"It takes much time to kill a tree."— Why does it take much time to kill a tree? According to the poet how is the tree finally killed?

This quoted line is taken from Gieve Patal's poetry "On Killing a Tree". Here the poet is taking about the difficulties and solutions of killing a tree. He said that a tree grows slowly by consuming nutrients and water from the crust of the soil. A tree absorbs years of sunliand air through the atmosphere.  Its real strength lies in its root which is anchoring inside the earth cave. Therefore,  a simple jab of a knife and hacking and chopping can not alone kill a tree completely due to its strong healing power. A tree can rise its curled green twigs or miniature boughs from the ground.  And that is why it takes much time to kill a tree.

Amid this difficulties the poet gives a solution through which one can kill a tree easily.  As we know that a tree is anchoring its root into the earth cave. Therefore,  it is very important to pull out the root, the source and strength of the tree. After uprooting a tree, its root becomes exposed to the sunlight and air for browning,  hardening,  twisting and withering.  This is the final process that lead to the ultimate death of a tree.