THE GREAT OUTDOORS — With spring comes the arrival of the first major aquatic insect hatches of the year — mayflies and stoneflies. These bugs mark the beginning of "dry fly season" across the West, and offer a relief to anglers everywhere who've spent most of winter nymphing for lethargic trout or throwing tiny size 26 midges at wary tailwater fish.

So with dry fly season fast approaching, these are the fly patterns every angler needs in their box to have a successful day on the water.

The venerable PMD =================

The PMD, or pale morning dun, is one of the most effective mayfly patterns in the world. While spring is often dominated by the blue-winged olive mayfly, PMDs can also be seen on some western waters. In addition, they help "unmatch the hatch" when you find yourself in the midst of a blanket blue-winged olive hatch, like we see on Utah's own Green River.

BWOs sizes 16-22 ================

This is the main bug hatch that really gets fish going after a long winter. Once the days get longer and the water warms up just a tad, blue-winged olive mayflies will hatch on nearly every Western water — and especially those in Utah. I was on the Middle Provo River last Sunday and spent three hours throwing BWOs to picky brown trout. Leaving home without at least a dozen BWOs during this time of year just isn't a wise idea.

Stonefly nymphs ===============

Next to the BWO, stoneflies are the other main spring hatch. The Lower Provo River sees a skwala hatch (a species of stonefly) in the early months of the year, and other waters around the state will have their dose of early-season stonefly hatches. The pattern you'll need specifically is the golden stonefly.

Both the nymph and adult version of the golden stone are important to have in your box, as a lot of the larger trout will be more apt to eating a nymph as opposed to a dry fly.

Ginger quills =============

These flies are a personal favorite of mine for two reasons: they're incredibly simple to tie (thanks in large part to Hareline Dubbing's new synthetic quills) and work wonders as a general mayfly imitation. As mentioned above, the most common mayfly to hatch is the BWO, but other mayflies will be present, and the ginger quill can imitate all of them.

Tied catskill style with extra-long hackle, the quill also serves well as an indicator fly when fishing a dry-dropper rig. The larger sizes of the ginger quills can even be mistaken for adult stoneflies by some trout.

Adult stoneflies

With the main early-season stonefly being the golden stone, it's important to have a few of the adults in your box. But, as with mayflies, you may run into a skwala hatch, or other type of stonefly. It's almost impossible to predict whatyou'll find when out on the water.

A great pattern to use that imitates a variety of adult stoneflies is the oft-overlooked Picket Pin. An older pattern, it's rarely seen for sale in fly shops, which means that most trout haven't seen it. The fly is bushy, floats high in the water, and looks just buggy enough to fool most trout into thinking it's a proper adult stonefly.

While you can certainly stuff your box with more than the flies mentioned aboved, these are the ones that I've found most effective while spring fishing in the Beehive State. Mayflies are a must and stoneflies are always good insurance on the chance you run into a partiuclarly great hatch. As the prolific Patrick F. McManus wrote, "What a tourist terms a plague of insects, the fly fisher calls a great hatch."

What are your favorite spring fly patterns? Let us know in the comments.

Spencer is a fly fishing writer based in Utah. A member of the Outdoor Writers Association of America, he's a columnist for the Standard-Examiner, KSL.com, Fishwest, and Trout Life. Find him on Twitter or Instagram, @Spencer_Durrant.

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