Forestry is one of the core Ranger skills and deals with the manipulation of the forests and the skills of the wilderness. It has myriad abilities, beginning with simple improvisation and woodland skills for the young, through archery and travel through the treetops. Legend states that the greatest rangers can even assume the Form of the Bear and carve symbols of mythical origin into the very trees to spread their power about the land.
This is also a skill learned temporarily, to a low level, by scholars. Sample well its fruits.