Like I said, the label may say 2 hours, but I've always found the longer it sits, the higher % kill I am able to obtain. With 24 hours to sit, I can get almost complete control. With 8 hours, still got very good kills. With only 4 hours, start to notice a difference. Within two hours, I've wasted my time and money. Any glyphosate that washes off is wasted, because it has very, very little residual soil activity. This is especially so when tank mixed with ammonium sulfate.

I have no clue what type of surfactant is used in this particular label. When I mix a tank, I do use a surfactant that costs around $80/gallon. Same stuff I use when spraying undesirable brush with much costlier chemicals, such as triclopry, clopyralid, and picloram.