This is a slight variation of Charlie Craven’s Deep Blue Poison Tung that I’ve found to be remarkably effective during the winter months here in the east. I think individually both white and blue are great colors to incorporate in just about any winter pattern, having them both together in one fly, how can you go wrong?
For a hook, I like a bit smaller than Charlie’s original pattern, here a Dai-Riki #125 Emerger Hook in size 22. Plunger style hackle pliers make handling these little hooks much easier. Start by mashing the barb in the jaws of your tying vise or with needle-nosed pliers.
I usually prefer to keep small flies unweighted, so I’ll use a glass bead rather than a tungsten. These are midge-sized silver and gray with a colored core. Just drag your hook through the herd to impale one. Once you’ve got the bead onto the hook, get the assembly firmly secured in the jaws of your tying vise.
For thread, I’ve loaded a bobbin with a spool of UTC, 70 denier in white. This will be the body color of the fly. Start your thread on the hook shank immediately behind the bead and take wraps rearward before snipping or breaking off the tag.
Extra small Gun Metal Blue Ultra Wire is used to rib the fly and subtly work in the color blue. A 4-5 inch length will make multiple flies. Secure the wire to the top of the hook shank with wraps of tying thread. I didn’t mean to let the wire extend out over the bead, try to have it start right at the back edge. Take nice, even, touching wraps of tying thread to anchor the wire to the top of the hook shank. Keep making these wraps well down into the hook bend. Then, reverse direction and do the same type of wraps back up the hook to right behind the bead.
Get hold of the Ultra Wire and make open spiral wraps up the shank to segment the body of the fly. When you reach the bead, secure the wire with a few tight turns of tying thread. While bracing the hook with the nozzle of your bobbin, helicopter the wire to break it off close.
For the fly’s thorax, I like light gray SLF Prism dubbing because of the way it shimmers and its light blue tint. On a hook this small, you only need the tiniest amount of dubbing. With it, create a slim, short noodle on your tying thread. Take touching wraps with the noodle to build up the fly’s thorax behind the bead. When you’re done, do a 4 or 5 turn whip finish and snip or cut your tying thread free, and that’s all there is to it.
While you’ve got the material out, consider tying a larger, heavily weighted version of the Poison Tung to transport its little brother down to the bottom, where trout tend to hang in the winter. To build a tandem rig that incorporates both flies, I’ll Uni-Knot an 18 to 24 inch length of light, limp mono tippet material to the hook bend of the larger fly and tie the smaller fly to the other end.
There are numerous products out now, specifically designed to hold multi-fly rigs. They can work wonders when it comes to reducing tangles and speeding on-stream rigging - two things that are especially important during the winter months when cold hands do nothing to help with dexterity.
Whether you believe in the magical effect the color blue has on trout or not, the Poison Tung is definitely a fly worth having in your arsenal