Eihwaz represents the vertical axis. It is also indicative of the verticality and energy of the human spine and represents the communication between levels of reality. The needle of the yew is poisonous, containing a toxin that affects the central nervous system. The vapors from the toxin can become concentrated in close proximity to the tree. As a conifer, it is associated with immortality, and the mysteries of life and death. Death is understood as the Great Initiation into the mysteries of life. To die before you die is to discover what in life is truly important.