The poet says that if we wish to kill a tree, it takes a lot of time. A simple job of the knife can’t kill a tree. A tree grows up by getting food and other nutritious from the earth. It absorbs sunlight, air, and water for years and becomes very strong. If we try to hack and chop it, it does not feel much pain. Its bleeding bark heals very soon. Small twigs begin to shoot up from it and soon they become very big and strong.
The poet says that the real strength of a tree lies in its roots. If we want to kill a tree forever, its roots should be pulled out completely. They should be left in open to withering in sun and choke in the air. Thus after a long process of changing shapes and colours, we can say that a tree is killed.
The poem “On Killing a Tree” compares the process of cutting down trees to committing an act of murder. The poet presents this view in an ironic and sarcastic tone. The pain experienced by trees while being killed dominates the mood of the poem. The poem opens with the statement that killing a tree takes a lot of time. It cannot be done merely by a stab of the knife because the tree grows up to be very strong over a period of time, gradually drawing nourishment from the earth, the sun, the air, and the water. Its bark looks dull and discoloured yet fresh leaves keep emerging from it. A tree cannot be destroyed with a few cuts and blows. The pain caused by the hacking and chopping is not enough to kill it. Its injured and mutilated bark would repair after some time and tender, green twigs will rise up from its hacked base. If these small boughs are not cut, they will soon attain the original size of the tree. According to the poet, the actual process that can kill a tree involves cruelty and ruthlessness. The root of the tree is to be pulled out from the earth which is holding it securely. It is to be ripped up by forceful pulling and snapping. This root is the true strength of the tree. It is sensitive to heat and light as it remains concealed under the surface of the earth for years. Hence, it is to be left exposed till it dries up and stops drawing nutrients from the soil for the tree. When left exposed to sun and air, the root gradually dries, withers and hardens. Life drains out of it and the tree is finally killed.