Updated October 15, 2026
    dry

    Borcher's Drake

    Imitates isonychia (Slate Drake) Mayfly

    Hal Borcher's Isonychia drake imitation. An important late-season hatch in Michigan and Eastern rivers.

    Tie it yourself

    Hook sizes

    #10#12#14

    in brown, gray

    Type
    dry
    Imitates
    Isonychia (Slate Drake) Mayfly
    Difficulty
    intermediate
    Technique
    dry fly drift, hatch matching
    Water
    freestone

    Tie it yourself

    When to fish it

    Late summer through fall during Isonychia (Slate Drake) hatches.

    Trout

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    Read before you go

    Gear & tipsFly Tying EssentialsTools Materials & First Patterns to Learn
    Gear & tips

    Fly Tying Essentials – Tools Materials & First Patterns to Learn

    Master fly tying fundamentals with essential tools, materials, and beginner patterns that catch fish consistently.

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