The Complete Handbook of Fishing Yarn

Chapter 1: Understanding Fishing Yarn

Fishing yarn is a bundle of twisted or spun fibers, natural or synthetic, used as the primary building block in many fly patterns. It serves as the body, the wing, the tail, or the head of a fly, replacing the fur, feathers, and hair of classic patterns with something more consistent, uniform, and available. The difference between a fly that looks alive in the water and one that looks like a lump of fuzz is often the specific yarn you chose, how it was made, and how you mounted it on the hook.

To understand fishing yarn, you have to understand the fiber first. Yarn is only as good as what it is made of, and the chemistry of that fiber dictates every important property you will use. The two broad families are natural fibers and synthetic fibers, and they could not behave more differently in the eyes of a fish.

Natural fiber yarns include wool, silk, cotton, and sometimes mohair or angora. Wool is the most common in tying because it absorbs water, which makes it heavy, and because it has a high degree of natural crimp, which traps air and creates a somewhat buggy outline. A wool-bodied fly sinks slower than a bare hook but faster than a dry fly, making it suitable for wet flies and nymphs that fish in the middle of the water column. The downside of wool is that it absorbs the water it is meant to distress, loses