Thistle's picture

Bark beetle?

Observed: 7th October 2012 By: ThistleThistle’s reputation in InvertebratesThistle’s reputation in InvertebratesThistle’s reputation in InvertebratesThistle’s reputation in Invertebrates
IMG_0057
Description:

Hole in the bark of a Scots Pine. Other nearby holes were round or almost round, about 2-3mm diameter. Can the culprit species be identifed from the hole?

Identifications

No identification made yet.

Species interactions

No interactions present.

Comments

DavidNotton's picture

may be same

may be same as the round ones, but looks oval because it crosses the (current) surface of the bark at an angle. When bored the hole may have been entirely inside the bark, but has been revealed by bark flaking off later.

Common inhabitants of pine trunks include the wood wasp Urocerus gigas and its parasitoids Rhyssa and Ibalia, also various beetles.

Thistle's picture

Thanks

Many thanks for this. Can you suggest what time of year I should be looking for fresh, inhabited holes?

Martin Harvey's picture

beetles in holes

The holes in bark are generally made by the adult beetles emerging from the wood, after an extended period feeding under the bark or deeper in the wood as larvae. So the adults are rarely seen at the holes unless you are lucky enough to see them at the moment of emergence.

The different species emerge at different times of year, but May is one of the peak times, when many dead-wood beetles emerge to feed as adults at the flowers of hawthorn. But you can find them at other times of year as well, and using a net to sweep around the trunks of trees is one way of trying to observe these beetles.

An alternative is to peel off bark or open up the wood itself to find the larvae or pupae before the adults emerge. This should be done sparingly though, as it inevitably damages the habitat that you are trying to investigate.

For a more detailed account of finding beetles associated with dead wood see this from the Watford Coleoptera Group:
http://www.thewcg.org.uk/pages/wood.htm

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Entomologist and biological recorder