The CDC Caddis Emerger in olive is a fish catcher. During caddis hatches when trout appear to be eating flies with all the might inside them, they are often chasing emergers. The moment between swimming to the surface and taking flight is the sweet spot for this pattern. Attach this fly with light tippet behind a high floating dry fly and create a dead drift with twitches here and there. Because of the small window trout have to capture these bugs before they take flight, the bite is often fast and strong.