“Ethnobotany is defined as the study of the relationship between people and plants and most commonly refers to the study of indigenous uses of plants. In other words, it is the marriage between cultural anthropology and botany, a study that investigates the roles of plants as medicine, nurishment, natural resources or gateways to the gods.”
http://www.sacredearth.com/ethnobotany/ethnobotanyportal.php
“Since time immemorial plants have played a key role in human spirituality. Their sublime beauty, entrancing scents and sometimes their intoxicating fruits have always suggested a connection with 'the other world', the non - material world of Gods and spirits, demons and devils.”
http://www.sacredearth.com/ethnobotany/sacred/Sacred.php
“Ancient cosmologies tell of a magnificent World-Tree that grows at the centre of the universe and encompasses all realms of existence: its stem pierces through the world of human affairs, its branches reach high up to the domain of the Gods, upholding the firmament of the heavens and all the stars and planets, while its roots stretch far down into the dark, chthonic Underworld, forming a gateway to the realm of the dead. The image of the World-Tree or Tree of Life is truly universal. It can be found at the centre of archaic cosmological iconography in widely separated cultures all over the world.”