Ligustrum, also known as privet, bears black berries that have caused the death of several people in Europe. All parts of the Chinaberry tree are poisonous.

Jack Berry -- Winter holly berries/ Flickr / CC BY 2.0. Holly berries contain theobromine, an alkaloid that is related to caffeine and found in chocolate.

Toxic WA plants and berries. Baneberry - Actaea rubra, Actaea pachypoda . Both red and white baneberry varieties are considered poisonous, but red baneberries are more common in Washington.