Canadian canola growers are advised not to use the herbicide quinclorac on their canola in 2016 because China, one of Canada’s biggest customers, has not yet approved it.
“Until these questions are resolved, growers should use other options to control cleavers on their farms,” the Canola Council of Canada says on its website.
“It’s a very serious issue,” council president Patti Miller added in a news release issued by BASF. “Our export customers test shipments regularly to make sure their standards are met and the tests are becoming more and more precise. If a shipment is turned back because of an unacceptable residue, it can mean millions and millions of dollars, not only to the exporting company, but to farm revenue.”
Three herbicides containing quinclorac have been registered for use on canola in Canada — Clever by Productierra, Facet from BASF and Masterline Quinclorac, a Univar product. They all control cleavers.
“If growers have used quinclorac on their canola in 2015, they should contact their local elevator or processor to discuss options,” the council’s website says.
Data from 2015 confirmed that quinclorac leaves detectable residues on canola seed and in the the processed oil and meal, the canola council says.
“When samples were tested from canola fields that had been treated with quinclorac according to label directions, residues were found most of the time. Therefore, the value chain believes there is a significant risk to Chinese exports if quinclorac is used on canola.”
China, which buys about one-third of Canada’s canola exports, has no maximum residue limit (MRL) for quinclorac on canola and no history of accepting imports of canola where the presence of quinclorac residues has been detected. There is also no MRL for quinclorac in the CODEX Alimentarius, the international standard-setting body of the World Health Organization and the Food and Agriculture Organization of the United Nations, which is considered by Chinese authorities in assessing whether imported products meet Chinese requirements, the council says.
“It’s a market where we need to proceed very cautiously,” Brian Innes, the council’s vice-president of government relations, said in an interview.
“This growing season, we have a very strong commitment from members of the value chain to be very clear with growers about what’s accepted and what’s not.”
In December, Japan approved MRLs for quinclorac and China is expected to do so by 2018, Innes said.
“I can assure you the value chain does want farmers to have access to new tools but to do so in a way that protects our export customers,” he said.
Canola is the top revenue-generating crop in Canada, contributing $19.3 billion to the economy annually. It creates almost 250,000 jobs, according to a study prepared for the council in 2013.
About half of Canada’s canola production is exported as seed, oil and meal, with 90 per cent of it going to four countries — the United States, China, Japan and Mexico. The United States is the biggest customer with imports in 2014 worth $3.5 billion, followed by China at $2.3 billion and Japan and Mexico at $1.2 billion and $772,400, respectively. However, China was the top seed importer at 4.3 million tonnes.
There aren’t a lot of good short-term options for controlling cleavers in canola, said Jeanette Gaultier, a weed specialist with Manitoba’s Agriculture Department. The first thing is to scout for the weed both in the fall and spring.
“If it comes up in the fall you’re going to want to control it in the fall,” said Gaultier.
Glyphosate can be tank mixed with several other herbicides to control cleavers. However, be aware that many cleavers are resistant to Group 2 herbicides.
Also, glyphosate shouldn’t be applied alone because cleavers are thought to be prone to developing glyphosate resistance.
“So you definitely want to be looking at different modes of actions,” Gaultier said. “Maybe some Group 4s. The Distinct mix, a Group 19, can also offer some control.
“Tillage is a double-edged sword. Sometimes it can break up plants that are there, but it can also stimulate germination of seeds in the seed bank. Crop rotation is probably one of the best things. It can be a problem in crops that aren’t very competitive or in crops that don’t have a lot of herbicide options. Cereals, and winter cereals especially, throwing those into the mix is a good longer-term strategy for dealing with cleavers.”