Cecil, I'm not sure, my dad did the mixing and we made 55 gallons of spray. He hit the cattails from the shore the day before when I was gone, the next day we hit them from the pond side with my bass boat. If I remember right he had two cups of surfactent and then we added another two cups of regular dishwashing soap to the mix. All soaps are a surfactent as they help break the surface tension of water.
We will probably have to hit the cattails again in 3-4 weeks, they are a very hardy plant.
