I pre-package all of my double knotted hopper legs because I size
them for both adults and juveniles, each package contains
enough legs for two hoppers. (x4 legs per juvy hopper)
One of the most distinguishing characteristics of the grasshoppers geometry is its hind legs or “jumping legs”. These legs are often over dramatized or under dramatized in many patterns. Many of the pre-knotted legs we get from catalogs or fly shops are pre-knotted legs made from several hackle fibers of pheasant tail. Often these look like bottle brushes or the business end of a broom. If you look closely at a juvenile grasshoppers legs they are fairly slender and are most definitely tapered. By taking just two hackle fibers of a pheasant tail and tying a half hitch at the very end of the fibers and a second half hitch in the middle of the fibers you get two joint sections in a single leg. (as seen in the anatomical diagram below and the above photo)
Again you can see that the taper is very narrow at the last joint. So the pre-knotted pheasant tail legs sold commercially are far from accurate and also very wind resistant. These larger pre-knotted legs can potentially influence the trouts take and the hook set because they are fairly stiff throughout the length. The geometry of the hind legs in reality is much more refined. I use four to six legs on my patterns. In general I have found that using just two fibers of pheasant tail per leg is adequate for both adults and juveniles. You can adjust the two half hitch distances for larger adult legs as well.
Knotting your own hopper legs is easy and although more time consuming is a cheaper and more convincing solution for your favorite hopper patterns.