Sooty bark disease: tree disease dangerous for humans

1. Sooty bark blight is a rare tree disease caused by a fungus. Infection with this fungus will eventually cause the tree to die. Not only does this create the danger of branches breaking and the tree falling over, frequent contact with spores of the fungus can also lead to lung problems in humans. More specifically, there is a risk of developing the lung condition extrinsic allergic alveolitis (EAA).

Sooty bark disease

1. What is Sooty Bark Disease? Soot bark disease in the Netherlands Effects on human health Suspicion of Soot Bark Disease?

What is Sooty Bark Disease?

1. Sooty bark disease in trees is referred to when a tree is infected with the fungus Cryptostroma corticale, a bag fungus. In English, the tree disease is called sooty bark disease. Infection occurs when spores of the fungus penetrate through wounds and broken branches. Under the bark of the tree, the fungus can spread very quickly, especially in extremely hot and dry weather. Maples in particular appear to be susceptible to infection with this fungus. The first signs of infection are damage to the bark and the cambium in the form of spots and a mucus secretion. The leaves often turn white / yellow. The tree will wither rapidly in late summer, after which the crown and later the entire tree will die. Closer inspection of the tree's bark will lead to the discovery of black or black-gray spores. The tree disease owes its name to this. Examination in a laboratory can confirm the diagnosis.

Soot bark disease in the Netherlands

1. Because sooty bark blight can be dangerous for people, municipalities are extra vigilant for signs of the disease in trees. Fortunately, it is not common. The disease was diagnosed in 2014 in the municipalities of Stede Broec (North Holland) and Mill (North Brabant), in 2015 in 's-Heerenberg (Gelderland) and in 2016 in Utrecht. In 2018 the problem was again found in 's-Heerenberg. If a contamination is detected during a check, then cutting will be started immediately. Fragmentation will then not be carried out in the public space to avoid dust clouds with traces. It also happens that the disease is found in stove wood and that it is no longer possible to find out where the tree in question was.

Effects on human health

1. With frequent and prolonged exposure to the fungus Cryptostroma corticale, serious health problems can develop in humans. It concerns extrinsic allergic alveolitis (EAA), a type of inflammation in and around the alveoli caused by a late allergic reaction to inhaled organic matter. Those who suffer from the acute form of this condition have symptoms such as chest tightness, cough, fever and general malaise. In the chronic form, progressively worsening shortness of breath gradually develops and weight loss can occur.

Suspicion of Soot Bark Disease?

1. If, based on external characteristics, you suspect that a tree is infected with sooty bark disease, it is best to contact the municipality immediately. Due to the danger to public health as well as the danger of dying and falling over of the tree, a response will usually be urgent. Detection of sooty bark disease will lead to the cutting down of the tree concerned and inspection of other trees in the area.

2. If you suspect that a tree is infected with sooty bark disease on the basis of external characteristics, it is best to contact the municipality immediately. Both because of the danger to public health and the danger of dying and falling over of the tree, a response will usually be urgent. Detection of sooty bark disease will lead to the cutting down of the tree concerned and inspection of other trees in the area.