Dry FliesJacobpattern
Jaap van der Heijden's Jacob Pattern is tied tiny, down to a #28, with a fine peacock herl body ribbed in holographic silver tinsel and a grizzly cock hackle for flotation. The rib's flash gives an otherwise simple peacock-and-hackle dry extra sparkle for picking out a tiny mayfly or caddis among naturals.
Spring, Summer, Fall
Intermediate
Trout
Feb 2026
Overview
Built down to size #20-28, this pattern targets the smallest mayfly and caddis hatches, where trout often key on tiny naturals and refuse anything oversized. The holographic tinsel rib is a small but deliberate departure from a plain peacock herl body, adding just enough flash to help anglers track the fly on the water. Grizzly hackle keeps the tiny hook riding well without adding bulk. It's worth carrying for late-season technical hatches on both rivers and stillwaters when standard peacock patterns aren't drawing looks.
Where to Buy This Fly
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Materials
- Hook:
- Dry fly hook #20-28
- Thread:
- Benecchi 12/0, black
- Hackle:
- Whiting cock, grizzly
- Body:
- Peacock herl, fine
- Rib:
- Holographic silver tinsel
Behavior & Presentation
Natural Behavior: Adult caddis rest on the surface film between ovipositing runs, wings folded tent-like while drifting in slower currents near eddies and banks. Trout sip these resting insects leisurely because they represent low-energy feeding opportunities in concentrated drift lines that funnel multiple insects past holding stations.
Where Trout Eat It: Trout sip resting caddis adults in European stream eddies near banks, targeting tent-winged insects after ovipositing.
How to Fish It: Maintain long European-style leader drift, relying on unique wing configuration for visibility in slow bank eddies.
Best Water: Target bank-side eddies with gentle back-current, slow drift lines adjacent to main flow, and foam accumulation zones.
Strike Type: The unique wing configuration creates a distinctive silhouette that produces confident sipping rises in slow bank eddies. Strikes appear as gentle surface dimples during prolonged drifts through European-style dead-drift presentations.
Fishing Strategy
Rigging Suggestions: Fish on 10-14 foot leader with 4X-5X tippet. European dry fly approach emphasizes long leaders and delicate presentation for natural drift.
Seasonal Timing: Most effective during hatches April through June and activity July through August when water temperatures range 50-65°F. European dry fly techniques work best during morning and evening feeding periods.
Pro Tips: Unique wing configuration provides visibility while maintaining clean profile. The durable construction withstands extended use through multiple fish, making it practical choice for full-day fishing sessions.
Entomology
Adult caddis rest on the surface film between ovipositing runs, wings folded tent-like over their backs while drifting in slower currents near eddies and banks. Trout sip these resting insects leisurely because they represent low-energy feeding opportunities that require minimal effort, and the concentrated drift lines funnel multiple insects past holding stations.
- Order
- Trichoptera
- Common Name
- Caddisfly
- Organism Type
- insect
- Life Stage
- adult
