One of the first flies that can be seen on the rivers or our lakes is the Stone Fly or its correct name Plecoptera.It is recognised by its roof shaped wings and is usually seen climbing up reeds or grasses on the margins of the lake or river to hatch into an adult fly.

It is seen in several colours ,from Black to Salmon to Orange. Trout usually do not get the chance to feed on the nymphs as they are found under the stones and then fairly close in to the banks where they can climb up the reeds and grasses to emerge as adult flies.

The adult female flies would fly back to the river, deposit their eggs, and die as they floated downstream. Fishing for trout would be frantic!As to the size of fly needed to represent them I think a size 6 or 8. I also reckon that there is no need to use an accurate imitation and a fly pattern as shown below on the right would work wonders.

Suggested materals for tying this fly. Body stripped peacock herl ,coloured with waterproof marker pen. Enclosed wing of Antron dubbing. Head of peacock sword herl. The mobility of the wing material is key to this fly.

References : Nymphing A Basic Book by Gary A Borger