DEFRA has found the pathogenic fungus Cryphonectria parasitica in Sweet Chestnut Trees in Devon. Oak trees can get infected but they only suffer superficial damage (we hope) although they can spread the disease.
This is the same disease that arrived in America in 1904 on imported plants from Japan. In 40 years the disease had killed 5 billion American Chestnuts and the tree is now classed as 'technically extinct'.
The hyphae of the fungus produce toxic compounds, including Oxalic Acid. This lowers the PH of the affected tissue from normal 5.5 to 2.8 which is toxic to plant cells.
There are good populations of Sweet Chestnut - Castanea sativa in England, and many centuries old trees in the North of England. Below is a photo of 3 of them at Levens Park, near the Lake District.
Let's hope the containment notices stop the spread of this disease.
Sweet Chestnut Trees
Another worrying disease.
ReplyDeleteI only know small suckering Sweet Chestnuts in our area.
There was an old Sweet Chestnut in Well Head Fields near the Shay Football ground which we lobbied to retain, along with the fields around it, but they got houses built on them, and the tree destroyed.
It had a spiral pattern to its bark-grooves around the trunk.
I was thinking about the Elms in connection with Lesser Spotted Woodpeckers. Both have become rare. Maybe there was a relationship. The only nest I ever saw was in the dead trunk of an Elm at Elland.
Thanks for your fascinating posts, Philip.
ReplyDeleteHope you don't mind that I've put our poster back up to the top.
Hi Steve, It's me that should be thanking you and the HSS for allowing my postings on your blog! Hope you find some of interest.
ReplyDeleteAbout local Sweet Chestnuts. There is one in Centre Vale Park at Todmorden that is maybe 170 years old. Also a coppiced one in the Park woodlands planted about 30 years ago.
There was a large one in Hebden Bridge that had a TPO but was legally felled a few years ago.
As you have observed Steve, older trunks have a characteristic spiral pattern on the trunk.