> The Elder Mother is thought to be the guardian of the elder trees, a
Must be something with old Indo-European roots (or even older than that), because we have something very similar in Romanian folklore, it's called Muma Pădurii (literally translated as Forrest Mother). From wikipedia [1] (very rough translation by me):
> Muma Pădurii is a Romanian mythology character which is often present in Romanian fairy-tales. According to Romanian folk tradition she is an ugly witch, who lives alone, deep in the forrest and she scares people. It looks like she is also present in the Slav folk-tales under the name of Baba Yaga
As that wiki quote says, the Slavic people have something similar under the name of Baba Yaga [2]