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American March Brown Dun

$2.75

SKU: N/A Category:

Hook Size 10/12

I hope you don’t start reading this article about the March Browns if you haven’t read the
nymph and emerger articles because I won’t repeat the previously mentioned concerns
and important points about fishing this hatch. The American March Brown dun is certainly
a beautiful mayfly. It’s so large and colorful that you would think every big trout in the
stream would focus on eating them. The trout do eat the duns. There is no question
about that. Just don’t overlook the nymphs and emergers. They eat far more of them
than the duns.

You want to be aware of the fact that these mayflies will probably be found in different
sizes during the long hatch. They will not vary in size at any one specific time but they will
from the start of the hatch to the end of it. The duns will gradually transgress in sizes
throughout the long hatch period. These mayflies can vary in terms of hook sizes of their
imitations from a 10 to a 12, although most of them will be closer to a size 12.

Presentation:
Most anglers that fish imitations of the March Brown dun just toss them in the fast water
runs and riffles as they progress upstream, unaware of where the March Browns hatch.
To imitate a March Brown dun with the highest odds of success, you need to present the
fly very near the same areas of the water the March Browns hatch. If you are not sure
where they hatch, then I suggest you go back and read the article on the emergers.

Normally, the duns won’t get off the water quick enough to avoid being caught in the fast
currents. It isn’t necessary to allow the fly to drift a long way downstream from the areas
the mayflies likely hatched. The duns usually don’t stay on the water long enough to drift
long distances. Lots of short presentations will usually increase your odds of success.

If possible, you should present the fly with an upstream or up and across cast. You can
get closer to the fish fishing upstream. However, depending on the type of stream your
fishing, you may find that may not be the most productive way to get the fly to a likely
spot. A longer downstream, or down and across presentation, may prove to be the best
way to present the dun imitation.

I’m not getting into presentation techniques. I just want to point out that you need to get
the fly in the area of the fast water immediately adjacent to where the American March
Browns hatch – that is fast moving side of the current seams. If you do that during the
time the March Browns are hatching, you will usually get the type of explosive reaction
that makes dry fly fishing so great.

Copyright 2013 James Marsh

Weight N/A
Hook Size

10, 12