How to Tie an Isonychia Harrop’s Hairwing

Producer: Tim Flagler

This is an isonychia-flavored Harrop’s Hairwing. Think of a Harrop’s Hairwing as a style of fly, not just an individual pattern. Simply by changing the colors of materials and hook sizes, you can make any number of mayfly imitations.

This isonychia version starts with a nice, big size 10 Lightning Strike DF1 dry fly hook. Make sure to get the hook firmly secured in the jaws of your tying vise.

For thread, UTC 70 Denier in black works well and, on this larger hook, you can even bump up to 140 if you like. Get the thread started on the hook shank, leaving an eye-length space behind the eye and, after taking a few wraps rearward, snip off the excess tag. End with your tying thread about 1/3 of the way down the hook shank.

Moose body hair is used to create a stiff, somewhat buoyant tail on the fly. Snip just a dozen or so hairs free from down close to the hide. Strip out the lower, fluffy fibers and short hairs. Give the clump an ample stacking, then remove it from the stacker with the tips pointed to the rear of the fly. Measure to form a tail a hook shank in length, then transfer that measurement rearward to the start of the bend. Take wraps of tying thread to firmly anchor the hair to the hook shank, all the way back to the bend. Reposition your thread forward to the 1/3 point on the shank. Lift the butt ends of the hair up and snip them off at a shallow angle.

Fine & Dry isonychia-colored dubbing is used to form the body of the fly. I prefer the UV stuff to the regular, because it has a little more shimmer. Pull a small clump free from the packet and use it to create a slender 2” long noodle on your tying thread. Do your best to keep the noodle nice and thin. Start taking wraps with the noodle so the dubbing begins right at the base of the tail. Keep making touching wraps up the hook shank to create a nicely tapered body on the fly, that ends a full two eye-lengths behind the back edge of the hook eye.

For hackle, you can go with a basic medium-dun color, but I really like the natural look of this barred dun, which has shades of brown and tan mixed in as well. Measure to find a feather with fibers of the correct length, here, size 10. Once you’re sure of the measurement, pluck the feather free from the skin. With the shiny side of the feather facing you, strip off the lower, webby fibers from both sides of the stem. Then strip a few more from the top side. Trim the stem off, leaving about 1/8” that’s been stripped on both sides. Lay that portion of stem against the near side of the hook and take tight wraps of tying thread to firmly anchor it there. The stem is likely slippery and you don’t want it pulling out.

Go back to the isonychia dubbing and pluck just a small amount from the packet. Use it to, once again, create a very slender noodle on your tying thread, but this time just a little more than an inch in length. Take wraps with the noodle to build up a slightly bulbous thorax on the fly. End with bare tying thread a full hook-eye length back from the back edge of the hook eye.

Get hold of the feather’s tip with hackle pliers and start making slightly open spiral wraps with the feather up the shank, 4 or 5 turns should be plenty. When you reach your tying thread, use it to anchor the feather’s tip then snip the excess off close. If you have any errant, forward-pointing fibers, pull them rearward and use thread wraps to hold them back, or simply trim them off. In preparation for tying in the deer hair wing, take wraps of tying thread to smooth out the area behind the hook eye.

Comparadun or short, fine dun-colored deer hair is used to form the wing and the head of the fly. Snip a small clump free from the hide and, as you did with the moose body hair, first get rid of the underfur then give the clump an ample stacking. Here, too, remove the clump with the tips pointing toward the rear of the fly. Measure to form a wing that extends to the back edge of the dubbed body. While keeping this measurement, re-grip the clump in the fingers of your left hand. Reach in with your tying scissors and snip the butt ends of the hair off, even with the front edge of the hook eye. Give your bobbin a good counterclockwise spin, as if you’re looking down on it. This will reverse cord the thread and help the first wrap to jump rearward and catch the very butt ends of the hair.

Make two loose wraps with your tying thread around the hair, then pull down to seat it on top of the hook shank. Take one or two more thread wraps at this location, then bring your tying thread under and around to the back edge of the hook eye. Pick up your whip finish tool and use it to do a 4 or 5 turn whip finish behind the eye, seat the knot well and snip or cut your tying thread free. Trim the hackle on the underside of the fly to help it ride flush in the water’s surface. A drop of head cement, here, Sally Hansen Hard as Nails, applied to the thread wraps on the underside of the hook will ensure they don’t come unraveled, and will also help to keep the deer hair wing centered on top of the hook.

And that’s a Harrop’s Hairwing-style Isonychia. Although this fly can be fished at any time of the day, I find it especially effective right at or even after dark.