Although my Wind Rivers experience is small compared to W-D's, I've been chomped on by both horseflies and deerflies there. It does make a difference if you're well away from trails getting frequent horse use! A warm sunny day with no wind along the Fremont Trail is time to put on medieval armor, or at least a good wind shirt!

Permethrin works on ticks and mosquitoes, but not biting flies. They bite right through my permethrin-sprayed shirt as though it were an appetizer!

I also remember the black flies in June in northern Michigan! While visiting there, one afternoon I ended up putting Hysson in the car, blowing out the flies, then closing up the car and driving around the area running the air conditioner until dark. We got up before daylight the next morning and got out of there (Porcupine Mts.) before the flies showed up!

Unfortunately, I'm one of those people whom Heather likes to bring along on trips!