John from Gambier, Ohio writes
Grass Out Max (Clethodim Herbicide) is only labeled for tall fescue in prairie grasses and would not be recommended for treating Reed Canary grass. Unfortunately, a lot of the products specifically labeled for pastures are essentially non selective products which will require direct spot treatments to the canary grass directly.
Roundup Custom Aquatic Terrestrial Herbicide is labeled for Reed Canary grass at the rate of 1.5 to 2.3 quarts per acre or 1 fl oz per gallon of water, 1.5 pts per 25 gallons of water. If this prairie pasture is used for grazing, there are no restrictions for livestock or grazing animals when applied at rates below 4.5 pints per acre. Please view the full product label for more information.
Answer last updated on: 10/24/2024