From publisher blurb:
The Nutaberr are a rare and reclusive species. Roughly the same size as halflings, they live in treetop villages built in secluded woods far from the reach of other races. Protective of their homes, Nutaberrs will typically try to stay out of sight when confronted with intruders. Monitoring them from the branches above, they’ll attack if they perceive anything even resembling a threat to themselves or their forests.
Their isolationist lifestyle is, sadly, a learned one. Once a friendly people, the other races soured them on outside contact with a string of broken promises and betrayals. Many times in the past the Nutaberrs have seen their forests destroyed to serve the whims of others. As a result, most Nutaberrs have eschewed Common and speak only their own language. This makes communication difficult even when they are inclined to speak with interlopers.