1- In olden times the mandrake root was taken to symbolise man. It was often used in magical ceremonies, and thus became significant in the same way that a voodoo doll can be significant. When the mandrake root or a manikin is recognised in a dream, we are linking in with our own wish to harm other people and with our conflict with someone else. Interestingly enough, the mandrake root is also a symbol of the Great Mother (see Introduction), and therefore represents feminine aspects. So, in witchcraft, the witch was in fact linking with the destructive powers of her own Self.
2- The significance of mandrake within a dream is that perhaps of word association. We are not necessarily dreaming of the root itself, but are trying to make sense of some aspect of the personality around us that appears not to be fully formed in some way.
3- The power of life and death in spiritual terms is our right to exist in a way that is commensurate with our own beliefs.... Ten Thousand Dream Dictionary