A wayleave is a right of way (ROW) over the land of another. This ROW is for carrying Electricity power line through lands.
Vegetation trimming is done to maintain safe clearance from power lines.
Depend upon the voltage of the conductor, safety clearance varies. Typical values are as follows.
1. From 33 kV Power Line - 30 feet
2. From 11 kV Power Line- 15 feet
3. From 400 V power Line- 5 feet