Sudden oak death is the common name of a disease caused by the oomycete plant pathogen Phytophthora ramorum. The disease kills oak and other species of tree and has had devastating effects on the oak populations in California and Oregon as well as also being present in Europe. Symptoms include bleeding cankers on the tree's trunk and dieback of the foliage, in many cases eventually leading to the death of the tree.
P. ramorum also infects a great number of other plant species, significantly woody ornamentals such as Rhododendron, Viburnum, and Pieris, causing foliar symptoms known as ramorum dieback or ramorum blight. Such plants can act as a source of inoculum for new infections, with the pathogen producing spores that can be transmitted by rainsplash and rainwater.
P. ramorum was first reported in 1995, and the origins of the pathogen are still unclear but most evidence suggests it was repeatedly introduced as an exotic species. Very few control mechanisms exist for the disease, and they rely upon early detection and proper disposal of infected plant material.
Read more about Sudden Oak Death: Presence, Hosts and Symptoms, Transmission, The Two Mating Types, Possible Origins, Ecological Impacts, Government Agency Involvement
Famous quotes containing the words sudden, oak and/or death:
“A circle swoop, and a quick parabola under the bridge arches
Where light pushes through;
A sudden turning upon itself of a thing in the air.
A dip to the water.”
—D.H. (David Herbert)
“Below me trees unnumbered rise,
Beautiful in various dyes:
The gloomy pine, the poplar blue,
The yellow beech, the sable yew,
The slender fir that taper grows,
The sturdy oak with broad-spread boughs.”
—John Dyer (1699–1758)
“I’m beginning to believe that Killer Illiteracy ought to rank near heart disease and cancer as one of the leading causes of death among Americans. What you don’t know can indeed hurt you, and so those who can neither read nor write lead miserable lives, like Richard Wright’s character, Bigger Thomas, born dead with no past or future.”
—Ishmael Reed (b. 1938)