Now that harvest activities are starting to wrap up some producers are thinking about post-harvest weed control.
One of the biggest post-harvest weed control issues tends to be Canada Thistle.
John Ippolito - a Regional Forage Specialist with Saskatchewan’s Ministry of Agriculture - says the requirement for regrowth after harvest is likely the biggest concern with this year’s dry conditions.
He says the plants should be allowed to regrow until there is at least eight inches of new growth prior to a herbicide application:
"In most cases glyphosate will be the herbicide of choice for control of Canada Thistle in a post-harvest application."
Glyphosate rates required for post-harvest application are essentially double the recommended pre-harvest rates. There is also a requirement for a frost free period after the application.
Ippolito says for best control the plants should still be actively growing:
"Is there regrowth up above the stubble? Also now that we've had a couple of lighter frosts, we also have to evaluate what the frost damage to those leaves has been. We still need good, viable green leaves that aren't turning brown around the edges and getting brittle on us."
Source : Discoverestevan