Back

Grizzly Half Hackle Mayfly Dun

by @dekasso

Grizzly Half Hackle Mayfly Dun — a fly pattern by Dekasso
More by @dekasso

Half Hackle Dun · Dry fly

A grey sail settling into the film

A half-hackle mayfly dun dry fly in grizzly and grey, size 14, for trout rising to duns on smooth water.

A mayfly dun dry fly with a fan of grizzly hackle standing only above the shank and long split tails. It has a pale grey segmented quill body, a wisp of dun CDC through the hackle and a neat black head.

Pattern
Half Hackle Dun
Imitates
Grey and dun mayfly hatches, typically spring and early-autumn afternoons
Hook
size 14
Tippet
5Xrule of three
  • Hackle above the shank only
  • Dun CDC mixed into the hackle
  • Slim banded grey quill body
  • Long split grizzly tails
  • Size 14 dry fly hook

On the water

A dry fly riding the surface of a trout river

Grizzly hackle fans up like a small grey sail, flecked with soft dun CDC. Below it sits a slim, banded quill body, two long barred tails and a tidy black head behind the bronze hook eye.

Fish it on glides and slow pools when duns are drifting and trout are sipping. With the hackle clipped beneath, the body rides low in the film. Cast upstream of the rise and let it drift drag-free.

Trimming the hackle underneath is the step to get right. Clip the fibers flat along the shank after wrapping, so the fly lands upright and sits its body down on the water.

A coiled leader, tippet spools and an open fly box on slate

Rigging

Tippet
5Xhook size divided by three
Leader
Nine feet, tapered — longer and finer in flat water
  • Use 5X or 6X tippet for a clean, drag-free drift on slick water.
  • Dress the hackle lightly with floatant; keep paste off the CDC, a desiccant powder works better.
  • Cast a short reach upstream of the fish and let the fly drift down to it without twitching.

Where and when

Hatch
Grey and dun mayfly hatches, typically spring and early-autumn afternoons
Target
Trout
Water type
Smooth glides, slow pools and soft seams
Also fishes
Spring creeks, lake margins with calm surfaces and the soft edges of freestone runs during a dun hatch.

Make it yourself

Intermediate5 materials · 10 steps

Pattern
Half Hackle Dun
Style
Dry fly
Hook
Standard dry fly hooksize 14
Thread
Black 8/0
Fly-tying materials laid out on a dark bench

Materials in the order they go on the hook

  1. TailGrizzly hackle fibers
  2. BodyGrey stripped quill
  3. WingNatural dun CDC
  4. HackleGrizzly dry-fly hackle
  5. HeadBlack thread

Details

Imitates
Mayfly Dun
Colors
Grizzly grey, Dun, Pale grey, Black, Bronze
A fly-tying vise holding a bare hook on a wooden bench

How to tie it

The steps, from first wrap to whip finish (10)
  1. Mount the hook and start the black thread behind the eye, then run a thin base back to the bend.
  2. Tie in four grizzly hackle fibers at the bend for the tail, about one shank length long.
  3. Split the tail fibers into two pairs with a figure-eight of thread.
  4. Tie in the stripped quill at the bend and bring the thread forward to the three-quarter point.
  5. Wrap the quill forward in touching turns to show clean bands, then tie off and trim.
  6. Tie in a sparse pinch of dun CDC on top of the thorax, fibers standing upward, and trim the butts.
  7. Prepare a grizzly hackle with fibers about one and a half times the hook gap and tie it in by the stem.
  8. Wrap the hackle forward four or five turns through the CDC, then tie off and trim the tip.
  9. Trim the hackle fibers flat underneath the shank, leaving only the upper half standing.
  10. Build a small, neat black thread head and whip finish.
Proportions (4)
  • Tail: about one shank length, split into two pairs.
  • Body: bend to three-quarters of the shank, slim and evenly banded.
  • Hackle fibers: roughly one and a half times the hook gap.
  • CDC: a sparse pinch, no taller than the hackle.
Tips (3)
  • Soak the stripped quill for a few minutes so it wraps without splitting.
  • Stroke the CDC upward before wrapping the hackle so the two blend into one fan.
  • Use a dark-tipped grizzly feather for the strongest barring in the hackle.
Common mistakes (3)
  • Too much CDC hides the grizzly; use only a few fibers.
  • Cutting the hackle underneath at an angle makes the fly tip; keep the clip flat to the shank.
  • A bulky head crowds the eye; leave room and keep head wraps to a minimum.
A dozen-fly materials kit laid out on slate with its recipe card.
The kit

Every kit size

Materials only

Size 14 · Materials only · 12 flies

$50.75

$4.23 a fly

Includes Standard dry fly hook · and 7 more

Every item in this kit · 8 items

Hooks & beads

  • Standard dry fly hook$6.501 × 25 · size 14

Thread & wire

  • Black 8/0 thread$2.951 spool

Materials

  • Grizzly hackle fibers$11.951 saddle pack
  • Other material: Grey stripped quill$4.501 pack · From the recipe row "Body"
  • Natural dun CDC$6.951 pack
  • Grizzly dry-fly hackle$11.951 saddle pack

Finishing

  • Head cement$5.951 bottle

Guide

  • Printed recipe and tying stepsIncluded1

Size 14 · Materials only · 48 flies

$97.38

$2.03 a fly

Bought separately $102.50 · you save $5.12

Includes Standard dry fly hook · and 7 more

Every item in this kit · 8 items

Hooks & beads

  • Standard dry fly hook$132 × 25 · size 14

Thread & wire

  • Black 8/0 thread$5.902 spools

Materials

  • Grizzly hackle fibers$23.902 saddle packs
  • Other material: Grey stripped quill$92 packs · From the recipe row "Body"
  • Natural dun CDC$20.853 packs
  • Grizzly dry-fly hackle$23.902 saddle packs

