Beetles in the Bonsai

Watch out for this beetle.  If discovered, it should be immediately reported to Plant Health and Seeds Inspectorate at 01904 465625 or

The Citrus Longhorn is an Asian beetle, accidentally imported with ornamental trees from Korea, China and Japan, and discovered at a Rutland school last week.  Like all UK sightings so far, it was found in a Japanese maple, but without a natural predator it poses a serious threat to a wide range of native shrubs and trees.

They are 2-4 cm long, shiny black with white markings and with striking antennae, ringed white and blue, as long as their bodies.

The beetle lays eggs into bark, 200 at a time, and the larvae develop out of sight for a period lasting up to 4 years, making detection very difficult.  Tell-tale signs are holes, often just above ground level, in stems and roots, as well as chewed leaves.

Recent outbreaks have been reported in France, the Netherlands and Italy, where it has become established in Lombardy.  Rapid action is necessary to avoid a difficult and costly eradication process.

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