The most well known olive colored fly is probably the blue winged olive, but that pattern only represents Genus Baetis and related mayflies. The olive all-over fly represents those mayflies and many other insects of a similar color that are prevalent in most American waters where trout swim.
Not to be confused with parachute pants, the parachute hackle represents a spent or struggling insect and the bright white post makes the fly easier for the angler to see.
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