Yep! You will find both is the short answer.
The sow bugs are there in decent numbers, but they tend to be quite small and are hardly ever seen out from under their rocks! Since there’s not tons of vegetation, like the limestone Ozark streams, they are not a primary food source.
The mayflies and Caddis are WAY more important, with stoneflies and midges coming in next.
That’s not to say sow bug and scud patterns won’t be useable. Just not my first choices…
