Which method is used to aid the sinking of herbicides in flowing water?

In aquatic pest management, trailing hoses are specifically designed to aid the sinking of herbicides in flowing water. This method involves using hoses that deliver the herbicide directly below the water surface, which is effective in turbulent water conditions. By minimizing the mixing of the herbicide with the water column, trailing hoses help ensure that the herbicide is delivered to the intended target area without being carried away quickly by the flow of water.

While special herbicide formulations can play a role in how effectively a herbicide works, they don't specifically address the challenge of sinking the herbicide in flowing water. Increased contact time is important for the effectiveness of herbicides, but without the proper delivery method, achieving that contact time in flowing water may not be feasible. Sequential applications may be a strategy used to manage aquatic vegetation over time, but they do not directly assist with the sinking of herbicides in a flowing environment. Therefore, using trailing hoses is the most effective method among the options provided for ensuring that herbicides reach their target area in flowing water systems.