McALESTER — Is it too late to apply glyphosate herbicide for winter annual weed control in bermudagrass?
Glyphosate, the active ingredient in the popular herbicide product Roundup and certain similar products, can sometimes be used over completely dormant bermudagrass for winter-annual grass control and broadleaf weed control.
But, how do you know if it is too late in spring to effectively use a glyphosate containing herbicide for weed control without damaging your bermudagrass? You have to scout the area to make sure conditions are still suitable for this application!
Excerpt from Roundup Pro label: “Dormant Turfgrass — This product may be used to control or suppress many winter annual weeds and tall fescue for effective release of dormant bermudagrass turf. Treat only when turf is dormant and prior to spring green-up.”
Here is a good tip for successfully using the glyphosate application over dormant bermudagrass while minimizing risk of bermudagrass injury: Walk over the bermudagrass stand and closely observe from just above the bermudagrass leaf canopy to ensure the stand is totally dormant and that no live bermudagrass shoots are popping through the canopy! If you see no live tissue through the tan canopy, you are good to spray.
The application is best made when temperatures are in the 60s but definitely prior to bermudagrass green-up. By the time air temperatures are in the 60s, winter annual weeds are generally metabolically active and are more effectively controlled by this application.
For more information on lawn weed control contact your local OSU Extension Office.
David Cantrell is the agriculture Extension educator for Pittsburg County. Contact him at 918-423-4120.