Spruce Moth
Imitates: Adult spruce moth (Choristoneura) and large tan caddis
Quick Reference
- Best Sizes
- #10-14
- Best Season
- Mid-July through August
- Best Conditions
- Western freestone rivers near spruce/fir forests, broken water, banks, evening rises
- Water Temp
- 50-68°F
- Recommended Tippet
- 4X mono
How to Rig It
Fish alone during a spruce moth event, or as the dry in a hopper-dropper rig in mid-to-late summer in moth country.
How to Present It
Dead-drift along banks and under overhanging trees where moths fall in. Skating and twitching also work well — these moths flutter actively on the water.
Why It Works
The tan elk hair downwing perfectly matches the silhouette of a real spruce moth on the water, and the palmered hackle keeps it floating high in fast Western currents.
History
Spruce moth hatches periodically explode on Western rivers like the Madison, Big Hole, and Rock Creek, drawing some of the biggest trout of the year to the surface during a normally tough mid-summer window.
Pro Tip
If you are fishing a Western river in late July or August and the rises don't match any obvious mayfly or caddis, look up at the trees. A spruce moth event can be one of the best dry-fly weeks of the year.
Frequently Asked Questions
What is a spruce moth?+
It is a small tan-colored moth whose larvae feed on spruce and fir trees. Adults often get blown onto Western rivers in huge numbers in mid-to-late summer.
Why fish a moth instead of a caddis?+
During a spruce moth event, trout key specifically on the slightly larger, paler moth silhouette and often refuse standard caddis patterns.
Not sure if Spruce Moth is right today?
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