Duplicate of this question.

I found bugs in wood that I've had air drying for the last few years. What are they?

I had a tree cut down a few years ago and some of the wood milled in to slabs. However, I've found a few pieces that appear to have bugs living in it. They seem to be some kind of larva.

The larva seem to be approximately 2cm long and maybe 1-2mm across. There have also been larger tunnels from what I assume is the adult insect that are more like 3-4 mm across. I haven't found any adult insects to get pictures of though.

Tunnels are usually packed with sawdust, but sometimes the bigger tunnels are packed with what looks more like leaves.

The picture below is of a piece of oak, but I've seen similar tunnels in some maple also.

Current searching online leads me to the Emerald Ash Borer (but it seems to only eat Ash trees?) or termites (but the larvae size doesn't seem to quite match).

I'd like to identify the insects so I can evaluate whether I can use the wood.

This is in Eastern Missouri (USA).

Image of larva

  • 3
    $\begingroup$ Welcome to Biology.SE. Please take the tour and then go through the help center pages starting with How to Ask questions effectively on this site. In particular, please note that crossposting, is considered rude — instead differentiate the questions so that they are not duplicates and are appropriate for the two sites. Also note that organism ids need more information: 1) one or more clear closeup photos (from multiple angles if possible); 2) the location (e.g. country and region); and 3) an estimate of the size. $\endgroup$
    – tyersome
    Dec 8 '21 at 1:43
  • 2
    $\begingroup$ tyersome, Thank you for the welcome. I've added the location. Unfortunately, only the one photo is immediately available. If I manage to obtain others, I will add them. The answers on the previous question directed me here. While the fundamental question (help identify the bug) remains the same, the question is not an exact duplicate. It has been tailored for this site. If further tailoring is needed, I look forward to your proposed edits. $\endgroup$
    – Elros
    Dec 8 '21 at 2:54

These are larvae of some species of wood-boring beetle. It is quite possible you've had multiple species eating your various species of wood.

  • Many species of boring insects have white, segments, worm-like larvae.

I do not know for certain what species you have, but size, phenology (e.g., timing of metamorphosis/emergence), type of wood infected, and time of infection (dead wood vs dying wood) all are helpful in narrowing down to a specific species. I recommend placing some wood with a borer in a terrarium with a screen on top and waiting to see what the adult looks like when it emerges -- and recording when it emerges.

One possibility, I suppose, is the red oak borer (Enaphalodes rufulus), though only infected specimens look like yours (though, it does appear you've only shown us the caudal side of the insect -- any head shots??).

I couldn't find evidence from a short search as to whether the invasive goldspotted oak borer (Agrilus auroguttatus) has been found in Missouri or not yet, but I will provide an image demonstrating a similar larvae morphology of this species:

enter image description here

Credit: Mike I. Jones ; Source: UCANR -- L>R: 4th instar, 4th instar in hairpin configuration, 4th instar constricted form, pupa, adult

If you could update with more info (e.g., specific species of tree) and additional photos (especially of larvae head and any emerged adults), ID to specific species would be easier.

According to forestpests.org:

Larval tunnels cause lumber cut from infested logs to be downgraded, reducing log value by up to 40% compared to top quality wood.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.