Dry · #23 of 129

Sulphur Dun

Also known as: Sulphur, Pale Evening Dun, PED

Imitates: Sulphur mayfly dun (Ephemerella invaria, E. dorothea)

Best Sizes: #14-18
Best Season: Mid-May through July — the East's most beloved hatch
Best Conditions: Cloudy late afternoons and evenings on Eastern limestone streams and freestoners
Water Temp: 55-65°F
Recommended Tippet: 5X-6X nylon (for soft presentation)

How to Rig It

Single dry fly on a long leader, 9-12ft. No dropper during a Sulphur hatch — it spooks fish.

How to Present It

Drag-free drift to a sipping fish. Cast 3-4 feet upstream of the rise ring; let it drift naturally. Sulphur sippers are precise eaters.

Why It Works

Sulphurs hatch in massive numbers on Eastern tailwaters and limestone creeks (Penns, Yellow Breeches, Delaware). The pale yellow body and dun wings are an exact match — fish lock on hard.

History

Originally a Catskill-school pattern refined on Pennsylvania's limestoners by Vince Marinaro and Charlie Fox. Today it's the signature hatch from PA to NY to the Smokies.

Pro Tip

Carry both the dun (#16) and a Sulphur emerger (#18) — fish often switch from one to the other within minutes of the hatch peaking.

Frequently Asked Questions

Where are Sulphur hatches found?+

Primarily East and Midwest U.S. — Pennsylvania (Penns, Spring Creek), New York (Delaware, Beaverkill), and Appalachian tailwaters. Rare out West.

What's the difference between a Sulphur and a PMD?+

They're sister species. PMDs (Western, Ephemerella excrucians) run paler yellow; Sulphurs (Eastern) trend more orange-yellow. Patterns are interchangeable in #16-18.

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