Spooky spindle spinner

I was recently asked to call to a neighbour’s garden to see if I could identify a garden pest.

Now this is something that I often do and as I went up, I was expecting to find a plague of greenfly, or some other aphid.

What I found was something that I had never seen before. It was like a scene from Arachnaphobia or a Harry Potter movie. A tree about 5 metres high and with a spread of about 4 metres was covered in what looked like a giant spider’s web.

When I got closer I saw that it was surrounded by flying little white moths with black markings. They are quite attractive little fellas if they weren’t doing such damage to the tree. The tree is a Euonymus europeaus or Spindle Tree to give it its common name and this it’s what helped me in my search to discover what was causing the phenomenon.

The culprit was the Ermine Spindle Moth and as the name suggests it’s specific to the Euonymus europeaus. Quite common in most parts of Britain I had never seen an infestation of this moth in Ireland before.

The caterpillars create this fantastic web over the tree to protect themselves from wasps and birds as they gorge on the sap of the tree. They will weaken their host and in time cause branches to die back and eventually the tree will die if the infestation is left untreated.

There are 600 species of ermine moth and they have the potential to defoliate a tree in days Many species are only to be found in the tropics with about 75 in Britain and Ireland. In one extreme case, an avenue of trees at Jesus Green in Cambridge was covered by these webs, and in 2011 in an urban park in Bradford, 15 trees were stripped of their leaves by moths and the cause was put down to the warm weather. So maybe these moths on this Spindle tree are a symptom of the glorious month we have been enjoying. The web has been visible for the last few months as and maybe the appearance of these webs in the future may indicated a long hot summer to come.