Sudden Oak Death Outbreak
Tuesday, September 28th, 2010Unfortunately Phytophthora ramorum is once again occurring. Also know as Sudden Oak Death, cases have been reported in Cornwall, Staffordshire and in Devon. This disease affects the Rhododendron species, but can also be found on Pieris, Leucothoe, Viburnum and Larix. Inspectors from FERA the Food and Environment Research Agency have confirmed these outbreaks.
It was first identified in California in 2000 and then later in Oregon, USA. However, the form of P. ramorum in North America is of a different sexual mating type to the fungus in Europe.
Infection by P. ramorum is usually characterised by the presence of dark red to black sap oozing from the trunk: bleeding cankers or tarry spots. This is often on the lower portion of the trunk but may also occur several metres up the stem. When the outer bark is removed from the bleeding canker, mottled areas of necrotic, dead and discoloured dinner-bark tissue can be seen. Black zonelines are often present within and around the edges of the necrotic region.
Frankly, I am glad not to be a Shrub or Tree.
Defra has recognised the value of trees in controlling climate change in it’s recently published Climate Change Plan 2010.
