I've been blessed to fish for trout with dry flies on some of the top streams and rivers in the country, from the Bow River in Alberta to the Big Horn in Montana. Over those decades of angling, several hatches have stood out for providing spectacular fishing.
The two at the very top of the list are the Blue Winged Olive and Tricorythodes. And it's a delight to say that you can still find these two insects emerging heavily on many trout streams throughout the country, including local waters such as Mossy Creek near Harrisonburg.
• Blue Winged Olive: When my mind drifts back to memorable hatches I've fished, none can compare with the tiny Blue-Winged Olive or Baetis mayflies. There were days when the Olives emerged so heartily that trout fishing dreams became reality. I even fished a tremendous grayling rise once on a plunging northern Saskatchewan river where the smoky-winged Olives emerged by the thousands on a cold, shower-swept day.
And that's another thing that makes fishing this hatch such an intense experience. They often emerge heaviest and draw the strongest feeding from trout when the air is leaden and showers spit from the sky or winter snowflakes rush sideways through the air.
The flies can emerge virtually any month, and I've fished them on Pennsylvania's limestone streams often on frigid winter days. Spring can be even better, but fall is also a great time to find Olives hatching.
Often they overshadow more heralded hatches, such as Hendricksons. You can find them on neutral pH streams, but they do best in alkaline waters. Spring creeks and tailwaters are prime. Areas with vegetation and shallow gravel runs are especially good.
Sizes of the various members of this genus can range from 4 mm to 10 mm, matched by hook sizes 14 to 24. The most common sizes are 16-20.
As far as time of day, mid-afternoon is the best period to find olives hatching. Look for them when the water temperature is in the upper 40's to low 50's. A traditional pattern will work, but I've had better luck with thorax, parachute, Comparadun and no-hackle dressings. The bodies of these flies can range from bright olive to a dark, grayish brown. You can tie a variety of colors to match these various shades, or simply blend all three colors of rabbit fur into an amalgam that works well for all Baetis hatches. Wings should be medium to dark gray.
Nymph and dun fishing may last several hours, but spinner falls can also provide excellent fishing. Use a rusty brown-colored body with light to medium gray clipped hackles or polypropylene wings to imitate these mating insects. They generally return to the stream from late afternoon into early evening.
• Trico: The name of this second fly is a shortened version of its Latin name, Tricorythodes. Few other emergences can match the intensity or reliability of this tiny black and white mayfly for summer fly fishing sport. Millions of the duns emerge early in the day, followed by stunning spinner flights at mid-morning.
But while the fishing during this hatch is excellent, it is also immensely challenging. The reason for the difficulty is the tiny size of the insect and the abundance of naturals on the water making it less likely that the trout will key in on your imitation floating amid thousands of real bugs.
The Trico measures a mere 3-4 millimeters. Size 22-26 hooks are appropriate. This makes it tough to see the fly and sometimes difficult to hook fish when they sip in your offering, because of so little gap in the hook. But the intensity of the trout's feeding on these insects makes up for that by giving you plenty of chances.
Be sure to study the rhythm of the fish's feeding pattern. You want your fly to drift over the trout just as it's ready to rise. Use a 3 or 4 weight rod, 12-15 foot leader and 6x or 7x tippet.
For duns a parachute or Thorax tie is best. Most of the action will center on spinner fishing as the mating insects swarm over the water with their tiny glassine wings sparkling in the morning sunlight. Riffles and pools directly below them are particularly good areas.
A rabbit or mole fur body with split hackle tails and polypropylene spent wings is the best pattern. Males have all-black bodies. Females have a black thorax and whitish abdomen.
For those of us with declining eyesight, seeing these flies on the water can be difficult. Try painting a bright fluorescent orange dot on the top of the fly where the fish can't see it but you can.
If hooking fish is a problem, try using the multiple-fly. Trout sometimes grab two or three Tricos at once. In certain cases you can have success using a size 16 or 18 hook with two or three sets of bodies and wings tied on the shank, to simulate a cluster of flies floating downstream.
Award-winning outdoors writer Gerald Almy is a Maurertown resident.