A small creek feeding a brook. On water this size, cover decides most things. Where the banks are open, trout see you coming across the grass; where growth overhangs the water, fish have somewhere to sit and food drops in.
In our experience, rainbows in a creek like this hold in the deeper water: the head of a pool where the run tips in, the seam beside faster current, an undercut bank, the slack behind a log or boulder. Shallow, even-bottomed stretches hold fewer fish and spook them first.