Yes. You may use a treble hook when fishing the Middle Fork of the Salmon River. Just make sure the barbs are removed or completely bent down on all three points. In Idaho the definition of hook is: a bent wire device to which one, two or three points may be attached to a single shank. The same rules apply to all waters in the state that are restricted to barbless hooks. The number of points on the hook doesn't matter as long as the barbs are removed.