Finishing

  • Head cement$5.951 bottle

Guide

  • Printed recipe and tying stepsIncluded1

Size 14 · Materials only · 144 flies

$246.53

$1.71 a fly

Bought separately $280.15 · you save $33.62

Includes Standard dry fly hook · and 7 more

Every item in this kit · 8 items

Hooks & beads

  • Standard dry fly hook$351 × 100 + 2 × 25 · size 14

Thread & wire

  • Black 8/0 thread$17.706 spools

Materials

  • Grizzly hackle fibers$71.706 saddle packs
  • Other material: Grey stripped quill$22.505 packs · From the recipe row "Body"
  • Natural dun CDC$55.608 packs
  • Grizzly dry-fly hackle$71.706 saddle packs

Finishing

  • Head cement$5.951 bottle

Guide

  • Printed recipe and tying stepsIncluded1

With vise & tools

Size 14 · With vise & tools · 12 flies

$200.75

$16.73 a fly

Includes Standard dry fly hook · and 16 more

Every item in this kit · 17 items

Hooks & beads

  • Standard dry fly hook$6.501 × 25 · size 14

Thread & wire

  • Black 8/0 thread$2.951 spool

Materials

  • Grizzly hackle fibers$11.951 saddle pack
  • Other material: Grey stripped quill$4.501 pack · From the recipe row "Body"
  • Natural dun CDC$6.951 pack
  • Grizzly dry-fly hackle$11.951 saddle pack

Finishing

  • Head cement$5.951 bottle

Tools

  • Rotary pedestal vise$791
  • Ceramic bobbin$141
  • Fine-point scissors$161
  • Whip finisher$91
  • Hackle pliers$71
  • Bodkin$51
  • Bobbin threader$41
  • Dubbing wax$41
  • Canvas tool roll$121

Guide

  • Printed recipe and tying stepsIncluded1

Size 14 · With vise & tools · 48 flies

$239.88

$5 a fly

Bought separately $252.50 · you save $12.62

Includes Standard dry fly hook · and 16 more

Every item in this kit · 17 items

Hooks & beads

  • Standard dry fly hook$132 × 25 · size 14

Thread & wire

  • Black 8/0 thread$5.902 spools

Materials

  • Grizzly hackle fibers$23.902 saddle packs
  • Other material: Grey stripped quill$92 packs · From the recipe row "Body"
  • Natural dun CDC$20.853 packs
  • Grizzly dry-fly hackle$23.902 saddle packs

Finishing

  • Head cement$5.951 bottle

Tools

  • Rotary pedestal vise$791
  • Ceramic bobbin$141
  • Fine-point scissors$161
  • Whip finisher$91
  • Hackle pliers$71
  • Bodkin$51
  • Bobbin threader$41
  • Dubbing wax$41
  • Canvas tool roll$121

Guide

  • Printed recipe and tying stepsIncluded1

Size 14 · With vise & tools · 144 flies

$378.53

$2.63 a fly

Bought separately $430.15 · you save $51.62

Includes Standard dry fly hook · and 16 more

Every item in this kit · 17 items

Hooks & beads

  • Standard dry fly hook$351 × 100 + 2 × 25 · size 14

Thread & wire

  • Black 8/0 thread$17.706 spools

Materials

  • Grizzly hackle fibers$71.706 saddle packs
  • Other material: Grey stripped quill$22.505 packs · From the recipe row "Body"
  • Natural dun CDC$55.608 packs
  • Grizzly dry-fly hackle$71.706 saddle packs

Finishing

  • Head cement$5.951 bottle

Tools

  • Rotary pedestal vise$791
  • Ceramic bobbin$141
  • Fine-point scissors$161
  • Whip finisher$91
  • Hackle pliers$71
  • Bodkin$51
  • Bobbin threader$41
  • Dubbing wax$41
  • Canvas tool roll$121

Guide

  • Printed recipe and tying stepsIncluded1

The creator

An illustrated portrait for Dekasso (an illustration, not a photograph)

Dekasso

@dekasso

Wherever the truck rolls to a stop.

  • Tidewater Sundown Pale Ale — a river beer by Dekasso
  • Prairie Wildflower Portrait Trucker Hat — a trucker hat by Dekasso
  • Ember Golden Stonefly Nymph — a fly pattern by Dekasso

See everything by @dekasso

How it was made

2 iterations led here; the saved one is marked

  1. Iteration 1 of 21
  2. Iteration 2 of 22 Saved

Remixes

Remixed from

  1. Slate Ledge Grizzly Soft Hackle — a fly pattern by DekassoSlate Ledge Grizzly Soft Hackle@dekasso · the original
  2. Grizzly Half Hackle Mayfly Dunyou are here

1 remix of this

Evening Ember Sulphur Mayfly Dun — a fly pattern by Dekasso@dekasso

Where this came from

“make it half hackle such that there is only hackle above hook. mix in just a little cdc into the top hackle”

fly pattern · made

1 remix

25 — from 1 remix, at the Derby's published weights, since . Views are not counted.

  • dry fly
  • mayfly
  • dun
  • half hackle
  • grizzly
  • cdc
  • quill body
  • trout
  • size 14
  • grey