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Best Grannom Caddis Pattern: The Green-Assed Walt’s

peeking caddis fly

As much as I am obsessed with the Walt’s Worm, it is only fitting that my list of confidence nymphs includes several variations of this effective pattern. The Green-Assed Walt’s, GAW for short, is a Grannom caddis larva imitation. This pattern was first brought to my attention by my buddy, Grumpy Dave, on a well known freestone creek in Somerset County a few years ago.

Grumpy Dave is an exceptionally talented nymph fisherman that catches more fish than I do in a given session, but that day we were trading fish back and forth. Hammering them! I was using a pink collared Walt’s Worm and asked him what he had on. Yelling downstream, he yammered, “A Green-Assed Walt’s!” At that time, I had no idea what the pattern was, so upon catching up with him, I asked him for one. After a bit of grumbling, he forked several over and I was first introduced to the GAW!

Freshly caught trout
The GAW is an effective pattern for both stocked and wild fish, and is truly one of my favorite caddis patterns to use during when Grannom are most active.

Fishing the Green-Assed Walt's

The GAW is a pattern that I believe was developed by George Daniel, the esteemed competition nymph fisherman from central Pennsylvania. He can be found on YouTube demonstrating how to tie his version, the Peeking Grannom Caddis.

The pattern is intended to be a Grannom cased caddis larva imitation, and it is a damn simple and effective one at that. Grannom cases look like miniature Washington Monuments, or obelisks if geometry class is your fancy, stuck all over the rocks in a stream bed. If you have fished any of the central Pennsylvania limestone spring creeks, then you have surely snagged these industrious little fellas, finding them stuck to the point of your nymph hook. Plucking one from a rock, you will see the bright green larva and his little black head peeking out of the base of the miniature Washington Monument he constructed. And that is the food source that the GAW imitates to near perfection.

This pattern works best in the early spring, from mid-April until about mid-May in Pennsylvania, when the grannoms are active and hatching. During this period of the springtime, if you are a betting person, take the odds to Vegas that I will likely be fishing a GAW.

Tying the Green-Assed Walt's

fly tying supplies

In the past, I have avoided tying cased caddis imitations because they are remarkably complicated with a full grocery list of unnecessary and gaudy materials. That was the case until I discovered the GAW. If you can tie a Walt’s Worm, then you can surely tie this pattern, too.

As all patterns in this article, begin by placing the bead on the hook, wrapping a few turns of lead and lashing it down with a thread base. For the GAW, I prefer a matte black beadhead but have had great success using silver and copper beads, too.

When tying this fly, here is the part where the magic happens, and the one part of this pattern that takes a bit of practice to get right. Take a very liberal clump of Hareline Caddis Green Ice Dub and roll it into a tight noodle between your fingers. Fold this noodle in half and tie it in at the hook bend with the fold hanging off of the back. Take great care to lash down all of the fibers along the top of the hook shank. Next, trim the dubbing fibers off of the back just a bit beyond the hook bend. You have just created the peeking head of the cased Grannom caddis.

tying a fly
The first step to tying the GAW is to secure a clump of Ice Dub in Caddis Green to the hook shank. Trim the fibers so that they stick out approximately 1/4-inch beyond the bend of the hook.

From this point, simply finish the fly by tying a standard Walt’s Worm with a mono or wire rib. I prefer to use Hare’s Ear Plus Dubbing in Dark Hare’s Ear #2, but will also tie this with a dark brown body. The Hare’s Ear Plus Dubbing can be very spiky and hard to wrap a tight body with. Sometimes moistening your fingers can help you twist a tighter dubbing loop. Also, after a couple of wraps up the hook shank, give the dubbing another little twist to secure the noodle on the thread a little better and continue wrapping all the way to the bead. 

After counter wrapping with the mono rib, secure with a whip finishing tool. You can make a few extra wraps to create a little more contrast, but this isn’t really necessary. 

Simplest cased caddis imitation in the history of fly tying, I guarantee it.

fly tying with mono rib
Use Fine/Clear Uni-Mono (or 3x tippet material) and tie in to use as ribbing.
dubbing a fly
Create a dubbing noodle with Dark Hare's Ear #2 and wrap a tight body up the hook shank and secure behind the bead. Next, counter wrap the mono rib over the body and also secure behind the bead.
whip finish fly
Use a whip finisher to crate a thread color behind the bead and finish the fly.
fly in tying vise
The GAW, Green-Assed Walt's, is an effective peeking caddis imitation that is easy to tie and catches lot of fish!

Watch the Tying Tutorial for the Green-Assed Walt's

Did You Find This Fly Tying Guide To be Helpful?

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