h3> Team work between Forest Research, Bangor University and others has for the first time, tracked down the cause of the stem bleeding symptoms of acute oak decline (AOD). Using the latest scientific methods they have revealed a multi-bacterial cause of the stem bleeding and pioneered novel methods for analysing the causes of complex plant […]
Field guide This document details signs and symptoms of the named tree pest(s) or disease(s) and provides advice on what to do if you suspect the pest or disease is present. Related pages Research and advice on tree pests and diseases Tree Health Diagnostic and Advisory Service Tree pest and disease posters
Pine pitch canker, also known as pitch or pitch pine canker, is a serious canker disease of pines and Douglas fir caused by the fungus Fusarium circinatum. The disease affects trees in planted forests, nurseries, parks and gardens. In plantations, the disease leads to reduced growth and cone yield and can kill trees. It will […]
Ash is a widespread species which makes a substantial contribution to many landscapes. Ash trees are affected by ash dieback, a disease caused by a fungus. It is clear from the European experience of the disease that a significant number of ash trees could be lost from woodlands in the UK over the course of […]
Study evaluating the experiences of participants of Observatree, a Tree Health Early Warning System which engages volunteers in surveying for tree pests and diseases, thereby supporting efforts to protect woodlands and forests.
Predicting future risks of damage by insect pests is an important aspect of forest management. Climate change has the potential to affect forest pests and their impact on trees through higher temperatures, altered precipitation patterns, and more frequent extreme weather events. Warmer temperatures are likely to have complex effects on insects, influencing, among other things, […]
Pine processionary moth is a serious pest of pine trees in southern Europe. The moth larvae (caterpillars) feed on pine needles and defoliate trees, which reduces tree growth and timber production. Large numbers of larvae can cause severe damage – weakening the trees sufficiently to make them vulnerable to other pests and diseases and, in […]
Chestnut blight is a serious disease of chestnut trees caused by the fungus Cryphonectria parasitica. The fungus does little damage to host trees in its native range in Asia, but has devastated American chestnut when it was accidentally introduced to the USA more than 100 years ago via infected planting stock. The disease was introduced […]
Pathology note This document details signs and symptoms of the named tree pest(s) or disease(s) and provides advice on what to do if you suspect the pest or disease is present. Related pages Research and advice on tree pests and diseases Tree Health Diagnostic and Advisory Service Tree pest and disease posters
Recent research by Forest Research scientists and colleagues at the University of York shows that northern hairy wood ants (Formica lugubris) have successfully colonised plantations of largely non-native coniferous species in the North York Moors National Park. The studies show that there has been a remarkable expansion of the population of this ant into new […]
Xylella fastidiosa is a disease-causing bacterium that affects a wide range of important woody plants and broadleaved trees. It invades the xylem vessels that transport water throughout plants, and causes symptoms ranging from leaf scorch to tree dieback and death. In the natural environment it is transmitted by xylem-fluid feeding insects such as leafhoppers. Until […]
Plane wilt, also known as canker stain disease, is a serious disorder of plane trees, which are important amenity trees in the parks and avenues of many European cities. The disease is caused by the fungus Ceratocystis platani, which is present in the USA and Europe, but considered to be indigenous only to North America. […]
UK distribution of Phytophthora ramorum evolutionary types provided by new testing method By developing a new molecular-based testing method based on PCR techniques, Forest Research scientists have been able to examine the distribution of the two main lineages of Phytophthora ramorum responsible for the major epidemic on larch (Larix spp.) in the UK. In a […]
Treating ash seeds with hot water may kill Chalara infection Immersing ash seeds in 44°C water for 5 hours may eradicate Chalara infection in ash seeds without significantly reducing the viability of the seeds. Forest Research scientists have published the results of this trial in Quarterly Journal of Forestry. Batches of ash fruits were subjected […]
News of a recent unwelcome discovery and how ‘citizen science’ can play an important role in surveying and identification. An overview of the 2015 discoveries of Dryocosmus kuriphilus (Oriental chestnut gall wasp; OCGW) in European sweet chestnut (Castanea sativa) trees in Farningham Woods, Kent and St Albans, Hertfordshire, was published in Quarterly Journal of Forestry. […]
Phytophthora austrocedri (previously spelled austrocedrae) is an aggressive, fungus-like pathogen that poses a serious threat to juniper trees in Britain. Juniper is an important native species and a significant proportion of the small area of juniper woodland in Britain is protected. Phytophthora austrocedri was first reported in the UK in 2011, and infected trees have […]
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. The causal agent of this disease is the pathogenic bacterium Pseudomonas syringae […]
Elm yellows is a disease of elm trees caused by a type of bacterium known as a phytoplasma. Symptoms of the disease can range from yellowing of leaves to dieback of foliage and branches. Elm yellows has been found affecting elm trees in North America and a few European countries, but in 2014 it was […]
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