The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
In 91 records from GBIF, adults of this species have mostly been collected during June (33%), May (22%), July (20%), and August (12%).
In 59 records from GBIF, this species has been collected at elevations ranging from 39 to 5103 ft, with an average (median) of 1881 ft.
Time of day: Afternoon or evening
The larva builds a retreat, or dwelling tube, by raising a simple roof or a groove in a sunken piece of wood. The tube is camouflaged with pieces of detritus and a layer of silk.