Grannom
The Grannom is the first significant caddis hatch of the season, appearing in April on cold chalk streams and freestone rivers alike. Traditional patterns use a brown body — but the key insight is that during emergence, the Grannom's body is bright green with thin black segmentation; it only turns brown after the fly has been airborne. Trout feeding during the hatch are targeting the green-bodied emerger, not the spent adult. Fish it on the surface in current seams and riffle edges.
- Type
- dry fly (Caddis)
- Hook sizes
- #14–16
- Target species
- trout
- Difficulty
- intermediate
- Best seasons
- spring
Materials
- hook: Dry fly hook #14–16
- thread: Black 8/0
- body: Green seal's fur (green highlander shade)
- ribbing: Black tying silk, well waxed and doubled
- wing: 3–4 dark CDC plumes, trimmed to hook bend
- hackle: Red game genetic cock, 3–4 turns, wound in front of wing
Tying steps
- Mount a size 14–16 dry fly hook; start black thread at the bend.
- Dub a bright green body of seal's fur (green highlander shade) from bend to the 2/3 mark.
- Wind doubled black waxed silk thread in 5 tight spirals over the body as segmentation ribbing.
- Select 3–4 dark CDC plumes; tie them flat over the body as a tent wing reaching to the hook bend.
- Trim CDC tips flush with the hook bend.
- Wind 3–4 turns of red game genetic hackle in front of the wing.
- Build a small black head; whip finish and cement.
- Inspect the tent wing from above — it should form a symmetrical inverted V, lying flat over the body with both halves equal in width and slightly raised at a 30-degree angle.