The tricky bit about the easemnet is that it is city property/homeowners responsibility. It is our civic duty to keep it mowed and presentable- but whatever is in it is actually city property. i.e. if there is a tree already there- you cant cut it down- its city property. If they want to plant a tree there- they can plant anything they want. If they are not planting trees there and you want a tree there- get permission (from the city and the utilities) but buy it yourself. If they decide they want to do something different with the easement, they can tear out whatever you have done and do it. Which is why most of us dont. It just happens that the city is not currently doing anything to our easemnets- but if it came to that, they could rip out his stuff- or order him to. I wouldnt have spent my money to landscape city property- honestly.