Sudden Oak Death
Phytophthora ramorum
Basic Details
Description
Taxonomy
Features
Translations
Basic Details
NameSudden Oak Death
DescriptionSudden oak death causes rapid browning and death of oaks, often marked by 'bleeding' trunk cankers. Identify foliar spots on bay laurels to detect this forest killer early.
TypeOomycete
FamilyPeronosporaceae
GenusPhytophthora
Taxonomy & Features
PhylumOomycota
ClassPeronosporea
OrderPeronosporales
Features
- A serious forest disease caused by the oomycete Phytophthora ramorum. It attacks many species of trees and shrubs, most notably oaks and tanoaks
- In susceptible oaks, it causes 'bleeding cankers'—dark, reddish-brown fluid oozing from the trunk, especially on the lower 1-2 meters
- Leaves on infected trees can turn brown and die extremely rapidly, often within 2-4 weeks, giving the disease its name 'Sudden Oak Death'
- On non-oak hosts like Rhododendron or California bay laurel, it causes foliar blight and twig dieback, which act as sources of spores for infecting oaks
- The pathogen is specialized for spread in cool, coastal climates with high rainfall and heavy fog
- Unlike many soil-borne Phytophthora species, P. ramorum produces spores on the leaves that are carried by wind-driven rain to nearby trees
- Infected trees may appear healthy until shortly before they collapse. The fungus eventually girdles the tree, cutting off all nutrient transport
- The disease has fundamentally altered forest ecosystems in the coastal regions of California and Oregon
- Manage by removing infected foliar hosts like bay laurels near high-value oak trees to reduce the local spore load
- Control using preventative phosphonate treatments applied as a trunk spray or injection to healthy or early-stage infected trees
Names in Different Languages
Latin / ScientificPhytophthora ramorum
English (Alternate)Ramorum blight
Hindiओक की अचानक मृत्यु (Oak ki achanak mrityu)
Tamilஓக் மர கருகல் (Oak mara karugal)
Teluguఓక్ చెట్ల ఆకస్మిక మరణం (Oak chetla akasmika maranam)
Malayalamഓക്ക് മരങ്ങളുടെ പെട്ടെന്നുള്ള നാശം (Ōkk maraṅṅaḷuṭe peṭṭennuḷḷa nāśaṃ)
Kannadaಓಕ್ ಮರದ ಆಕಸ್ಮಿಕ ಸಾವು ರೋಗ (Ōk marada ākasmika sāvu rōga)
Sanskritअप्लव-ओक-नाश (Aplava-oka-nāśa)
Bengaliওক গাছের হঠাৎ মৃত্যু (Oak gacher hathat mrityu)
Frenchencre du chêne
Russianвнезапная гибель дуба (vnezapnaya gibel' duba)
Spanishmuerte súbita del roble
GermanPlötzliches Eichensterben
