Cunningham's Encyclopedia of Magical Herbs - Scott Cunningham 1985

Roots
The Herbs

Powers: Protection, Power Divination

Magical Uses: If you must sleep outside without protection wear any root around your neck and you will be guarded from wild animals.

An old superstition has it that roots dug from a churchyard (or any old sacred site) will avert death so long as the collector wears or carries them.

According to Southern magical lore, a person planning to study magic should go to a field at night. There he or she should pull up a weed, roots and all. The amount of soil which adheres to the roots indicates the amount of power and skill the student will achieve in the magical arts. This is sometimes done by the prospective teachers, to get a glimpse of the future success of their novices.