Pest or disease?

Scientific name:
Agrilus fleischeri

Host trees:
Poplars and willows

Present in the UK?

Tree Alert required?

Agrilus fleischeri is a beetle from Asia that attacks poplar and willow trees.

It is closely related to our other priority pests Bronze birch borer and Emerald ash borer, and to the Oak jewel beetle which is closely associated with Acute oak decline. It is native to Asia and is known to be present in China, Japan, Kazakhstan, Mongolia, North Korea, South Korea and Russia.

Like its relatives A. fleischeri is a wood borer, the larvae cause destruction by feeding and tunnelling under the bark of the tree. Whilst generally not fatal to the host it is thought that the beetles can reduce their productivity and vitality and make them more vulnerable to other pests and diseases. Fatal infestations have however been reported in Lombardy poplar (Populus nigra var. italica) in China but the species also affects several other poplar species and narrow-leaf willow (Salix schwerinii).

The non-native but closely related A. ater has recently been found breeding in the UK and is physically very similar to A. fleischeri. The larvae of both are found in poplar trees but A. ater seems to prefer stressed or dying trees whereas A. fleischeri appears to be more aggressive and can also attack healthy trees.

Signs to look out for include D-shaped exit holes in the bark, like other agrilus species. Infestation is likely to be difficult to detect until the symptoms become severe because much of the insect’s life cycle is hidden within the tree. For more information on this pest please see the resources below.