San Juan Worm

Controversial but effective. Simple chenille worm, deadly after rainstorms.

Printed on the Joker

The San Juan Worm is a short length of red or pink chenille on a hook, and it is the most divisive fly in the sport. Purists dismiss it as bait with a hook in it. Everyone who has fished the San Juan, the Bighorn, or any tailwater in high water knows perfectly well that it works, and works when almost nothing else does.

It is not a trick. Aquatic worms genuinely live in silt and gravel in enormous numbers, and every time flows rise or the riverbed is disturbed they get washed into the drift. Trout eat them eagerly because they are large, soft and defenseless. A drifting red worm is a real and frequent event in a trout's life, not an insult to its intelligence.

Its finest hour is high, off-colored water — spring runoff, a dam release, or the day after heavy rain, when clarity is poor and the fish need something substantial and visible. Under those conditions it is not merely effective; it is often the correct answer.

What does a San Juan Worm imitate?

Aquatic worms.

How do you fish a San Juan Worm?

Dead drift deep under an indicator, usually as the top fly with something smaller trailing. Get it right down on the bottom — worms do not swim.

When should you fish a San Juan Worm?

Year round, and at its very best in high, colored or rising water after rain or a flow change.

What are the quick tips for fishing it?

• Red, pink and wine all have their days; carry more than one.
• The day after heavy rain is San Juan Worm weather.
• Fish it deep. If it is not near the bottom, it is not doing its job.

How is a San Juan Worm tied?

• Hook: curved scud or standard nymph, #10-#16
• Bead: optional, for depth
• Body: red, pink or wine ultra chenille, singed at both ends

Dressings vary by tier and region. Treat this as the common recipe, not the only one.