Above photo:  March Brown CDC loop wing emerger tied on a #16 TMC 206 BL Around the end of November, I am already planning out my early spring fly boxes, and when I think of spring, I think of March Browns, Hendrickson hatches, and early little stoneflies. My loop wing emergers  are well underway for next year, and I always start with March Browns. Stenonema Vicarium are aggressive mayflies that are very athletic to say the least. They draw slashing rises, even midair assaults from both Rainbows and Browns on occasion. Because the water in the early part of the spring can be discolored and murky, I specifically tie using a small amount of UV fibers, typically paired with Beaver Belly or Awesome Possum. Using  Kapok for the sub-thorax as a very buoyant life jacket makes for a great floater. On my mayfly emergers specifically, I use cream antron for trailing shucks or tails instead of barred wood duck or flank fiber...