When you hook a large trout on Armstrong, Nelsons, or the Letort, it often tries to dive into the aquatic grass in the stream.
My first goal is to get downstream of the trout, even if this requires that I run down the stream bank. Once I’m in this position, I quickly crank in all of the slack fly line and put the trout on the reel. This achieves two important things.
1. It recovers any slack fly line from the stream that could possibly get wrapped around the grass.
2. It puts me in direct contact with the trout so I can control any run he makes.
I keep a gentle steady pressure on the trout with the rod at a low angle, almost parallel to the water because I’ve found that by applying a strong uplifting rod pressure on the trout often prompts him to dive deeply into the grass.
There are many grass tunnels in these streams with wide openings at the downstream end. Hooked trout often run upstream into these tunnels to seek safety. If I apply excessive pressure the trout often dives deeper or wraps the leader to the side in the grass and breaks off. A better ploy is to apply a very gentle rod-pressure directly from below where the trout entered the grass. In this way the trout must fight both the force of the stream and the rod pressure.
It is amazing how quickly this ploy will subdue very large trout.