Ceratonia siliqua
Common name: 
St. John's Bread
Locust Bean
ce-(or ke)-ra-TO-nea si-LEK
Native to (or naturalized in) Oregon: 
  • Broadleaf evergreen tree or large shrub to about 30-40 ft (10-12 m) tall, broad semispherical crown and a thick trunk, often multistemmed, with brown rough bark and sturdy branches.  Leaves alternate, pinnately compound, 10-20 cm long, 3-7 leaflets, may or may not have a terminal leaflet, leaflets are 3-7 cm long, ovate to elliptic, normally 4-10 opposite pairs, dark green and shiny above, pale green below and finely veined with margins slightly undulate, and tiny stipules.  Flowers are usually dioecious - male and female, but sometimes perfect (having both male and female parts), they are green-tinted red, small and numerous, 6-12 mm long, spirally arranged along the inflorescence axis in catkin-like racemes, 2-6 cm long, borne on spurs from old wood and even on the trunk.  Fruit is an indehiscent pod, elongated, compressed, straight or curved, thickened at the sutures, 10-30 cm long, 1.5-3.5 cm wide, brown with a wrinkled surface and leathery when ripe in fall.
  • Sun;  drought tolerant, needs only infrequent deep watering, additional water needed to produce quality pods.  Will retain its lower branches and thus can be grown as a large hedge.
  • Hardy to USDA Zone 9 (Thrives in regions where citrus grow well.)    Native to the Mediterranean region, where many cultivars have been selected for commercial production.  Spanish missionaries introduced the carob into Mexico and southern California, in addition to its commercial use, it has also been used as ornamental and street trees.  Carob has since escaped from cultivation and naturalized in parts of California, Arizona, Florida and Texas; it is considered an invasive weed in parts of Southern California.
  • The term carat (or karat), the weight unit to measure gold, diamonds, other gems and pearls, is derived from the Greek word keration, alluding to an ancient practice of people in the Middle East weighing gold and gemstones against the seeds of the carob tree.  Later the system was standardized and one carat was fixed at 200 milligrams.
  • When John the Baptist was in the Wilderness some think he ate the pods of the Locust Bean or Carob, hence one of its common names is St. John's Bread.   The pods are rich in sugar and are milled as a chocolate substitute, they contains less fat and more vitamins than cocoa, and are sold as cocoa substitute in health stores.  The hard seeds inside the pods are not edible.  Pods are used as livestock feed in southern Europe, especially for horses.
  • For more information see the monograph published by the International Plant Genetic Resource Institute, http://www.bioversityinternational.org/publications/Pdf/347.pdf
  • silique: Latin, alluding to the shape of the pod
Click image to enlarge
  • plant habit

    plant habit

  • plant habit

    plant habit

  • branches


  • leaves


  • leaf


  • trunk, bark

    trunk, bark