Eradicating Tall Wheat Grass - Ask Extension
Tall Wheat Grass is over taking our irrigated pasture competing with Fescue's and Orchard Grass and more. We have used a " Whicker" with ov...
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Eradicating Tall Wheat Grass #867061
Asked May 04, 2024, 9:20 PM EDT
Tall Wheat Grass is over taking our irrigated pasture competing with Fescue's and Orchard Grass and more. We have used a " Whicker" with over 120 OZ of Round Up multiple times and no success. Is there a chemical that kills the Wheat Gene in Tall Wheat Grass and will not harm to other grasses.
Sherman County Oregon
Expert Response
Mike,
Unfortunately there are not alternative herbicides to use that would hurt the tall wheatgrass while not injuring your other desired cool season grasses in your hay field. I spent a good hour looking into alternatives that you might be able to use and I cannot find any that are selective on specific cool season perennial grasses over other cool seasons grasses for you to use in a broadcast herbicide application.
Tall wheatgrass is a hard one to treat as it grows tall and skinny - hard to get chemical to stick to enough effective surface area, especially with a wick applicator. The wick applicator is however probably the best option. If the tall wheat grass is throughout the entire pasture than spot spraying sounds too time intensive.
Are you using a good surfactant, such as a non ionic surfactant, with the herbicide to help it stick? They suggest not using MSO with glyphosate. I assume that you probably are already, but that could really make a difference with a wick application. Also sounds like you are using a high concentration, which is what you should do with a wick applicator.
Application timing could also make a difference, applying when the plant is actively growing is best, especially right before the grass is flowering in the spring.
I wonder if a drone could detect the taller Tall Wheatgrass in the field over the other grasses? AgCopter might be able to map the taller plants with a drone that you could then put into your sprayer on a usb thumb drive. This is assuming that you have a sprayer with individual nozzle or section control - section control would kill some desired species with the wheatgrass though. I am wondering if the wick applicator just isn't getting enough coverage on the plant to be effective despite the higher concentration? You could also go out there with a backpack sprayer and spray glyphosate where you see the plants. This would be more time intensive though.
There is also a chance that if you have been using glyphosate for several years in this field that there may be some plants that are resistant to glyphosate. Poast Plus Herbicide and Pursuit are some herbicides used in hay crops that could also work if glyphosate resistance is an issue. Glyphosate is probably the best option to use though. I am not a fan of promoting the use of paraquat, but that is another non selective alternative that could be used with a wick applicator, though it is restricted use and will require a pesticide license and the online paraquat training. You could also use other non selective herbicides with the wick applicator.
Feel free to contact me at<personal data hidden> or email me at <personal data hidden>.
Unfortunately there are not alternative herbicides to use that would hurt the tall wheatgrass while not injuring your other desired cool season grasses in your hay field. I spent a good hour looking into alternatives that you might be able to use and I cannot find any that are selective on specific cool season perennial grasses over other cool seasons grasses for you to use in a broadcast herbicide application.
Tall wheatgrass is a hard one to treat as it grows tall and skinny - hard to get chemical to stick to enough effective surface area, especially with a wick applicator. The wick applicator is however probably the best option. If the tall wheat grass is throughout the entire pasture than spot spraying sounds too time intensive.
Are you using a good surfactant, such as a non ionic surfactant, with the herbicide to help it stick? They suggest not using MSO with glyphosate. I assume that you probably are already, but that could really make a difference with a wick application. Also sounds like you are using a high concentration, which is what you should do with a wick applicator.
Application timing could also make a difference, applying when the plant is actively growing is best, especially right before the grass is flowering in the spring.
I wonder if a drone could detect the taller Tall Wheatgrass in the field over the other grasses? AgCopter might be able to map the taller plants with a drone that you could then put into your sprayer on a usb thumb drive. This is assuming that you have a sprayer with individual nozzle or section control - section control would kill some desired species with the wheatgrass though. I am wondering if the wick applicator just isn't getting enough coverage on the plant to be effective despite the higher concentration? You could also go out there with a backpack sprayer and spray glyphosate where you see the plants. This would be more time intensive though.
There is also a chance that if you have been using glyphosate for several years in this field that there may be some plants that are resistant to glyphosate. Poast Plus Herbicide and Pursuit are some herbicides used in hay crops that could also work if glyphosate resistance is an issue. Glyphosate is probably the best option to use though. I am not a fan of promoting the use of paraquat, but that is another non selective alternative that could be used with a wick applicator, though it is restricted use and will require a pesticide license and the online paraquat training. You could also use other non selective herbicides with the wick applicator.
Feel free to contact me at<personal data hidden> or email me at <personal data hidden>.
