Twenty Incher
The Twenty Incher is a big western stonefly and attractor nymph with pheasant tail, peacock, and a bright wingcase, built for fast water and large trout. It fits Twenty Incher nymph, 20 Incher fly pattern, big stonefly nymph, and best anchor nymph for trout.
Imitates: Stonefly nymphs and large mayfly nymphs
Quick Reference
- Best Sizes
- #8-14
- Best Season
- Year-round, strongest spring runoff through summer
- Best Conditions
- Fast riffles, pocket water, deep runs, and high-gradient freestones
- Water Temp
- 38-62°F
- Recommended Tippet
- 3X-5X
How to Rig It
Use as a heavy point fly with a smaller mayfly or midge dropper.
How to Present It
Keep it near bottom with short, controlled drifts through heavy water.
Why It Works
It has the size, weight, and buggy materials needed to get noticed in fast trout water.
History
A Rocky Mountain staple, the Twenty Incher earned its name by consistently moving large trout.
Pro Tip
When flows rise, go bigger instead of smaller. A #8 Twenty Incher can save a muddy day.
Frequently Asked Questions
Is the Twenty Incher a stonefly?+
It is usually fished as a stonefly or large attractor nymph, though it can also suggest big mayflies.
Not sure if Twenty Incher is right today?
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