The Grannom (Brachycentrus subnubilus) is one of the first sedges to show up in spring. Its mass hacthes make
it a fly of remarkable importance to fly anglers. The Grannom appears in April (thru June) and the hacthes last
about 10 days.
The Grannom is present in all Europe in big and medium streams.
In the chalk streams, its larvae are often found in huge concentrations. In the english limestone rivers its massive hatches compare
in importance and number to the mayfly (E.danica).
It is a medium size sedge (7-14 mm) and owes its nickname (greentail, french: culvert, german: Grünschwanz) to the typical
emerald green egg sack of the females. This egg sack can be more then half the lenght of the whole abdomen.
The emergence from the water occurs from mid morning
until late afternoon and it causes great excitement among fishes. The
mating "dance" and egg dropping at dusk are also very impressive. Fishermen who witness it can hardly forget the blizzard-like scene of thousends
of sedges flying all over.
It is almost everywhere the first major hatch of the year and if the emerging and egg-laying stadiums bring the trouts
to the surface, the spents produce great fish activity too. In this case the same pattern, used for the adult stage, can help,
simply let it float with the current, without the typical skating used when imitating the emerging or egg laying insect.
