September Fly Selection - Dynamite Terrestrial Fishing
By JD Miller

Carl's Cicada from Umpqua Feather Merchants


  • Yellow Triple Decker Hopper, size 8
  • Beetle, size 14
  • South Fork Chernobyl, size 10
  • Carl's Cicada, size 8

I think September is the best month of the year to fish in the West because the crowds are lighter, the weather is great, and the dry fly fishing fantastic. There are numerous hatches during the month that bring the fish to the surface, but the real draw during this time is the terrestrial fishing that draws large trout to the top with vicious strikes. While terrestrial fishing usually begins around the middle of July on most rivers, the best time to fish these bug is the first couple of weeks of September. Cooler nights help keep the water temps low so the fish stay active throughout the day, yet the days are warm enough to keep the insects active for extended periods of time; exposing them to hungry fish that are starting to stock up calories for winter.

While trout do take terrestrials throughout the day, the best times to fish these patterns are from late morning through early evening; the warmest parts of the day. During this time, I like to start the morning stripping streamers or fishing nymphs until the sun really hits the water sometime around 10:30am. At that time, I will switch over grasshopper or beetle pattern and fish with it until the sun dips back below the horizon the day gives way to evening.

Hoppers and crickets can range in size from as big as a size 2 down to a size 14, with 6-10 being the most common. As with most other insects, they usually diminish in size as the season progresses. The key to fishing terrestrials successfully is to keep them close to the banks, usually no more than 5' off. The fish will be looking for these insects when the wind blows them off streamside vegetation and overhanging trees, not out in the middle of a run 30' from the bank. Because of the often viscous strikes, I like to use 4x or heavier tippet. In extremely flat water or with very spooky fish, you can drop down to 5x but you have to be extremely careful on the hook set when you do this.

Another key to successful terrestrial fishing is to keep moving. In most cases, the fish will take your offering within 2-4 drifts if it is interested. Do not keep working the same pool, or the same fish, over and over again. Make 3-4 casts, and then take a couple of steps up/down stream. I like to cover LOTS of water when terrestrial fishing. Sometimes, imparting a little action in the fly will draw a strike-Just as the fly hits the water, give the fly a short, quick tug to push a little water and give the rubber legs action. Also, delicate presentations are usually not needed as these bugs make a splash when they hit the water.
Of all the terrestrials available to trout, grasshoppers are especially hardy-I sometimes think they are made of anti-freeze! Most anglers stop fishing the bugs after the first hard freeze of the fall, but I'm telling you that is a mistake! Their activity window during the day may decrease as the days cool, but they will remain active during the warmest hours and continue to be a food source for trout well into late fall. I've caught trout on hopper patterns as late as November, so don't dismiss them after a little cold weather.

Terrestrials are a favorite food source for trout, so they will draw fish to the surface on any body of water where they are found. However, the North Platte River in North Park, the Eagle River near Gypsum, and the Rio Grande River near Creede are all excellent spots to throw terrestrials this month.

See you on the water!