Producers can ensure the chemical sprayed on their canola or pulses won’t leave unacceptable residues by adhering to the pre-harvest interval — or PHI — found on the product’s label.
Often referred to as the “spray to swath” interval, the PHI is the number of days that must pass between spraying pesticides or desiccants and swathing/straight cutting.
The PHI can vary greatly between products — from one day to more than 60 days — so it’s important that producers know and adhere to the prescribed interval for each product applied to a crop. This ensures the product’s active ingredient has had enough time to break down in the plant.
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Growers can plan their pre-harvest spraying with an interactive Spray to Swath Interval Calculator.
To calculate how long to wait after spraying before heading out to swath or straight cut, select crop type and then the product (from the pull-down menu). Along with the minimum number of days before a crop can be cut, the online tool provides relevant information or warnings, if applicable.
The tool can also be used to select a product to fit a specific timeline. It is also mobile friendly.