-GMO, identity-preserved soybeans or edible beans, there are also crop quality issues such as eastern nightshade. According to Zettler, determining the most effective product to protect yield and operational efficiency is important, not just calculating the cost of production. He suggests that some growers may not understand the impacts of weed stage and density on their production costs.
Zettler says there have been signs over the past year with shortages or delays on winter wheat herbicides and he believes farmers and their retail channels were ready to consider more proactive ways. to solve the expected problems.
“Some growers didn’t change their rates when formulations went from 1.0 to 0.67 L/ac. as the standard control rate. This may be an opportunity for some operations to fine-tune spray rates. »
Colin SmithAndermatt Canada
For Smith, weed management in the event of a shortage of a particular herbicide is not a complex problem. Yes, growers need to understand the weed spectrum on their land and yes, knowing the price of chemicals is vital. But too often, growers and agronomists opt for the cheapest option and sacrifice the best choice for control, possibly allowing a key yield thief to escape, negating any saving in input costs.
“More growers need to understand the mode of action as well as the growth characteristics of the targeted weeds,” says Smith, Andermatt’s sales and marketing manager. “This understanding should determine the best configuration for the application, such as water flow, nozzle selection and nozzle placement. There are new nozzles and configurations that could have a significant impact on control, especially if we go back to chemicals that require more target contact.
As for the multitude of suitable alternatives for effective weed management, Smith notes that there is some reluctance to use older products that may require more tank mixing or a different application schedule. The ease of use of glyphosate-tolerant cultivation technologies is what growers and agronomists have grown accustomed to with unique one- or two-pass chemistry. And that must change. Smith likens it to understanding the value of the cost of production.
“I would like to see more growers looking at true COP per bushel,” he says. “Spreading costs over more acres doesn’t mean COP goes down, especially if yields aren’t as robust. I’ve worked with growers who had higher equipment, fertilizer, and crop protection costs per acre, but their cost per bushel produced is significantly lower.
Smith adds that reduced tagging rates are a reasonable expectation, according to weed pressure. But reducing rates below label specifications presents a challenge, as the label is considered a legal document in Canada. Those who are accredited are expected to follow the label or face a potential loss of their credentials (producers can charge lower rates if they think it’s reasonable). Smith’s experience showed a short-term benefit from lowering tag rates, but it also meant higher costs as weed pressure increased in subsequent crops.
“The key is for growers to realize that there are no magic conventional or organic products that will directly replace all current inputs that are in short supply,” he says. “Organic products require the support of technical expertise, like all products, in order for growers to understand how an organic product works…farmers have become reluctant to enter this group of products due to past history – they tend to be over-promised without tech support.”
In time, the reluctance will disappear as more and more growers succeed in incorporating these products into the appropriate applications.
Paul Sullivan, PT Sullivan Agro
Trying to keep it simple is a common refrain in Eastern Canada. One-pass weed control is what growers and custom spray operators want, says Paul Sullivan of PT Sullivan Agro. His recommendation to circumvent any glyphosate shortage is a solid pre-emergence program with a full rate of a herbicide like Acuron (with rates that are specific to soil texture). With this, he says, there is no need to re-spray the crop with glyphosate.
“In corn, Halex has been a mainstay for a lot of acres in Ontario,” says Sullivan. “A soil-applied herbicide like Integrity or Engarde can be applied pre-emergence, but they are part of a two-pass program, due to timing and the impact of weather conditions. But certainly there are several options using different chemistries.
The cost of poor weed control — as pointed out by Peter Sikkema of the University of Guelph’s Ridgetown campus — is in yield losses. In corn or soy, these can vary between 30 and 40 bu./ac. range, which can be considerable at any time, but especially when commodity prices are relatively high.
When discussions turn to cutting rates, Sullivan thinks many growers apply an appropriate rate for the size and type of weed. Scouting and timing of application become very important, but should be done with greater consideration to the spectrum and size of weeds in any field.
“Weeds will always evolve – they just do that,” he adds. “If you use less than a residual herbicide program, you’ll start pushing pigweed or crabgrass.”