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Pests and diseases
Phytophthora lateralis
Discovered in the UK in 2010, Phytophthora lateralis is a fungus-like plant pathogen that attacks the roots of Lawson cypress trees.
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Pests and diseases
Sweet Chestnut Blight
Sweet chestnut blight is a fungus that grows beneath the bark of sweet chestnut trees causing cankers that can girdle the tree.
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Pests and diseases
Chalara Dieback of Ash
A chronic fungal disease believed to have originated in Asia, now widespread across Europe.
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Blog
Canker Stain of Plane Trees: A Silent Legacy of World War II
Canker stain of plane (caused by the fungus Ceratocystis platani) may be a rather obscure pathogen to most, but its story intertwines with one of history’s most turbulent chapters: World War II.
Duncan Allen • 29 Apr 2025
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Blog
Host of the month - Beech
Matt Parratt highlights Beech (Fagus sylvatica), its associated Beech leaf disease (BLD) and how to spot it.
Matt Parratt • 19 Jun 2025
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Host of the Month: Beech and Beech Leaf Disease - July 2025
PDF • 954 KB
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An introduction to our priority pests and diseases
Video • 00:03:36
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Tree health
The importance of biosecurity
Good biosecurity practice can reduce the risk of introducing or spreading pests, diseases and invasive species.
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Acute oak decline training video
Video • 00:08:47
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Biosecurity
Video • 00:05:55