The infamous modern chocolate substitute! An evergreen tree mentioned by Pliny in his Natural History for it's use in wine-making and its medicinal value, Carob(Ceratonia siliqua) is also known as St. John's bread due to legends that it is the locust on which John the Baptist dined while in the desert. A member of the Pulse or Pea family, it is native to the Mediterranean and has been a food source since prehistoric times. Carob pods are also used as livestock feed.
For those building a traditional domus in the modern world note: it is also listed by the California Division of Forestry as being fire resistant!