The PMD Parachute imitates the Pale Morning Dun (Ephemerella), one of the steadiest summer mayfly hatches on Western trout streams and spring creeks. The parachute build - hackle wound horizontally around a single upright post - sits the body down in the surface film instead of perched on hackle tips, so it reads like a real dun riding the water. The post also makes it easy to track in glare and broken light.
Tie or buy it in pale yellow, sizes 14-18. Match the hook to the naturals on the water that day: 16 covers most PMD hatches, drop to 18 when fish refuse, go 14 on bigger duns.
Fish it during the PMD emergence, usually late morning into early afternoon when water sits in the 54-64F range. It wants low to normal flows and clear to lightly stained water - this is a flat-water, sipping-rise fly, not a fast-pocket pattern. Cast up and across and give it a clean dead-drift; the smallest amount of drag puts these trout off. If fish flash at it but will not commit, swap to an emerger or a sparkle dun trailing in the film.