They adapt drought. If there is no raining it absorbs underground water a lot so the under ground water decreases.If there is no under ground water they absorb the humidity(the amount of water vapour in the air) from the air surrounding it. We never use these trees' products, morovr its roots change the ground water poisonous. It never shelters birds becausethey produce less oxygen but emits more carbon dioxide. It also affects soil nutrients. It makes it surrounding doughty. It is essential to cut these trees where ever we see.