Strange right!! How can a tree gets poisoned? Well here, Tree refers to human nature or human body or well can say tree like human being for a reference. For example : roots of a trees refers to human legs , and branches here refers to hands , well the above parts of tree so called leaves and fruits part refers to the Human Mind. let me now go to depth for a deep understanding . Roots are one of the greatest part of tree. Roots are main core of Tree. The only difference between Roots and Human legs is that mobility i.e Roots cant move and legs can travel entire world. Human creatures are superior here because our legs can move. We can walk, run, jump and can do many more things. If we go further roots turns into branches which is middle section of the Tree. Branches provides fruits, leaves, flower .The above section is refered as The Human Mind. Logic here is Just Imagine u went towards a Mango tree and saw plenty of Mangoes. U start plucking it. And if Fruits are sweet and yummy then u start plucking it more and more. Wheather u thought about How this tree has grown, How long its Roots might be? How many year it took to grow itself to be the biggest tree. Never right? Well we didnt even think it takes 9 months to get this seasonal food. Until now one comes to it. To become one Tree it takes many years. Well that one fruit of a tree has to take long time to become a declicious fruit. Apart from Whole Tree we only focus on fruits i.e The Human Mind. Human Mind and fruits of a tree has only its worth if it is beautiful. As per the title i mentioned The Poison Tree! Poison is something which starts growing inside us and gradually starts spoiling. Poison here is nothing but the Hate , jealous , negative things that comes into our Mind. If a fruit of a tree is unhealthy or soar no one tries to have it. Same here if u keep hate , jealous , negative things in the mind than no one wants to crave your vibes. And if u do not deal with this kind of things at a right time then it increase like a poison. Human mind is greatest creature many things we dealth with it everyday and everytime.  Negative and positive both comes into mind but we need to focus on positive ones. Because positive thoughts are like sweet fruits which even u love to have it, where as negative thoughts are like poison which kill you from inside. The tree should not be poison if it is then tree we will cut soon. Human mind should not be filled with negative thoughts soon it will spoil .