Xylella fastidiosa

Pierce's disease

Photo: Alex H Purcell, University of California, Berkeley, Bugwood.org

  • A bacterium that lives in the water conducting system (xylem) of plants
  • Grapevines show symptoms of water stress, such as leaf scorch, and the plant progressively weakens and dies
  • Can be transmitted in infected propagation material and by leafhoppers such as the exotic glassy-winged sharpshooter
  • Present in North America, Central America and some regions of South America. It is present in a restricted range in Italy, Iran and Taiwan, and is under eradication in some other countries in Europe. View a distribution map.
  • The diseases caused by Xylella fastidiosa go by a range of names depending on the host species, including: Pierce‚Äôs disease, almond leaf scorch, bacterial leaf scorch, citrus variegated chlorosis, olive quick decline and olive leaf scorch.

Other information


High priority pest of: Almonds, Berries, Blueberries, Cherries, Citrus, Coffee, Macadamias, Nursery and Garden, Olives, Pecans, Summerfruit (& canned fruit), Viticulture (dried, table and wine grapes)

Scientific name: Xylella fastidiosa including X. fastidiosa subsp. multiplex and pauca
EPPRD Category: 2
Life Form: Bacteria

Pest Documents

FS: fact sheet

CP: contingency plan

DP: diagnostic protocol