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Green Rock Worm
A nymph, tied #10–14, carried year round. It is tied against 2 named insects in this book — April–October.
- #10–14Hook size
- nymphType
- AllSeason
- 2Hatches matched
What it looks like
A drawing, not a photograph, and not traced from one. Its proportions were read off 5 independent reference photographs of the pattern and written down as 5 measured characteristics — wing angle, tail length against the shank, how far a hackle fibre reaches — every one of which had to hold across more than one of them before it could be drawn. What survives across many photographs of a fly is the fly.
What it imitates
Each of these is the same hatch record the app's own panel reads, so a pattern recommended on a river card in the app is recommended for one of the insects below.
- Green Rock Worm / Green Weenie Rhyacophila spp. · April–June and September–October · 45–68°F · #10–14
- Green Sedge Rhyacophila spp. · May–August · 48–64°F · #12–16
Tying recipe
In tying order. This dressing is the standard one — these patterns have been in the publicrecord for decades — and materials substitute freely: the proportions and the silhouette are the pattern, not the brand of dubbing.
| Hook | Curved caddis hook, sizes 10–14 |
|---|---|
| Thread | Olive 8/0 |
| Body | Bright insect-green dubbing or vinyl rib, segmented |
| Head | Black dubbing or tungsten bead |
| Rib | Fine clear mono |
| Weight | Lead-free wire, generously |
When to fish it
Dead-drift on the bottom, tight-line. Heavier than a Green Weenie on purpose — the natural is on the rock, not in the middle of the water column.
Carried all year. The insects it matches are active april–october, in water from 45°F to 68°F.
Target species
- Trout
Rivers it fishes well
Rivers with a page here that sit in the regions where the insects this pattern imitates are recorded. It is a claim about coverage, not a report of a fish caught.
- Au Sable River northern lower Michigan · July mean 72.1°F
- Catawba River the North Carolina mountains · July mean 76.7°F
- Jackson River the Virginia mountains · July mean 66.3°F
- Muskegon River northern lower Michigan · July mean 71.0°F
- Escanaba River the Upper Peninsula · July mean 68.3°F
- Saint Croix River northern Wisconsin · July mean 77.2°F
- Smith River the Virginia mountains · July mean 51.9°F
- Tygart Valley River the Virginia mountains · July mean 74.6°F
- Aaron Creek the North Carolina mountains · July mean 76.7°F
- Aaron Run the Virginia mountains · July mean 77.1°F
- Aarons Run the Virginia mountains · July mean 74.2°F
- Abb Run the Virginia mountains · July mean 77.1°F
Related patterns
Same type of fly, or tied for the same insects.
- Green Caddis Larva nymph · #12–16 — Bright green free-living larva. In the drift twelve months a year.
- Green Weenie nymph · #12–16 — Chartreuse chenille. Appalachian brook-trout water does not have a better fly in June.
- Perdigon nymph · #14–20 — Slim, epoxied, sinks like a stone. The euro-nymphing point fly.
- Prince Nymph nymph · #10–18 — An attractor nymph with biot wings. Nobody agrees what it imitates and it does not matter.
- Walt's Worm nymph · #12–18 — Dubbing on a hook. Suggests cranefly larvae, sowbugs and everything else pale and wriggling.