Jim Dennett smacks 'em pretty consistently with a Corky rigged with single hooks. He said he only missed one fish out of fifteen this afternoon. Pretty good hook up ratio if you asked me.
Most fish we have been catching have been in water about this deep, especially with a little sun. By late winter they are pretty much used to colder water, so it takes more to drive them off out of wading range. Keep casting....there's good trout in there with them.