Horse Chestnut canker in the Sid Valley

Trees are important in many many ways:
Futures Forum: The urban tree canopy
Futures Forum: Trees reduce pollution

Several are under stress, though:
Futures Forum: The Yew, the Sycamore and the Ash

Horse Chestnut canker is now widespread throughout most of England - as reported by the Forestry Commission recently:

Horse chestnut is an important amenity tree species which has been significantly affected over the past decade by a widespread outbreak of bleeding canker disease. Symptoms include rust-coloured or blackened bleeding cankers on the stem and branches, which can lead to tree mortality. 

Horse chestnut bleeding canker - forestry.gov.uk

Indeed, its prevalence is estimated to be about 50% in the South West.

Horse chestnut bleeding canker - Pests & Diseases

Extent of the bleeding canker of horse chestnut problem (Forest Research)

The Sidmouth Arboretum's Ed Dolphin writes about the disease in the Sid Valley:

Sad to report but one of the magnificent horse chestnuts in Knowle park looks very sick and there is evidence of a black weep from cracks in the bark.

Pictures attached:

And close up of the diseased tree:

Compared with its healthy neighbour:

Sidmouth Arboretum
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