Randall from Wautoma, Wisconsin writes
How much Tordon per gallon of water?
Tordon RTU is a Ready To Use herbicide and should not be diluted with water. This product is not labeled to control barberry, and it also should not be used in residential areas. The active ingredient in Tordon RTU has an extremely long half-life and, therefore, it can remain active in the area for years after application. To control a shrub like barberry, you would probably need to cut the shrubs down and treat the fresh cuts with a brush killer such as Fertilome Brush and Stump Killer directly to the fresh cuts.
Answer last updated on: 06/02/2019