Yellow May Dunn
- Hook: Dry fly – size #14
- Thread: 8/0 yellow uni-thread or equivalent
- Tail: Yellow feather fibres
- Body: Number 47 fly-rite or any dry fly dubbing coloured bright yellow
- Wing: Mallard silver flank feather dyed yellow
- Hackle: Sunburst yellow cock hackle.
- Tie in the thread and run it down the hook with touching turns. Take the thread back up the hook.
- Leaving sufficient space for a head, take a mallard flank feather and tie it in by the but. Split the feather at the point and pull back the two halves and tie in to form the wings.
- Run the thread back down the hook and tie in some mallard feather fibres to make a tail.
- Dub the thread and wind this along the hook shank leaving space for a collar hackle behind the wings.
- Tie in the hackle feather and make a collar hackle around the wings.
- Take the thread up to the eye and make a head, whip finish and then varnish.
The yellow May dun (Heptagenia sulphurea) is quite a common species and can be found hatching in large numbers, early season, on most rivers including the Usk where it is very prolific and taken by trout. The hatch on the Usk can last for several weeks.
This pattern was shown to me by Mark Roberts.