Dave - as with aquatics, the "best" brush control products will vary depending upon several variables. TORDON 22K and REMEDY are two of the best foliar brush treatment products around. REMEDY may also be mixed with diesel and applied to the trunks of targeted brush/woody plants and obtain a very high level of root control. So, the questions to you would be: soil type? adjacent crops? target-plant/tree height and density? any other targeted species besides post oak? are you licensed? etc. etc.
Regarding surfactants: CocaCola? Definitely no. Dish washing soap? Use it only if you don't have access to, or ran out of a commercially produced surfactant that is designed for herbicide treatments.


Kelly Duffie
Cypress, TX