Pest or disease?

Latin name:
Dendroctonus micans

Host trees:
Most spruce species

Present in the UK?

Tree Alert required?

The great spruce bark beetle, native to northern mainland Eurasia, was first discovered in the UK in 1982.

It's unknown how the great spruce bark beetle arrived in the UK, but its range has been increasing over the past 100 years. Great spruce bark beetle is a pest of spruce trees, spruce are not native in the UK but are widely used in forestry. In particular, Sitka and Norway spruce are widely grown for timber.

The beetle causes damage by tunnelling into the bark to lay its eggs. The hatched larvae then feed and produce tunnels in the inner living layers. This can prevent the tree transporting water and nutrients, weakening the tree and, in cases of a large infestation, can be fatal. A characteristic symptom of this pest is resin tubes which are produced when the beetle tunnels into the bark to lay eggs. Profuse resinosis, exit holes and dieback of foliage may also be seen. For more information on the great spruce bark beetle please see the resources below.