"In Paul Friedrich's book Proto-Indo-European Trees he identifies the "semantic primitives" of the Indo-European tribe of languages through a group of words that have not changed much through twelve thousand years - and those are tree names: especially birch, willow, adler, elm, ash, apple and beech (bher, wyt, alysos, ulmo, os, abul, bhago). Seed syllables, bija, of the life of the west."