Pre-Harvest Glyphosate Staging Guide
Pre-Harvest Glyphosate Timing: When to Spray Before Harvest
Use these handy staging guides to determine when grain moisture is less than 30% in your crop, the only stage at which pre‑harvest glyphosate may be applied.
Canola
Cereals
Pulses
Printable Guide
General glyphosate information
Where allowed, glyphosate is registered for pre-harvest weed control only. It is not registered for use as a desiccant.
Pre-harvest glyphosate can only be applied once grain moisture is below 30% in the least mature part of the field, including areas of regrowth that may still produce seed. Applying glyphosate too early can result in unacceptable residue levels in harvested grain.
To reduce residue risk and protect market access:
- Always follow the product label for application rate, timing
,and pre-harvest interval (PHI).
- Never harvest earlier than recommended. Harvesting before the PHI has elapsed increases the risk of unacceptable glyphosate residues.
- When using glyphosate in a tank mix with other products (such as saflufenacil [Heat]), application must still occur at less than 30% grain moisture, and the most restrictive PHI on the tank mix labels must be followed.
On-farm decisions matter. Proper timing helps protect Canada’s reputation as a trusted supplier of high‑quality canola, cereals and pulses. For current product advisories and more ways to keep your crop market ready, visit the Product Advisory page.
FAQs
When can glyphosate be applied before harvest?
Glyphosate may only be applied for pre-harvest weed control after grain moisture is below 30% in the least mature areas of the field. Applications made before this stage increase the risk of unacceptable residues.
How do I determine crop maturity?
Crop maturity is assessed by evaluating grain development and moisture, including late‑maturing plants and regrowth. Staging guides help identify when the crop has reached the appropriate maturity for pre‑harvest glyphosate use.
What happens if glyphosate is applied too early?
Applying glyphosate before the crop reaches the correct maturity can result in unacceptable residue levels in the grain, which may lead to non‑compliance with market and regulatory requirements.
We’re all in
this together.
Do your part to protect the quality and reputation of Canadian crops and help keep markets open for all.
Follow the Keep it Clean 5 Tips to ensure your canola, cereals and pulses are ready for market.