The March Brown fly pattern is a classic and effective imitation of the March Brown mayfly, making it indispensable during spring hatches. It's designed to mimic the natural insect's size, color, and movement, making it highly attractive to trout. This fly is best used in moderate to fast-moving waters where March Brown mayflies are known to hatch, typically in the afternoon. A dead drift presentation, occasionally twitched to suggest a struggling mayfly, can provoke aggressive strikes from feeding fish, capitalizing on their natural feeding habits.