Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.
These are pretty much always called Stripetails and Yellow Stones.
This is a very common trout stream stonefly genus. It is also huge, with sixty species scattered over the entire continent. Though anglers usually call them Little Yellow Stones or Yellow Sallies, the scientific common name for this genus is Stripetail. The latter is probably better to use as not all of them are necessarily little or yellow.