When you find yourself fishing a stream or lake with trees and bushes close behind, the best way to cast a fly rod is by a method known as the roll cast. This is a form of casting that doesn’t involve a back cast. Casting a fly rod using the roll cast keeps your fly and line in front of you instead of behind where it can end up in a tree limb beyond your reach. It’s really hard to catch fish up a tree, but I’m first to admit that I’ve tried many times.
The secret to being able to cast a fly rod by using the roll cast is allowing the tension of the line on top of the water to load your rod for the next cast. Remember that with the overhead cast, it is the back cast that loads the rod.
Start by taking slack out of the line so it’s straight out from the rod tip. Instead of raising your rod high to lift the line off the water, aim the rod at the line and with a steady motion, retrieve the line across the water as your rod arm goes back with the rod lower to the water than on an overhead back cast. When the leader and about ten feet of fly line are all that are still on the water, forcefully flick the rod forward to create a round loop that will send the line and leader out in front so as to cast the fly to where you’re aiming. Once you get the feel of it you’ll be surprised at how far you can cast. If you’re fishing a stream with a good current, another tip is to allow the line to straighten out as it drifts downstream. Then retrieve some of the line before pulling it in with your arm motion to load your rod for the roll cast. On smaller streams I use the roll cast for almost all casts. Here’s a great video demonstrating this technique of casting: