Keep it Clean is reminding Canadian canola, cereal and pulse growers that careful management of preharvest glyphosate applications can help to ensure crops meet the needs of our domestic and export customers. Applying pre-harvest glyphosate too early can result in unacceptable product residues in the grain which can create market risk.
Where allowed, pre-harvest glyphosate should only be applied for weed control once grain moisture is less than 30% in the least mature part of the field. Growers are encouraged to consult the Keep it Clean visual staging guides (links below) to see examples of various crops at less than 30% grain moisture.
Be advised that glyphosate may pose a marketing risk for cereal and pulse crops. Growers should be aware of these considerations for the 2020 growing season:
- Wheat, barley and oats: Some customers have contract limitations on pre-harvest application of glyphosate. Growers are advised to talk to their grain buyer to confirm that an application of pre-harvest glyphosate will not cause concern for domestic or export customers.
- Oats MAY NOT be accepted if treated with pre-harvest glyphosate – growers must always check with their grain buyer before applying.
- Malt barley WILL NOT be accepted if treated with pre-harvest glyphosate.
- Pulses: Growers are advised to consult with their grain buyer before using pre-harvest glyphosate on pulse crops. Some grain buyers may not accept pulse crops treated with preharvest glyphosate due to scrutiny in the global marketplace and low MRLs for some pulse crops in certain major markets.
Please note: There are currently no products of concern for canola; however, producers are reminded to follow the Keep it Clean guidelines to avoid unacceptable residues.
Keep it Clean recommends the following practices to manage the pre-harvest application of glyphosate for canola, pulses and cereals, with the exceptions noted above:
- Glyphosate is registered for pre-harvest weed control and is not to be used as a desiccant.
- Pre-harvest glyphosate should only be applied for weed control once grain moisture is less than 30% in the least mature part of the field.
- To avoid unacceptable residue levels, always follow the product’s label for application rate, timing and pre-harvest interval (PHI).
- Never harvest earlier than recommended – this can increase the risk of excess glyphosate residues in harvested grain.
- When using glyphosate for pre-harvest weed control in a tank mix with other products, such as Saflufenacil (e.g. Kixor®, Heat™), the products must still be applied when grain moisture content is less than 30% in the least mature part of the field and must also follow the PHI of the most restrictive product label.
Source : Keeping it Clean