The Wulff series of fly patterns were developed by Lee Wulff. It presents a bushy, high floating fly, that remains visible into the evening twilight, and rides well in rough water. Bucktail is sometimes a better choice for the tail material, because of the "low spin" factor. I always use dark "high on the back"  West Virginia deer hair for the winging material.. I've used this fly with good success on the Elk and other C&R streams. It's an easy tie and floats like a battle ship. Give it a try.