All of our HT is a single strand 28-32 inches high. For gates w use a single strand of HT with a gate handle at the charger end. That way the gate serves as a switch and won;t arc when it's laying on the ground with the gate open. If it's in a place that the gate will normally be open and you want power past it all the time, I bury a double insulated wire and hook the hit wire to it. The gate then is insulated at the end away from the handle. Not very good as explaining it easier to show it in about 5 seconds.
We use the same setup around ponds.