The trick is to walk as far from access points as possible.then stay out of water as much as possible.then use big nymphs and accurate casts to lies. If you can stand as far away as possible so they cannot see you. Buggers work well down there as do prince nymphs. A hopper with a small dropper will work too. Don't overlook any water. The smallest riffles can make for good fishing. Deep holes hold the bigger ones mostly near trees and high banks.