Starting on 14 May the municipality will be injecting more than 8,500 trees to control the persistent and contagious Dutch elm disease. This happens annually to better protect the trees against the elm bark beetle.
The Hague has some 16,000 elm trees lining its streets and lanes. The municipality checks all of the elm trees each year. If an elm tree is infected, the disease can quickly spread to surrounding elm trees through the roots or the beetle itself. The elm trees are inspected twice a year between May and September. This includes elm trees known to the municipality on private properties as well.
Half of elm trees to get vaccine
Approximately half of the elm trees are getting a vaccine. The other half is represented by newer elm species which are naturally resistant to the disease and do not require the vaccine. Injecting the trees helps because only dozens of trees now die each year instead of the 1,500 to 2,000 elm trees which died from the disease about 20 years ago. The trees need to be injected early in the growing season, when the elms begin to bud. The weather also has to be good. The bark should be dry so that the tree absorbs the vaccine.
Report a sick elm tree
You can recognise a sick elm tree by its dry and withered leaves. After some time the elm tree loses all of its leaves. Have you seen a sick elm tree? Report this to the municipality on Iepenziekte melden.