Ash Borer (Not Emerald)

[timbernut]

It’s very common, I’ve found they colonise felled ash as soon as the frosts end particularly if timber left on the deck for forwarding in drier weather.
Had a customer,with own small woodland that we thin and convert material to logs for him, ask me to empty his wood store full of lovely seasoned ash because he thought his house wood get infested with wood worm (it’s a 500 yr old half timbered Hall). Was about 5 tin of logs?

[timbernut]

Ton[emoji849]

[JonnyRFT]

I got a reply from the Forestry Commission for those who are interested...

 

Dear Jonathan,

 

Thank you for submitting your enquiry through Tree Alert, these are the galleries and exit holes of one of our native ash bark beetles, Hylesinus. We have a couple of Hylesinus species here, fortunately none are aggressive feeders on healthy trees – they usually require a tree to be seriously stressed or near death before they can become established. Sadly they do so there is little way back for the tree.

 

These feeding bores are typical of certain bark beetles – the two tunnels leading across the trunk are built by female beetles, whilst the tunnels running vertically are produced by the larvae as they feed, eventually exiting as adults through the bark at the end of the tunnels. 

 

When looking at galleries under ash bark our first thought is “is this emerald ash borer”, an invasive non-native species which can feed on healthy ash, swiftly killing the tree. Fortunately this species is not found in the UK, though we remain vigilant and encourage people to send us any photographs of galleries under ash bark for identification.

 

Please don’t hesitate to let me know if you have any further questions or queries.